Thursday, March 30, 2006

Fusarium keratitis

Via ProMED-mail: an outbreak of the rare fungal eye infection fusarium keratitis has "spread" from Singapore to South Florida.

In a typical year, Bascom Palmer sees an average of 21 patients with fusarium infections, virtually all among people with eye trauma that lets the fungus penetrate the cornea, the eye's clear protective coating. Only a few patients infected since 2000 have been lens wearers, Alfonso said. But so far this year, the center already has seen 21 cases, 12 among lens wearers.

Wednesday, March 29, 2006

Measles Breaking Out All Over

Via ProMED-mail: a large measles outbreak (genotype D6) around Kiev in the Ukraine has spread to Russia, Belarus, Spain, the US, and most recently Venezuela.

Dr. Jon K. Andrus, chief of PAHO's Immunization Unit, said, "As long as measles eradication is not pursued globally, imported or import-related measles cases will continue to occur in the Americas. However, the experience in several countries shows that, when high coverage with measles-containing vaccine exists, reliable detection and aggressive follow-up of suspect cases will limit the consequences of measles virus importations."


In fact eradication is being pursued in the Ukraine, but according to ProMED-mail, it has a checkered past:

The reasons for the outbreak and the predominance of illness among people aged 15 years and older are unclear, but it is consistent with what has been observed in Belarus, Kazakhstan and the Russian Federation, where a high proportion of measles cases are among persons 20-30 years of age. This older age profile could be due to lack of previous vaccination as a result of the extensive number of contraindications accepted in the former Soviet Union; falsified records; ineffective vaccine due to inadequate cold chain or poor quality control during vaccine production; a duration of immunity that is shorter than vaccines used in western Europe; or some other factor.

Tuesday, March 28, 2006

Thimerosal

Via GNXP: The Journal of American Physicians and Surgeons (Spring 2006) documents Early Downward Trends in Neurodevelopmental Disorders Following Removal of Thimerosal-Containing Vaccines:

Contemporaneously with the epidemic rise in neuro-developmental disorders (NDs), first observed in the United States during the 1990s, the childhood immunization schedule was expanded by the U.S. Centers for Disease Control and Prevention (CDC) to include several additional thimerosal-containing vaccines (TCVs). On July 7, 1999, a joint recommendation was made by the American Academy of Pediatrics (AAP) and the U.S. Public Health Service (PHS) to remove thimerosal from vaccines. A two-phase study was undertaken to evaluate trends in diagnosis of new NDs entered into the Vaccine Adverse Event Reporting System (VAERS) and the California Department of Developmental Services (CDDS) databases on a reporting quarter basis, from 1994 through 2005. Significant increasing trends in newly diagnosed NDs were observed in both databases 1994 through mid-2002. Significant decreasing trends in newly diagnosed NDs were observed in both databases from mid-2002 through 2005. The results indicate that the trends in newly diagnosed NDs correspond directly to the expansion and subsequent contraction of the cumulative mercury dose to which children were exposed from TCVs through the U.S. immunization schedule.

Friday, March 24, 2006

Flu News for Humans

CIDRAP News reports on the WHO's flu-fighting plans:

WHO has convened experts three times since December to consider a draft protocol for early containment of a pandemic flu, the document states.
To further that effort, an international stockpile of antivirals has been created with industry donations. Three million treatment courses will be ready by May for use only in an intervention to contain the virus at it source, the WHO said.
Success would depend on prompt response to suspicious clusters of human influenza cases, WHO acknowledged. The mass dispensing of antivirals would need to start within 21 days after detection of the first case of efficient human-to-human transmission. Accomplishing that implies succeeding at a number of earlier steps, including detecting the clusters, communicating quickly and accurately from the local to the international level, and quickly obtaining outside assistance in investigation and response.


Also in the flu news, New Scientist reports on why bird flu in humans is so deadly yet hard to catch:

The H5N1 virus binds to sugars on the surface of cells deep in human lungs, but not to cells lining the human nose and throat. So report the two research teams, led by Thijs Kuiken at Erasmus University in Rotterdam, and Yoshihiro Kawaoka at the Universities of Tokyo, Japan and Wisconsin at Madison, US.
This fits the few autopsies that have been performed on H5N1 victims, who had damage to the alveoli – the delicate sacs deep in the lungs, where oxygen enters the blood.
Flu normally travels between people by being sneezed out and breathed in through the nose and throat. Both groups concluded that poor binding of the H5N1 high in the respiratory tract might be why the virus has so far not been able to spread easily between people – a major factor keeping it from becoming pandemic.

Friday, March 03, 2006

Importing Bird Flu

Reuters reports that Nigeria has traced its bird flu outbreak to illegal poultry imports:

The virus known as H5N1 has spread to seven of the country's 36 states and the capital city since it was first detected in northern Nigeria on Feb. 8, but 90 percent of infected farms bought day-old chicks from one farm in Kano state, minister Frank Nweke said.
"There is a very strong basis to believe that avian flu may have been introduced into Nigeria through illegally imported day-old chicks," he said in a statement.
"Further investigations into the activities of farms where birds have tested positive to the highly pathogenic avian flu revealed that 90 percent of them patronised the Sovet Farms Ltd in Kano."
Customs agents impounded almost 200 smuggled cartons of hatching eggs at the country's main international airport in Lagos in January, he added.

Wednesday, March 01, 2006

Poultry vs. Migratory Birds

As bird flu spreads across Europe and Africa, the question of the vector remains unanswered. One camp notes that poultry farms have been the hardest hit, while backyard chickens who are more exposed to migratory bird routes remain surprisingly healthy. Bird flu, they say, follows domestic fowl along agricultural trade routes, not wild birds on their migratory routes. See, for example, GRAIN's "Fowl play: The poultry industry's central role in the bird flu crisis".

The other camp documents the migratory paths along which H5N1 has spread--from China north to Siberia and then west to either Europe or Africa. A typical story is Unless we act now, bird flu may win in the International Herald Tribune:

For at least a decade H5N1 has circulated among a small pool of migrating birds, mostly inside China, and occasionally broken out in other animals and people. Last May, however, more than 6,000 avian carcasses piled up along the shores of Lake Qinghai, in central China, one of the world's most important bird breeding sites. Most of the dead included species that hadn't previously evidenced influenza infection.
The Lake Qinghai moment was the tipping point in the bird flu pandemic. The virus mutated, evidently becoming more contagious and deadly to a broader range of bird species, some of which continued their northern migration to central Siberia. By June, Russia's tundra was, for the first time, teeming with H5N1-infected birds, intermingling with southern European species that became infected before flying home, via the Black Sea.