Monday, December 31, 2007

ProMED Internet-a-thon

Today is the last day to contribute to the ProMED-mail Internet-A-Thon.

Your financial support enables ProMED to continue providing you and 42,000 others in 170 countries worldwide with reliable, independent reporting of emerging infectious diseases and outbreaks as they happen.

Wednesday, December 26, 2007

Contagious Yawning

Via Gene Expression: Biology Letters reports "the disturbance of contagious yawning in individuals with autism spectrum disorder (ASD)."

Yawning video clips elicited more yawns in TD [typically developing] children than in children with ASD, but the frequency of yawns did not differ between groups when they observed control video clips. Moreover, TD children yawned more during or after the yawn video clips than the control video clips, but the type of video clips did not affect the amount of yawning in children with ASD. Current results suggest that contagious yawning is impaired in ASD, which may relate to their impairment in empathy. It supports the claim that contagious yawning is based on the capacity for empathy.


The news has already made it into the Wikipedia section on contagious yawning.

Monday, December 24, 2007

Christmas Clusters

PlagueBlog apologizes for falling behind in bird flu reporting. The clusters were coming fast and furious last week, but without sustained transmission. Armageddon is postponed once again. Here's a cluster roundup, mostly via ProMED-mail, as usual:

The WHO washes its hands of the cluster question in China:

The World Health Organization said Friday it was impossible to say whether a case of bird flu in China involving a 52- year-old man was due to human-to-human transmission - but, even if it was, it was down to very close contact between the victims.


The Indonesian cluster has dissolved, at least in the opinion of the Indonesian government, that bastion of bird-flu responsiveness:

Two sets of laboratory tests showed the six admitted to a hospital in Jakarta on Friday did not have the H5N1 virus, said Nyoman Kandun, director-general of communicable disease control at Indonesia's health ministry.


Pakistan is double-checking the WHO's negative results for their erstwhile bird flu cluster:

"In their preliminary tests the WHO team excluded suspected human-to-human transmission, but we have sent the samples to Geneva for further confirmation," health ministry spokesman Oriya Maqbool Jan told AFP.

The WHO team was sent after the ministry announced the death of a man who was one of six people infected with the deadly H5N1 strain of the avian influenza virus in North West Frontier Province along the Afghanistan border.

A brother of the victim also died before being tested for the virus. Both had worked on a cull of infected poultry.


PlagueBlog finds it suspicious that the "first" bird flu case in Pakistan was a cluster of six, and also that the first report out of China in six months was a cluster of two.

Thursday, December 13, 2007

Epilepsy Drugs and Asians

Via the About.com Rare Diseases Blog: the FDA has recommended that persons of Asian ancestry have a genetic test for the HLA-B*1502 gene before taking epilepsy drugs containing carbamazepine, because of the risk of rare skin reactions. Gory pictures are available in this PDF about SJS.

Wednesday, December 12, 2007

Boy Meets Bat

Via Universal Hub: boy meets bat in basement and may yet live to tell about it.

Please remember that bats are not our friends. Bats are blood-sucking, disease-bearing flying rats out of a Cthulhu Christmas Special where the lucky ones die early and the handsome brave ones die pathetically later, foaming at the mouth and biting their friends in order to spread the madness. Just keep away. If you happen to come into contact with a slow-moving bat, save it for testing and see a doctor. Likewise for squirrels.

Up to a hundred people die of rabies every day in Asia because they don't know enough to seek treatment. Here in civilization, bats are the up-and-coming culprit:

Recently, bat rabies has emerged as an important epidemiologic reservoir in some parts of the world (i.e. the Americas and Australia). In North America, most documented human rabies deaths occurred as a result of infection from the silver haired bat rabies virus variant and in Australia at least two human deaths have occurred from exposure to a previously unrecognized rabies virus. In South America, wildlife rabies, especially bat rabies is increasing. For the first time in 2003, more people died from rabies following bites from wildlife than from dogs in South America.

Sunday, December 02, 2007

New Strain of Ebola

The Atlanta Journal Constitution, your source for up-to-the-minute CDC news, reports that the current Ebola outbreak in Uganda (51 cases and 16 deaths as of Wednesday, according to the WHO) is due to a new, fifth strain of the virus:

Samples arrived at CDC's Biosafety Level 4 labs in Atlanta on Monday. By Tuesday, Ksiazek said, it was apparent this was not a typical Ebola virus.
Dr. Stuart Nichol, a CDC special pathogens team leader, said some molecular tests for Ebola were coming back negative, when another type of test came back positive. The CDC lab was then able to extract a small fragment of the virus' genome.
"It looks, based on this, like it's a new species of Ebola," Nichol said Friday evening.
Previously, there were only four known types of Ebola. The Sudan and Zaire species were discovered in 1976. A strain called Reston was identified in 1989 among monkeys imported to a lab in Virginia. And in 1994, the Ivory Coast strain was identified.
Depending on the strain, the death rate varies. Ebola-Zaire kills about 80 percent of its victims, while the Sudan strain kills about 50 percent, Ksiazek said.

Thursday, November 29, 2007

Hope for the Tree Man

Via Daring Fireball: the UK Telegraph reports some hope for the Indonesian tree man:

"The likelihood of having his deficiency is less than one in a million," Dr Gaspari told the Telegraph.
Dr Gaspari, who became involved in the case through a Discovery Channel documentary, believes that Dede's condition can be largely cleared up by a daily doses of a synthetic form of Vitamin A, which has been shown to arrest the growth of warts in severe cases of HPV.
"He won't have a perfectly normal body but the warts should reduce in size to the point where he could use his hands," Dr Gaspari said.
"Over the course of three to six months the warts should be come smaller and fewer in number. He will be living a more normal life."
The most resilient warts could then be frozen off and the growths on his hands and feet surgically removed.

Thursday, November 08, 2007

Zombie Protest at City Hall

I was lucky to see the latest zombie protest at Boston City Hall on my way home from work last night. Personally, I'd think zombies would be happy to have snackable Ebola victims lurching about the city leaking sauce, but perhaps that's the point. I didn't want to stick around for the explanation via bullhorn, so I read it today in the BU Daily Free Press:

With Boston Police Department officers close behind, the horde of protesters began their menacing march at the corner of Albany and East Dedham Streets and snaked toward City Hall, moaning, "We have been infected by the BU biolab" and "The BU biolab has infected me with a terrible pathogen." During the march - the newest form of protest in a seemingly futile battle to stop construction of the biolab - the zombies stuffed anti-lab flyers under the doors of nearby businesses and into the palms of curious onlookers.
Local activists have protested the biolab, under construction at the BU Medical Campus in the South End, since the National Institutes of Health granted BU $128 million for the project in 2003. The site will house some of the world's deadliest pathogens, including anthrax and the Ebola virus.

Wednesday, November 07, 2007

Parasitic Twin Removed

Via Boston NOW: a team of thirty doctors at the Sparsh Hospital in Bangalore successfully removed a four-limbed parasitic twin from two-year-old Lakshmi Tatma. ABC News has more:

The surgery removed the extra body parts and unfused Lakshmi's spine from her twin's. To rebuild her pelvis, surgeons used tissue from the twin. And to save her kidney, doctors said, they had to remove it from the "parasitic abdomen" and move it into Lakshmi's own abdomen. She may still need more surgeries.

Wednesday, October 31, 2007

Wednesday, October 24, 2007

Salmonella Sushi

Via Universal Hub: Wicked Local Brookline reports on salmonella and vermin at Fugakyu:

Inspectors visited Fugakyu in late August after the Boston Department of Public Health told the town that one of the restaurant’s employees had contracted salmonella poisoning.
The restaurant, at 1280 Beacon St., reportedly had not told Brookline officials about the potential health danger. It was not clear from reports how Boston found out. [...]
Reports stated food handlers were also seen washing their hands with no soap for only five seconds. The worker with salmonella was allegedly handling food at the time of the visit, according to reports.


Let's hope Dice-K keeps away from his eponymous roll until the World Series is over.

Sunday, October 14, 2007

Adenovirus on the Rise

Via ProMED-mail: Reuters reports on a rise in the prevalence and severity of adenovirus infection (one of several causes of the common cold).

Gray's team used the test on 2,200 samples from 22 U.S. medical facilities, including eight military sites. Military personnel are especially susceptible to outbreaks of all kinds of disease, including adenoviruses.
Adenovirus 21 was found in 1 percent of specimens in 2004, but in 2.4 percent in 2006. And it was making people much sicker than the other strains, killing 50 percent of bone marrow transplant patients, for instance.

Saturday, October 06, 2007

Salmonella in Strange Places

Via an unnamed source: CBS reports on a recall of white chocolate.

Kraft Foods announced Thursday it is recalling white chocolate distributed in the United States because of possible salmonella contamination.
Kraft said consumers who purchased its six-ounce, Baker's Premium White Chocolate Baking Squares should immediately discard the product. The recalled product was distributed nationally and have the UPC Code 0043000252200 and best when used by dates of March 31, April 1, April 2 and April 3, 2008.
The U.S. Food and Drug Administration detected the presence of salmonella in some packages of the white chocolate baking squares during tests, according to Kraft.

Tuesday, September 25, 2007

Salmonella in Space

Via GeekPress, among others: The AP reports on the B-movie salmonella that came back deadlier after its trip on the space shuttle:

After 25 days, 40 percent of the mice given the Earth-bound salmonella were still alive, compared with just 10 percent of those dosed with the germs from space. And the researchers found it took about one-third as much of the space germs to kill half the mice, compared with the germs that had been on Earth.
The researchers found 167 genes had changed in the salmonella that went to space.
Why?
"That's the 64 million dollar question," Nickerson said. "We do not know with 100 percent certainty what the mechanism is of space flight that's inducing these changes."
However, they think it's a force called fluid shear.

"Being cultured in microgravity means the force of the liquid passing over the cells is low." The cells "are responding not to microgravity, but indirectly to microgravity in the low fluid shear effects."

Monday, September 24, 2007

Toxoplasmosis and You

Today's featured parasite is the stealthy and adaptable protozoan, Toxoplasma gondii.

This is the cat-litter bug that causes miscarriages and birth defects. The cat-loving parasite that lures rats to their deaths and causes traffic accidents. The latest schizophrenia suspect and a possible cause of epilepsy, psychosis, and migraines.

T. gondii may be making society rigid and neurotic, men more masculine, stupider, or more surly, and women more promiscuous. And if you think things are bad in the northern hemisphere, you should see the Brazilian strains.

About 16% 11% 33% of Americans are infected; infection rates are much higher in tropical countries (and France). Wikipedia tells the sad tale of Louis Wain, English cat artist, late-onset schizophrenic, and poster-child for the toxoplasmosis-schizophrenia connection.

T. gondii has its own book, conference, mugs and a blog, The Anti-Toxo, where you can follow mankind's losing battle with our one-celled masters.

Image by kqedquest. Some rights reserved.

Sunday, September 23, 2007

Ebola in the Congo

Via ProMED-mail: USA Today reports a total of nine confirmed cases of Ebola in the Democratic Republic of the Congo.

At least 167 people have died — though it is not clear how many of Ebola — in the affected region of Kasai Occidental over the past four months, and nearly 400 have fallen ill, according to Congolese health officials.
Christiana Salvi, a spokeswoman for the World Health Organization effort in Congo, said that the newest cases came from the same zone as the original confirmed samples.
She added that some of the 40-odd samples sent for testing have been negative for Ebola, but positive for other diseases like shigella — a diarrhea-like disease — or typhoid. Results from dozens more samples have yet to be released.

Friday, September 21, 2007

Bat Woman Found on Facebook

ProMED-mail reports that the mysterious woman who brought a rabid bat to the Toronto Wildlife Center has been found and inoculated:

Toronto Public Health has located the woman who had delivered an injured bat to the Toronto Wildlife Centre that later tested positive for rabies. Finding her proved to be very challenging as the Wildlife Centre did not have her updated demographic information. After several attempts to locate her, including a media release, proved to be unsuccessful, one of the communications staff at Toronto Public Health suggested using the website "Facebook.com".


If you come across an injured rodent of a populous and frequently rabid species, Plagueblog recommends that you walk away and let Darwin handle the situation.

Monday, September 17, 2007

Schizotypal Selection

Via John Hawks and the Four Stone Hearth Carnival of Anthropology: The Primate Diaries' explains Sapolsky's theory of selection for schizotypal personalities, possibly in shamans.

Several years ago Robert Sapolsky suggested that genes promoting schizophrenia may have been selected for in human evolution because some of them conferred benefits that outweighed the 1% of people worldwide that were disabled by the disorder. Like the sickle-cell trait that confers resistance to malaria (so long as you don’t receive two recessive alleles and develop full fledged sickle cell anemia) a partial schizophrenia may be beneficial in some way. He observed that relatives of schizophrenics have a high likelihood of “schizotypal personalities,” or a mild form of the disorder that just makes these people a little strange and allows them to see the world in a unique way. What if, he wondered, schizophrenia maintained itself in human populations because of selection for schizotypal personalites? As luck would have it, for a hundred years anthropologists had observed such individuals thriving in nearly every society they encountered: shamans.

Sunday, September 16, 2007

Leishmaniasis endemic in North Texas

Via ProMED-mail: UT Southwestern reports that Leishmania mexicana should be considered endemic in North as well as South Texas.

North Texas doctors must have a high index of suspicion and understand that this organism must now be considered endemic in this area, said Dr. Kent Aftergut, a clinical instructor of dermatology at UT Southwestern and in private practice at Methodist Charlton Medical Center.
“Luckily, all of the leishmaniasis cases in North Texas that have been cultured have grown Leishmania mexicana, which is less dangerous than other forms of the parasite,” he said. “It makes skin sores, but the infection doesn’t spread and become a full body disease like some of the others species of Leishmania. Usually, if patients have a normal immune system, the sores will resolve in six to 12 months and won’t make the patients ill.”

Monday, September 10, 2007

Bird Flu Hits 200

Via ProMED-mail: AFP reports Indonesia's 85th bird flu fatality, for a total of 200 bird flu deaths worldwide.

The plantation worker died at 2:00 pm (0700 GMT), the doctor treating him at the state general hospital in the city of Pekanbaru, Azizman Daad, told AFP.
A health ministry official earlier confirmed that the man was infected with the deadly H5N1 virus, after two tests came back positive.
H5N1 is endemic in birds across nearly all of Indonesia.
The archipelago nation has now reported 106 cases overall, including the 85 deaths.
Daad said it was not clear whether the man had come into contact with infected poultry, but he had bought two live chickens at a local market.

Wednesday, August 29, 2007

Rock Snot in New England

Via Universal Hub: The Huffington Post reports on the dangerous advance of Didymosphenia geminata, or rock snot, into New England.

"We're starting to realize it's all over the place," said Karl Hermann, a regional waste monitoring and assessment coordinator for the Environmental Protection Agency in Denver.
What started out in Vancouver Island in British Columbia "has suddenly just skyrocketed," he said.
The algae has the potential to bloom into thick masses with long stalks, blanketing the bottoms of some streams, threatening aquatic insect and fish populations by smothering food sources.
In New England, it has turned up in the White River, Connecticut River and the Batten Kill, a trout fishing mecca in southern Vermont that's famed for its hard-to-catch fish. Quebec is grappling with it in Matapedia River in the lower St. Lawrence.
There's no easy way to get rid of it. Experts say the only hope is to keep it from spreading. But that's a lofty challenge, since a single cell carried on absorbent fishing gear or clothing can be transferred _ unknowingly _ into other waters.

Monday, August 27, 2007

Dopamine Agonies

Google Alerts brought me a very odd story from the Kenilworth Weekly News, in which a masked Parkinson's sufferer accosted a British schoolgirl in her home. But it became somewhat less odd when USA Today reported on the weird obsessions of patients taking too much dopamine agonist:

They still don't have hard-and-fast proof, but as the evidence accumulates, many scientists now say the drugs can kick off compulsive urges in certain people.
And they say the side effect is anything but rare.
At a meeting in Toronto last month, Stacy and other experts reviewed the cases reported so far and concluded that the drugs appear to trigger a syndrome of bad behavior that includes compulsive gambling, shopping, binge eating and an unstoppable urge for sex.
"Fifteen percent of all Parkinson's patients might have this syndrome," Stacy says. If he's right, that could mean as many as 150,000 people in the USA are struggling with out-of-control behavior. Even those numbers may underestimate the problem.


The judge refused to jail the unfortunate patient, and the defense attorney gave a rare but unsurprising glimpse into the NHS:

"He finds everyday life very difficult. He can speak but with an almost uncontrollable stammer at times. Even a month in prison in his condition would be inhumane."
Mr Ward added that Guest, who has the support of his family, needs help, and has an appointment with a doctor at the Queen Elizabeth hospital in Birmingham later in the year.

Thursday, August 23, 2007

Good Filoviruses Make Good Neighbors

Via Universal Hub: the Boston Globe reports on the NIH's Draft Supplementary Risk Assessments And Site Suitability Analyses for the National Emerging Infectious Diseases Laboratory Boston University. In short, there's no reason Boston University shouldn't build a new lab in the South End to play with Ebola:

Researchers at the State University of New York at Buffalo compared what would happen if germs migrated from the lab into its South End neighborhood with what might happen if the lab had instead been built on more secluded property owned by BU in Tyngsborough or Peterborough, N.H.
The report concludes that even if an accident happened in the lab "under realistic conditions, infectious diseases would not occur in the communities as a result." The study also concludes that "there was no difference in simulated disease transmission among the urban, suburban, or rural communities."

Thursday, August 09, 2007

TB at the OCME

Via an unnamed source: The Boston Herald reports that state health officials will give a press conference later today about a tuberculosis outbreak at the Office of the Chief Medical Examiner.

The sources differed on whether the testing was routine or the result of a recent positive case within the troubled office.
Regardless, the two sources confirmed that at least three employees of the OCME tested positive. At least one employee has been prescribed a nine-month regimen of medication to treat the symptoms and will also undergo monthly liver testing.
“They are trying to test as many people as possible,” said one source. “People are back working. As far as I know they are not walking around wearing face masks. I dont know where they got it. They probably got it from the building.”
Another source, who is familiar with law enforcement issues, said that one or two medical examiners and at least three clerical workers were affected to some degree by the TB outbreak. The office employs about 60 people.
Dr. Joseph Prahlow, president of the National Association of Medical Examiners, said TB was known to affect medical examiners’ offices. “It’s a recognized potential hazard of the work that we do,” he said.

Wednesday, August 01, 2007

Nature Finds a Way

Eye on DNA reports on a mule who gave birth to a...mulette?

If a horse breeds with a donkey, they end up with sterile offspring that have 63 chrosomes - 32 chromsomes from the horse parent and 31 from from the donkey parent. Horse-donkey offspring aka mules are sterile because their odd number of chromosomes makes it technically difficult for chromosomes to pair up properly during the process of meiosis (cell divison of sperm and eggs). This should mean that mules cannot reproduce.
A female mule in Colorado has beaten insurmountable odds and given birth to a foal.

Thursday, July 19, 2007

Harry Potter and the Incomplete Penetrance

Via Eye on DNA: Pondering Pikaia gives an overview of controversial theories on the genetics of wizardry.

First up: the genetics of wizardry. What makes a person a wizard, and not a muggle? There was actually some discussion in the journal Nature on this very topic, back in 2005: a letter (Craig, J. Dow, R. and Aitken, M. Harry Potter and the Recessive Allele. Nature. Vol 436: 776.) and a rebuttal letter (Dodd, A., Hotta, C. and Gardner, M. Harry Potter and the Prisoner of Presumptions. Nature. Vol 437, p 318.).
The first letter claims that being being magical must depend upon a recessive allele. Wizards can have a variety of family histories: they can be born from a purely magical family, they can come from a strictly nonmagical family, or they can have one magical and one nonmagical parent (commonly scorned as "mudbloods" by haughty purebloods such as the Malfoys). Since wizards/witches can be born into muggle (nonmagical) families, Craig et al suggest that magical ability is a recessive trait (they designate the wizard allele as W and the muggle allele as M). They hypothesize that all wizards/witches are WW, which can result from a cross between two muggle "carriers" that are MW.

Tuesday, July 17, 2007

Smallpox and the Little Ice Age

Via Analog Science Fiction and Fact: Richard A. Lovett's column on "The Ice Age That Wasn't" in the April issue was partly drawn from Plows, Plagues, and Petroleum by William F. Ruddiman. An Amazon reviewer explains Ruddiman's smallpox connection:

He proposes that major plague pandemics have caused sufficient die-offs, abandonment of farms, and reforestation to temporarily lower CO2 and temperature. This could explain the later-Roman/Dark Ages lower temperatures, followed by the relatively disease-free Medieval Warming Period, in which Greenland was settled, and UK vineyards spread again to current levels, if not quite as far as early Roman. He ascribes the Little Ice Age drop to Bubonic plagues in Europe, and especially, to the death of estimated 50 million native Americans from smallpox and other European diseases.

Monday, July 16, 2007

Wolbachia and the Single Butterfly

Via John Hawks: MSNBC reports on a butterfly population that has developed resistance to the bacterial parasite Wolbachia.

Sylvain Charlat of the University of California, Berkeley, and the University College London, along with colleagues, studied the sex ratios of Hypolimnas bolina butterflies on the Samoan islands of Upolu and Savaii, where males had dwindled to 1 percent of the populations in 2001.
The likely culprit was a male-killing parasite, Wolbachia, which lives inside the butterfly’s reproductive cells, preferably female sex cells. With a female host, Wolbachia can hitch a ride to the next generation aboard the mother’s eggs. Since males are “useless” for the bacteria's survival, the parasite kills male embryos.
But the male butterflies found a way to stealthily overcome the parasites. At the beginning of 2006, the scientists found the males made up about 40 percent of Upolu’s butterfly population.
On Savaii, females still dominated the Blue Moon butterfly population (99 percent) at the start of 2006, but by the year’s end, males made up nearly 40 percent.
The team ran genetic analyses to see if the parasite had somehow vanished. It hadn’t. Wolbachia was still present in butterflies from both islands. Other lab experiments indicated the males had evolved suppressor genes to shield against the parasite.


If you find yourself a member of a suddenly or unexpectedly parthenogenic species, PlagueBlog recommends tetracycline.

Sunday, July 15, 2007

Birthwort and Balkan Nephropathy

Via ProMED-mail: New Scientist reports on the likely solution to a longstanding mystery.

Since it was first formally recognised in 1956, the disease called endemic Balkan nephropathy has perplexed experts, who have considered various explanations, including groundwater contamination.
Unlike most patients with kidney failure, people with the Balkan illness often have healthy blood pressure. Nonetheless, as their kidneys begin to fail they require dialysis and about half of them eventually develop a rare cancer of the upper urinary tract.
Arthur Grollman, at the University at Stony Brook, New York, US, did not expect to discover birthwort as the cause of this kidney disease when he set out for the region a few years ago. Instead, he had hypothesised that herbal remedies were to blame for this nephropathy.
[... H]e surveyed patients in dialysis clinics in the region on whether they had taken any herbal medicines. But none reported taking such supplements.
Disappointed his theory had proved wrong, Grollman headed for home – but not before killing a final afternoon in a library in Zagreb, the Croatian capital.
There, he came across a striking description from the 1930s about how horses in the region had developed kidney failure after grazing on a plant known as Aristolochia clematis, also known as birthwort. Grollman immediately cancelled his flight and set off to meet Balkan farmers.
A survey of their fields and mills revealed that some of their wheat was indeed contaminated with Aristolochia clematis seed. Back in the lab, Grollman and his colleagues examined kidney samples from Croatian nephropathy patients. They found the same telltale signs of DNA damage linked to Aristolochia clematis as seen in animal studies.


PlagueBlog recommends weeding the wheat.

Friday, July 13, 2007

Another Typhoid Traveller

Via ProMED-mail: The Sydney Morning Herald reports on Australia's first polio case in 21 years, imported from Pakistan by plane:

A 22-year-old man carrying the disease was in isolation in a Melbourne hospital last night and health authorities were trying to track down the 249 passengers who shared his July 2 Thai Airlines flight from Bangkok to Melbourne.
Those on flight TG999 were urged to contact the health information hotline on 1800 004 599, which is open between 8.30am and 10pm.

Thursday, July 12, 2007

Autism and Vaccines Again

Via Gene Expression: the UK Times reports on the latest autism and MMR controversy.

One of the two team members reported as resurrecting the discredited theory that MMR causes autism is Dr Carol Stott, a developmental psychologist who once worked at ARC. Baron-Cohen says she left ARC some time ago. She is now listed as a member of staff at Thoughtful House, a research centre in developmental disorders in Texas. Thoughtful House is run by Dr Andrew Wakefield, the gastroenterologist who first raised the possibility of a MMR-autism link in 1998. The other figure named as having revived the MMR-autism link was Dr Fiona Scott, who still works at ARC as an honorary research associate and runs training courses on how to diagnose autism. Scott has issued a statement denying that she privately believes in any link between MMR and autism.
Baron-Cohen says the news story is alarmist and wrong. He does not believe that MMR has anything to do with autism. “We are gobsmacked, really, at how this draft report has got out,” Baron-Cohen says. “It was only in the hands of the authors – about half a dozen people. There are three professors listed, including me, and none of us was contacted. It was also seen by two PhD students for whom I have the utmost respect because they are very careful scientists.
“I don’t believe that the MMR vaccine causes autism and I don’t believe that there are hidden environmental reasons for any rise in cases. For the moment, we should assume [any rise] is more to do with diagnostic practice.”

Wednesday, July 11, 2007

Autism, Bipolar Disorder, and Schizophrenia

Via Gene Expression, a PNAS article that correlates susceptibility to 161 diseases, pairwise, with special attention to autism, bipolar disorder, and schizophrenia. They interpret the correlations as overlap in the genetic mechanisms of (susceptibility to) the various diseases.

Our analysis suggests that, instead of following the familiar model of ‘‘unique malady–unique (disjoint with others) set of broken genes’’ applicable to most Mendelian disorders (Fig. 2D), most complex phenotypes are probably rooted in genetic variation that is significantly shared (in either a competitive or cooperative manner) by multiple disease phenotypes (Fig. 2E).
Phenotypes of non-Mendelian disorders are often defined with a considerable degree of fuzziness, especially those that are neurological: it is not uncommon to define a neuropsychiatric disease phenotype as comprising, for example, at least five of a list of 10 symptoms (4). This fuzziness arises because, in many cases, the observed disease is a heterogeneous collection of multiple maladies that have partially similar symptoms and potentially different genetic causes. However, these genetically heterogeneous maladies are combined because of the history of disease identification and the incompleteness of our knowledge about the disease causes.
Our interpretation of genetic overlap among pairs of disorders does not exclude the possibility that one disorder can cause the other. For example, it is possible that comorbidity of autism (or schizophrenia, or bipolar disorder)with infectious and autoimmune maladies indicates that the neurodevelopmental disorder can be triggered by different developmental insults, including viral or bacterial infection, or an autoimmune disease launched by a benign allergen. Another possibility is that the same molecular features that make a child more susceptible to infection or to autoimmune attack have a pleiotropic effect on brain development and function.


For the full list of overlaps, see the appendices. Appendix 1 has more pretty pictures, while 4 and 5 have some easier-to-read tables. Here's the pretty picture for plague (click to enlarge):

Monday, July 09, 2007

CDC Closes Texas A&M's Biodefense Lab

Via ProMED-mail: CIDRAP reports that the CDC has shut down Texas A&M's biodefense research lab for failure to report accidents.

In April, the Sunshine Project reported that a Texas A&M researcher had been infected with Brucella after a February 2006 aerosol chamber mishap and that the school did not immediately notify the CDC as required by federal law. Five days ago, the watchdog group reported that the exposure of three other Texas A&M workers to C burnetti, which causes Q fever, was confirmed in April 2006 but also was not reported to the CDC.


The CDC noted other concerns as well:

In the Jun 30 letter, the CDC outlined the concerns it has about the lab, which include the adequacy of biosafety plans, security of the facility from unauthorized visitors, occupational safety protocols, authorization from the CDC to work with certain agents, and compliance with federal select agent regulations.

Sunday, July 08, 2007

Nosocomial HIV Transmission in Africa

Via Gates of Vienna: Medilinks has an October 2002 article from the International Journal of STD & AIDS on HIV infections in sub-Sahara Africa not explained by sexual or vertical transmission.

An expanding body of evidence challenges the conventional hypothesis that sexual transmission is responsible for more than 90% of adult HIV infections in Africa. Differences in epidemic trajectories across Africa do not correspond to differences in sexual behavior. Studies among African couples find low rates of heterosexual transmission, as in developed countries. Many studies report HIV infections in African adults with no sexual exposure to HIV and in children with HIV-negative mothers. Unexplained high rates of HIV incidence have been observed in African women during antenatal and postpartum periods. Many studies show 20%-40% of HIV infections in African adults associated with injections (though direction of causation is unknown). These and other findings that challenge the conventional hypothesis point to the possibility that HIV transmission through unsafe medical care may be an important factor in Africa's HIV epidemic.


Although the authors of the article dance around the issue, the primary cause of the HIV epidemic in Africa appears to be the reuse of hypodermic needles. Both Marburg and Ebola have been spread nosocomially in Africa, but in that case the evidence is so immediate and bloody that no one questions it.

PlagueBlog recommends against seeking medical care in sub-Saharan Africa.

Tuesday, June 26, 2007

Apocalyptic XDR-TB

Via ProMED-mail: Reuters reports on the "apocalyptic scenario" of an epidemic of extremely drug-resistant tuberculosis and a return "to the pre-antibiotic era":

XDR-TB cases are particularly difficult to treat, and a patient could infect other people for years, according to Mario Raviglione, director of the WHO's Stop TB Department.
"That is the big threat here. If you have more and more of these cases, you will automatically magnify the problem by having transmission going on to other individuals ... Once they become infected they are sort of a time bomb," Raviglione said.
"If this is kept unchecked and goes on, then you may also see an apocalyptic scenario where the present epidemic of TB is replaced by an epidemic of TB which is now fully resistant to everything," he added.


it's hard to maintain one's alarmist reputation when the WHO is more alarmed than you are...

Tuesday, June 19, 2007

Indonesia Hits 100

Via ProMED-mail: the WHO reports that Indonesia has reported its 100th human case of bird flu and 80th bird flu fatality.

A 26-year-old male from Riau Province developed symptoms on 3 June, was hospitalized on 6 June and died in hospital on 12 June. Investigations into the source of his infection indicate exposure to sick and dead poultry.

Tuesday, May 29, 2007

The Typhoid Traveller

Pretty much everyone, including The New York Times, reports on the travelling tuberculosis patient who may have infected two intercontinental flights full of people before being picked up sneaking home from Montreal and quarantined by the CDC--reportedly the first person to be subject to a federal isolation order since a smallpox patient was quarantined in 1963.

The Atlanta Journal-Constitution has an interview with the Typhoid Traveller in which he tells his side of the story of his ill-fated honeymoon:

Katkowsky and CDC officials say they only knew that the man's TB was resistant to many drugs before he left, but that the tests showing he had the most serious form of TB — XDR TB — only came back after he was in Europe. The test results came back on May 21, Fulton County officials said.
The man says he and his bride were in Rome on their honeymoon when they got a message to call the CDC. The CDC official said that they needed to cancel their trip and return home and that the CDC would call the next day with travel information.
The patient says he and his wife canceled plans to move on to Florence the next day as they awaited the CDC's instructions.
The next day, instead of giving the couple travel arrangements, the man said a CDC staff member told him he'd need to turn himself into Italian health authorities the next morning and agree to go into isolation and treatment in that country for an indefinite period of time.
"I thought to myself: 'You're nuts.' I wasn't going to do that. They told me I had been put on the no-fly list and my passport was flagged," the man said.
The man said the CDC told him he could not fly aboard a commercial airliner with his disease. "We asked about the CDC jet and they said no, there wasn't funding in the budget to use the jet," he said.

Friday, May 25, 2007

Don't Eat the Squirrels

Via ProMED-mail: Channel 4 in Denver reports that a hooded capuchin monkey in the Denver Zoo died of plague.

The zoo learned late Friday from the Colorado Department of Public Health and Environment that the hooded capuchin monkey had the plague.
The monkey seemed lethargic last Tuesday and was found dead Wednesday morning by a zookeeper, zoo officials said.
It's unclear if the monkey contracted the disease from infected fleas, or if the monkey ingested the remains of an infected squirrel. The zoo suspects it's from ingestion.
None of the other monkeys in the troop have displayed signs of illness, but antibiotics have been administered as a precaution.


PlagueBlog recommends against eating squirrels, especially if they appear ill or dead before their time.

Sunday, May 20, 2007

Another Stay for Smallpox

Via ProMED-mail: Reuters AlertNet reports on another stay of execution for US and Russian smallpox stocks until sometime after 2011.

The 60th annual World Health Assembly, the top decision-taking body of the United Nations agency, reaffirmed a previous commitment to getting rid of the remaining stockpiles but agreed to postpone any decision on when this should happen until its 2011 meeting.
In 2010, the WHO secretariat will carry out a review of all research undertaken and still planned in order that the "64th World Health Assembly may reach global consensus on the timing of the destruction of existing variola virus stocks."
A previous 2002 deadline for destroying smallpox had been waived by the WHO until new vaccines or treatments for smallpox were found, after the United States said it would keep stocks on hand to combat any re-emergence of the disease.


I, for one, am glad I was vaccinated against this sadly continuing threat.

Friday, May 18, 2007

Adopt-A-Rabid-Bat Month

Via ProMED-mail: the Casper Star-Tribune reports on a case of rabies exposure at Trinity Lutheran School in Riverton, Wyoming:

A staff member on May 9 discovered the bat in the school basement, where it was captured and stored in a cage in Steve Coniglio's seventh- and eighth-grade classroom.
It was also displayed in other classrooms, and students fed it crickets through the cage. No one is believed to have touched the bat directly, head teacher Susan Tucker said.
School officials notified a local veterinarian after the bat died suddenly on May 11. The state Department of Health was called in once the animal tested positive for the rabies virus.
Coniglio and a teacher's aide who washed the cage without protective gloves after the bat died are receiving the rabies vaccine as a precaution.


PlagueBlog recommends getting your pets from an animal shelter, pet store, or reputable breeder.

Thursday, May 17, 2007

Herpes vs. Plague

Via Gene Expression: in a letter to Nature, researchers claim that latent herpes infections prompt increased immune response to bacterial infections, including Yersinia pestis.

Mice latently infected with either murine gammaherpesvirus 68 or murine cytomegalovirus, which are genetically highly similar to the human pathogens Epstein–Barr virus and human cytomegalovirus, respectively, are resistant to infection with the bacterial pathogens Listeria monocytogenes and Yersinia pestis. Latency-induced protection is not antigen specific but involves prolonged production of the antiviral cytokine interferon-gamma and systemic activation of macrophages.

Tuesday, May 15, 2007

Ocular Syphilis

Via ProMED-mail: The West Australian reports on a resurgence of ocular inflammation caused by untreated syphilis infections:

Homosexual men are most commonly affected, with infectious disease experts predicting the epidemic will spread through gay communities nationwide with time.
Dr Amaratunge says eye-related syphilis is relatively uncommon, with 15 cases expected in Victoria this year, but numbers are rising fast.
Fewer than 10 per cent of people who catch the disease develop symptoms in their eyes, causing redness, pain, light sensitivity and loss of vision.
But in those who do, 25 per cent will have no other symptoms of the syphilis and therefore often have no idea they have the debilitating condition.

Thursday, May 03, 2007

Mmm-mmm Melamine, Part II

Via ProMED-mail: the Washington Post reports on more Chinese melamine in the food chain:

At least 2.5 million broiler chickens from an Indiana producer were fed pet food scraps contaminated with the chemical melamine and subsequently sold for human consumption, federal health officials reported yesterday.
Hundreds of other producers may have similarly sold an unknown amount of contaminated poultry in recent months, they added, painting a picture of much broader consumption of contaminated feed and food than had previously been acknowledged in the widening pet food scandal.
[...]
Meanwhile, the FDA expanded the number of plant-based protein products from China on its "do not import" list, pending the completion of further tests on various kinds of glutens, protein concentrates and other products.
At the center of the problem are pet foods spiked with melamine, a mildly toxic chemical that can make food appear to have more protein than it does. Most of the food went to pets, but scraps were sold in February to the Indiana poultry producer, officials said. The contaminated material may have made up about 5 percent of the chickens' total food supply.
That small fraction, and the fact that people, unlike pets, do not eat the same thing day after day, suggests that consumers who ate contaminated pork or chicken would probably have ingested extremely small doses of melamine, well below the threshold for causing health effects, officials said. Experts conceded, however, that they know little about how the toxin interacts with other compounds in food.

Mmm-mmm Melamine

Via ProMED-mail: The New York Times reports that feed in China is routinely adulterated with the poisonous coal derivative melamine:

For years, producers of animal feed all over China have secretly supplemented their feed with the substance, called melamine, a cheap additive that looks like protein in tests, even though it does not provide any nutritional benefits, according to melamine scrap traders and agricultural workers here.
“Many companies buy melamine scrap to make animal feed, such as fish feed,” said Ji Denghui, general manager of the Fujian Sanming Dinghui Chemical Company, which sells melamine. “I don’t know if there’s a regulation on it. Probably not. No law or regulation says ‘don’t do it,’ so everyone’s doing it. The laws in China are like that, aren’t they? If there’s no accident, there won’t be any regulation.”
Melamine is at the center of a recall of 60 million packages of pet food, after the chemical was found in wheat gluten linked this month to the deaths of at least 16 pets in the United States.


PlagueBlog recommends avoiding any human food, animal feed, or edible components thereof originating in China. And the inedible components, too.

Monday, April 30, 2007

Necrotic Arachnidism

Via ProMED-mail: Press Peru reports 2264 bites, three of them fatal, by the Chilean recluse spider in 2006. Loxosceles laeta and related recluse spiders are also known as violin, corner, fiddleback, or domestic spiders.

Here's some recluse information from the Hobo Spider Web Site:

The recluse spiders, genus Loxosceles, belong to a unique family of arachnids known as the Sicariidae, or six-eyed sicariid spiders. The sicariids have six (rather than the typical eight) eyes, arranged in a horseshoe pattern in three clusters of two eyes each. The family consists not only of the recluse spiders, but also of the six-eyed crab spiders, genus Sicarius, of Central and South America, and South Africa. Recluse spiders were the first spider group to be recognized as a causative agent of the disease state now known as necrotic arachnidism, and this condition, when caused by a recluse spider, is properly termed loxoscelism. Loxoscelism was first recognized in 1872 when Chilean physicians linked a peculiar skin lesion known as the "gangrenous spot of Chile" to bites by the Chilean recluse spider, Loxosceles laeta. The brown recluse, L. reclusa, became the first U.S. spider associated with necrotic arachnidism in 1957, when it was linked to severe bites in the midwest. All recluse spiders, as well as the six-eyed crab spiders, are now considered venomous to humans.


Brown recluses are not as common in the United States as people imagine. Bites reported in areas outside its range, such as Massachusetts, are likely due to other causes---for example, the local Yellow Sac spider:

Cheiracanthium mildei was first identified as a cause of necrotic arachnidism in 1970, when it was linked with skin lesions in the Boston, Massachusetts area (where it is the most common spider found in houses); it is also common in houses in New York City, and may well be the cause of recent "brown recluse bite" rumors circulating there. In the late 1970's and early 1980's mildei produced a significant number of bites in the Provo, Utah area. C. inclusum has been reported responsible for bites in Georgia and southwestern Canada; bites by this species are probably far more common and widespread than this however, and it is likely that more reports will surface as Cheiracanthium species become better known as clinically significant spiders.

Saturday, April 28, 2007

Plague Squirrel Found in Denver

Via ProMED-mail: the Colorado Department of Public Health reports a squirrel die-off near City Park. Only one dead squirrel was tested and it came back positive for plague.

John Pape, an epidemiologist who specializes in animal-related diseases for the department's Disease Control and Environmental Epidemiology Division, said, "Plague is a disease seen every year among rodent populations in rural areas of Colorado, including the Front Range. It is unusual to find plague in the center of an urban area although it has happened before."


ProMED-mail cites a 1970 publication claiming that a previous plague epizootic in Denver squirrels was discovered in 1968 only after it had led to a human plague case.

Sunday, April 22, 2007

Bird Flu Vaccine Approved

Via ProMED-mail: on Wednesday the FDA announced the approval of an H5N1 vaccine for humans:

The vaccine was obtained from a human strain and is intended for immunizing people 18 through 64 years of age who could be at increased risk of exposure to the H5N1 influenza virus contained in the vaccine. H5N1 influenza vaccine immunization consists of two intramuscular injections, given approximately one month apart. The manufacturer, sanofi pasteur Inc., will not sell the vaccine commercially. Instead, the vaccine has been purchased by the federal government for inclusion within the National Stockpile for distribution by public health officials if needed. The vaccine will be manufactured at sanofi pasteur's Swiftwater, Pa., facility.

Thursday, April 19, 2007

Catpox

Via ProMED-mail: Eurosurveillance surveys recent (human) cowpox cases in Germany, increasingly via cats, and speculates on the cause:

Before the global eradication of smallpox (announced by the World Health Organization in 1979), live vaccinia virus was commonly used as a vaccine against variola virus. Vaccinia virus is closely related to variola virus and other members of the orthopoxviruses and induces cross-immunity [13]. In the course of the eradication of variola virus, vaccinations of children were stopped in Germany in the 1970s due to severe vaccination-related complications. Thus, there is a widening immunisation gap in a population that was previously protected by this vaccine not only against smallpox, but also had an inprecisely defined protection against other forms of orthopoxviruses, e.g. cowpox and monkeypox. Over the last two years, nine patients suspected of suffering from poxvirus infection were examined at the German consultant laboratory for poxviruses. Four of the patients, including the two cases described above, were positive for cowpox virus. [...] This represents an increase in diagnosed human cowpox infections in Germany during the past years. Whilst it cannot be excluded that this is due to a reporting bias, this increase may reflect the fact that a smaller proportion of people have immunity against cowpox virus after the stop of smallpox vaccinations. Interestingly, recent human cowpox cases were observed in people too young to be vaccinated against smallpox.

Tuesday, April 17, 2007

Give It To Everybody

The FUMP has a funny STD song: Give It To Everybody by Sudden Death, It's an explicit parody of "All That I Need" by Busta Rhymes. Here's the tamest sample of the lyrics I could find:

Julie-Anne just gave it to Bob, who did Jill and Jean,
who shared it with me, and now you got it (repeat)
Anthony just gave it to me, I gave it to you
You spread it around, so we all got it (repeat)

Thursday, April 05, 2007

Type O for All

Via GeekPress: The BBC reports that scientists have found a possible way to change the type of donated blood to O:

The new technique works by using bacterial enzymes to cut sugar molecules from the surface of red blood cells.
After a search of 2,500 fungi and bacteria the researchers discovered two bacteria - Elizabethkingia meningosepticum and Bacterioides fragilis - which contained potentially useful enzymes.
They found that enzymes from both bacteria were able to remove both A and B antigens from red blood cells.

Wednesday, March 14, 2007

A Plan to Trade in Death

Via an unnamed source: the AP reports on a new bird flu futures market:

Such markets have sometimes proved controversial. In 2003, the Pentagon dropped plans for a futures market that would have allowed traders to profit from accurate predictions on terrorism, assassinations and other events in the Middle East. Some lawmakers attacked the idea as immoral; U.S. Senator Tom Daschle of South Dakota described it as a "plan to trade in death."
Organizers predicted the bird flu market should prove less controversial, and the New Jersey-based Robert Wood Johnson Foundation cautiously agreed.
"It might be considered controversial if it's not well understood," said the philanthropy's Robert Hughes.
He noted that public health experts won't be gambling their own money, so opportunities for financial gain are extremely limited.
Also worth noting is the buy-in of ProMed, a respected disease-monitoring program of the International Society for Infectious Diseases. ProMed, with a staff of 30, collects disease updates and e-mails them to 40,000 international members, making it the largest such service in the world.

Friday, March 09, 2007

Don't Drink the Water

Via ProMED-mail: The FDA reports a recall of "Jermuk" Brand Mineral Water from Armenia, which may be contaminated with arsenic:

The Food and Drug Administration (FDA) is warning consumers not to drink certain brands of mineral water imported from Armenia due to the risk of exposure to arsenic, a toxic substance and known cause of cancer in humans. Symptoms of acute arsenic exposure usually occur within several hours of consumption. The most likely effects include nausea, vomiting, diarrhea, and stomach pain. Over the period of a few days to weeks, the kidneys, liver, skin, and cardiovascular and nervous systems could be affected. Extended exposure could lead to cancer and death.

Wednesday, March 07, 2007

The Return of the Virion

Via ProMED-mail: Yale Daily News reports on research by Dr. Laura Manuelidis, the head of neuropathology at Yale's School of Medicine, into viral explanations for Creutzfeldt-Jakob and related diseases:

The research team’s goal was to try to identify viral particles in infected cells. They infected cell lines with either scrapie (a sheep disease related to mad cow) or CJD agents and found virus-like particles that did not contain prion protein. An abundance of these particles was related to high levels of infectivity, which was not true of the presence of prion proteins.
“People hypothesize that prion proteins are infectious, but they’re probably part of the disease, not the infectious agent itself,” Manuelidis said.
The virus-like particles had been found by other researchers but were largely ignored. They were first identified in 1968 in synaptic regions of scrapie-infected brain and later found in many other animals with different TSEs. But Manuelidis said that researchers apparently forgot about them once the prion hypothesis became dominant.

Monday, March 05, 2007

Weekend of E. Coli

Channel 7 reports that this weekend's boil-water order in Woburn, Massachusetts(1) has been rescinded after the smoking squirrel(2) was discovered inside the suspect water tank:

That tank is being taken care of, and the mayor has an interesting theory at what caused the problem, a small animal was found inside the tank.
Crews disinfected the water supply by pumping in additional chlorine to affected areas.


(1) PlagueBlog recommends against drinking the water in Woburn, Mass. under any circumstances, boiled or not, boil order or not, brown or not, eating through the pipes or not, for at least a hundred years.

(2) "Smoking squirrel" is a term of art and should not be taken literally. The report did not specify the animal found.

Friday, March 02, 2007

Worse than the Disease

Via ProMED-mail: The Monitor reports nine deaths from [pneumonic] bubonic plague in Masindi, Uganda:

The first measure taken in Masindi was to stop people from sleeping on the floor.
Dr Zaramba said this reduced the prevalence of rats. Smearing floors with cow dung also helps contain the spread of plague as it discourages rats from entering domestic environments.


At least it will discourage humans from sleeping on the floor. PlagueBlog recommends rat poison.

Tuesday, February 27, 2007

The Left Hand of Disease

Gene Expression reports on "a new study in Epidemiology on longevity and handedness in a large, representative sample of Dutch women (Ramadhani et al. 2007)."

Table 2 shows that, after adjustment for age, SES, BMI, and cigarette smoking status, left-handed women had a 1.36 times higher risk of dying from all causes than non-left-handed women. The adjusted HR for total mortality, after excluding the first 5 years of follow-up time, was 1.58 (95% CI = 1.03--2.42). With regard to cancer mortality, left-handed women had a 1.7 times greater risk of dying from any type of cancer (CI = 1.0--2.7), a 4.6 times higher risk of dying from colorectal cancer (1.5--14), and a 2.0-fold higher risk of dying from breast cancer (0.83--4.6). Handedness was weakly associated with overall mortality from diseases of the circulatory system (1.3, 0.54--3.3), although left-handed women had a 3.7 times greater risk of dying from cerebrovascular diseases than non-left-handed women.


See the link for more co-symptoms of left-handedness, and for the most likely explanation:

One thing seems pretty clear, though: common cases of deviance from Darwinian fitness are most likely caused by environmental insults, with pathogens being the most obvious culprit (see Cochran, Ewald, & Cochran 2000 for the rationale).

Monday, February 26, 2007

A Drug for Down Syndrome

United Press International reports on pentylenetetrazole (PTZ) as a treatment for Down Syndrome (trisomy 21):

Craig Garner, Fabian Fernandez and colleagues found that, after they gave mice genetically engineered to develop Down syndrome 17 daily doses of PTZ in milk, they performed as well as their wild-type counterparts when asked to identify novel objects and navigate a maze that simulated difficulties faced by human children and adults with Down syndrome.
The authors said that they thought this occurred because PTZ blocks the action of a neurotransmitter called GABA that is overproduced in people with Down syndrome and inhibits their ability to learn. When the amount of GABA in the brain was brought into balance with other neurotransmitters, normal learning was possible.


If you're wondering how they gave mice, who only have 20 pairs of chromosomes to start with, a trisomy for a chromosome they don't have, here's a BBC report from 2005 on doing just that.

Friday, February 16, 2007

The Smoking Peanut Butter

The AP reports on the salmonella outbreak traced to Peter Pan Peanut Butter and another ConAgra product:

Nearly 300 people in 39 states have fallen ill since August, and federal health investigators said they strongly suspect Peter Pan peanut butter and certain batches of Wal-Mart's Great Value house brand -- both manufactured by ConAgra Foods Inc.
Shoppers across the country were warned to throw out jars with a product code on the lid beginning with ''2111,'' which denotes the plant where it was made.
How the dangerous germ got into the peanut butter was a mystery. But because peanuts are usually heated to high, germ-killing temperatures during the manufacturing process, government and industry officials said the contamination may have been caused by dirty jars or equipment.


This outbreak of a rare salmonella strain has been going on since August:

The strain in this outbreak, Salmonella serotype Tennessee, is comparatively rare, as is salmonella contamination of peanut products, said Caroline Smith DeWaal, director of food safety at the Center for Science in the Public Interest.
It may have taken a long time to identify peanut butter as the source because ''it's just not one of the first things you'd suspect,'' Smith DeWaal said.

Tuesday, February 13, 2007

Where have all the gametes gone?

Strangely enough, an unnamed source was just telling me last night about theories of vasectomy-induced autoimmune reactions to all those trapped sperm. Today Reuters reports on research linking vasectomies to two forms of dementia:

Researchers at Northwestern University in Illinois, writing in the journal Cognitive and Behavioral Neurology, linked this male sterilization surgery to a neurological condition called primary progressive aphasia, or PPA.
They surveyed 47 men with the condition being treated at Northwestern's Cognitive Neurology and Alzheimer's Disease Center, as well as 57 men who did not have PPA. Their ages ranged from 55 to 80.
Of those with primary progressive aphasia, 40 percent had undergone a vasectomy, compared with 16 percent of the others. Those with PPA also suffered the ailment an average of four years earlier than the others.
Preliminary data also linked vasectomies to another form of dementia involving behavioral changes. Among 30 men with frontotemporal dementia, more than a third had undergone a vasectomy, the researchers said.


The lead researcher postulates an autoimmune response:

The study did not look at the mechanism behind any link between PPA and vasectomies, but Weintraub said it may be because the surgery allows sperm to leak into the blood. Antibodies produced by the immune system in response to the sperm might trigger damage that causes dementia, she said.

Monday, February 12, 2007

The New Hysteria

Via GeekPress: Nature reports on research into the origins of the psychological notion of repressed memory:

To see how long the idea of repressed memories have been around, a group of psychologists and literature scholars turned to historical writings.
They could not find a single description of repressed memory, also referred to as dissociative amnesia, in fiction or factual writing before 1800.


Apparently it was all just a Freudian slip...

Sunday, February 04, 2007

DCA Research Page

The University of Alberta now has a webpage of DCA Reseach Information, including plans for clinical trials:

Investigators at the University of Alberta have recently reported that a drug previously used in humans for the treatment of rare disorders of metabolism is also able to cause tumor regression in a number of human cancers growing in animals. This drug, dichloroacetate (DCA), appears to suppress the growth of cancer cells without affecting normal cells, suggesting that it might not have the dramatic side effects of standard chemotherapies.
At this point, the University of Alberta, the Alberta Cancer Board and Capital Health do not condone or advise the use of dichloroacetate (DCA) in human beings for the treatment of cancer since no human beings have gone through clinical trials using DCA to treat cancer. However, the University of Alberta and the Alberta Cancer Board are committed to performing clinical trials in the immediate future in consultation with regulatory agencies such as Health Canada.

Saturday, February 03, 2007

Bagged and Tagged

PlagueBlog was recently upgraded to the new Google Blogger, which made it possible to label all previous posts by disease. Not surprisingly, flu came out first, while Marburg, the eponymous plague, and the transmissible spongiform encephalopathies (TSE) all made a respectable showing.

On the lighter side, there are some non-disease-specific categories: PlagueFun, don't try this at home (formerly known as the Don't Kiss the Chickens department), paging Dr. Frankenstein (a.k.a., don't resurrect the Spanish Flu in your BSL 3 lab just because you can), and PlagueBlog recommends (...cooking the blood of your H5N1-infected poultry before drinking it to protest your government's half-hearted attempts to stamp out bird flu, for example).

Friday, February 02, 2007

Bird Flu Kills At Least One Nigerian

Reuters reports on the first human death from bird flu in Nigeria:

The 22-year-old died after feathering and disembowelling an infected chicken. She was from Lagos, the commercial capital of Africa's most populous country, Information Minister Frank Nweke said.
Test [sic] on three other victims, one of them the woman's mother, were inconclusive.
Nigeria was the first African nation to detect the H5N1 virus in poultry last year and had conducted tests on 14 people suspected of having the virus.


The WHO is taking it in stride:

World Health Organisation spokesman Gregory Hartl said a human case of bird flu in Nigeria was to be expected because of the experience in other countries, such as Indonesia, with huge poultry populations where chickens and hens live in close proximity to humans.
"It does not change anything from a public health point of view," Hartl said. "It had to happen sooner or later."

Monday, January 29, 2007

Cat Flu

Via ProMED-mail: New Scientist reports on the implications of widespread H5N1 infection among Indonesia's cats.

Chairul Anwar Nidom of Airlangga University in Surabaya, Indonesia, told journalists last week that he had taken blood samples from 500 stray cats near poultry markets in four areas of Java, including the capital, Jakarta, and one area in Sumatra, all of which have recently had outbreaks of H5N1 in poultry and people.
Of these cats, 20 per cent carried antibodies to H5N1. This does not mean that they were still carrying the virus, only that they had been infected - probably through eating birds that had H5N1. Many other cats that were infected are likely to have died from the resulting illness, so many more than 20 per cent of the original cat populations may have acquired H5N1.
[...]
Osterhaus emphasises that the cat infections still pose a potential threat. "We know the 1918 pandemic was a bird flu virus that adapted to mammals in some intermediate mammalian host, possibly pigs," he says. "Maybe for H5N1 the intermediate host is cats." If similar percentages of cats are infected at every outbreak location, there must have been many thousands of cat infections since the virus emerged, compared to 267 confirmed cases in humans. Every sick cat is a chance for the virus to adapt, and with renewed outbreaks this year in birds, people or both in China, Indonesia, Japan, South Korea, Hong Kong, Vietnam, Thailand, Egypt and Nigeria, it is getting plenty of such chances.

Monday, January 22, 2007

A Cure for Cancer?

Via GeekPress: NewScientist.com reports on dichloroacetate (DCA), a cheap, unpatented potential cancer drug:

Evangelos Michelakis of the University of Alberta in Edmonton, Canada, and his colleagues tested DCA on human cells cultured outside the body and found that it killed lung, breast and brain cancer cells, but not healthy cells. Tumours in rats deliberately infected with human cancer also shrank drastically when they were fed DCA-laced water for several weeks.
DCA attacks a unique feature of cancer cells: the fact that they make their energy throughout the main body of the cell, rather than in distinct organelles called mitochondria. This process, called glycolysis, is inefficient and uses up vast amounts of sugar.

Saturday, January 20, 2007

Playing with the Spanish Flu

Nature has a Web focus on the 1918 flu virus. For a free account of the latest on Frankenstein's reconstituted flu virus, see this press release from the University of Wisconsin-Madison:

By infecting monkeys with the virus, the team was able to show that the 1918 virus prompted a deadly respiratory infection that echoed historical accounts of how the disease claimed its victims.


Shocking! But wait, there's more:

Importantly, the new work shows that infection with the virus prompted an immune response that seems to derail the body's typical reaction to viral infection and instead unleashes an attack by the immune system on the lungs. As immune cells attack the respiratory system, the lungs fill with fluid and victims, in essence, drown.


Somehow I doubt anyone spent the last 90 years believing that the victims were drowning in liquid flu virus. But on a more optimistic note,

The same excessive immune reaction is characteristic of the deadly complications of H5N1 avian influenza, the strain of bird flu present in Asia and which has claimed nearly 150 human lives, but has not yet shown a capacity to spread easily among people.
"What we see with the 1918 virus in infected monkeys is also what we see with H5N1 viruses," Kawaoka says, suggesting that the ability to modulate immune response may be a shared feature of the most virulent influenza viruses.


At least these guys are playing with Frankenstein's Flu at biosafety level 4 this time:

In the new study, conducted in a high-level biosafety laboratory (BSL 4) at the Public Health Agency of Canada's National Microbiology Laboratory, seven primates were infected with the reconstructed 1918 virus. Clinical signs of disease were apparent within 24 hours of infection, and within eight days, euthanization was necessary. The rapid course of the disease mirrors how quickly the disease ran its course in its human victims in 1918.