Keeping a sample of the stockpile of the smallpox virus is important, according to U.S. Health and Human Services Secretary Kathleen Sebelius, in case the virus is used in germ warfare.
"We are concerned that the smallpox virus still exists outside the official laboratories and could be released intentionally or used as a virus weapon," Sebelius said at the World Health Organization’s 64th assembly, reported AFP.
According to the U.S. Food and Drug Administration, there is no treatment for smallpox; the only prevention is vaccination. The disease is highly contagious and can be fatal. There are two clinical forms: Variola major, the most severe form, which consists of a more severe rash and fever than the second form, variola minor. Variola major is the more common form, and there are four types:
- Ordinary (the most frequently seen)
- Modified (mild, occurs in previously vaccinated patients)
Variola major has a fatality rate of approximately 30 percent; flat and hemorrhagic varieties, while more rare, are typically fatal. Hemorrhagic smallpox is often not recognized as smallpox in the beginning, and has a much shorter incubation period. Additionally, vaccination provides little, if any, protection against the hemorrhagic variety, the FDA explains.
Death rates from variola minor are much lower, around one percent.
Symptoms of smallpox typically present 12-14 days after exposure, and include high fever, malaise, and prostration with a severe headache and backache. These symptoms are then followed by the appearance of a rash, which then progresses to papules, vesicles, pustules and scab lesions. The rash initially appears on the oral mucosa, face and forearms, then spreads to the body and legs. The lesions can also appear on the palms and soles. Patients are most infectious during the first week of the rash; after all scabs have separated, the patient is no longer infectious.
According to the FDA, there are two licensed smallpox vaccines: Dryvax, which was manufactured by Wyeth Laboratories, Inc., of Madison, NJ, and ACAM2000, which is manufactured by Acambis, Inc., of Cambridge, England and Cambridge, MA. Also, the FDA said, on May 2, 2005, CBER licensed Vaccinia Immune Globulin, Intravenous (VIGIV) manufactured by Cangene Corporation of Winnepeg, Manitoba, Canada; VIGIV is used to treat rare serious complications of smallpox vaccination.
The United States and Russia are reported to have the last strains of smallpox in their possession. The disease was declared eradicated as a threat to the world population in the 1980s, and members of the World Health Organization have since been at odds over the fate of the remaining strains.
"The WHO on review on the smallpox research program concluded definitely that additional research is needed to protect public health if this [germ warfare] occurred," Sebelius said. "But let me be clear,” she added, “we are committed to the eventual destruction of the virus stocks.”
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