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.