--INCUBATION It generally takes two to five days for symptoms to appear, though in some cases, spores lodged in the lungs may take up to 60 days to germinate.
--SYMPTOMS Initially, very similar to those of the flu--fever, muscle aches, nausea and cough. After several days, as the immune system tries but fails to rid the body of the bacteria, more severe signs appear, including difficulty breathing, high fever and shock.
FATALITY RATE (if untreated) 90%
REPORTED CASES (since Sept. 11) 2
--INCUBATION One to two days
--SYMPTOMS Shortly after exposure through a cut or other break in the skin, a small, itchy bump appears. In some cases, a rash may develop. In another few days, the lesion fills up with fluid and develops into a painless ulcer 1 to 3 cm in diameter. Not long afterward, the lesion turns black, a hallmark of skin anthrax, as tissue begins to die.
FATALITY RATE (if untreated) 20%
REPORTED CASES (since Sept. 11) 6
--HOW IT MAKES YOU SICK Once inside the body, anthrax bacteria emerge from their dormant spore phase and begin to reproduce and spew out toxins, which poison tissues and cause organs to fail. Inhaling spores is most likely to result in death because the germs burrow into lung tissue, where they come in close contact with lymph vessels. These serve as the body's liquid highway, transporting nutrients, debris--and bacterial toxins--throughout the body.
Antibiotics are effective against the disease, if administered early
--MORE THAN CIPRO Despite public perception that Cipro is the ultimate-and only-treatment for anthrax, other antibiotics work equally well against the bacteria. Bayer, Cipro's maker, is simply the only company to conduct the additional testing (on animals) required to make the claim on its label. Last week the FDA fast-tracked approval for penicillin and doxycycline as well.
--THE PATENT Bayer holds the patent on Cipro until 2003. Despite congressional pressure and news that Canadian health authorities have decided to break Bayer's patent, HHS decided against permitting other companies to make generic versions of Cipro. It maintained that Cipro (Bayer is tripling production) as well as other antibiotics, would be sufficient to meet any bump in demand.
--WHAT ABOUT A VACCINE? Only one anthrax vaccine exists, made by one company, BioPort, for only one client: the U.S. military. But BioPort stopped producing the vaccine in 1998, when the FDA cited the company for lapses in quality control at its Lansing, Mich., plant. BioPort reapplied for approval last Monday, but in the interim, both the military and NIH have been pushing two newer vaccines into clinical trials, in hope of finding a vaccine with fewer side effects. Public health officials still see no need to inoculate the general public.
How we diagnose anthrax and track its source
--IS IT ANTHRAX? Several different lab tests can detect the presence of anthrax, but no single screen can give a definitive diagnosis. Culturing a sample (from the nose, for instance) and growing the bacteria is the most conclusive way to confirm anthrax, but this can take several days. Using antibodies that stick to bacterial proteins found in the blood is another less time-consuming way.
--WHERE DOES IT COME FROM? By looking at specific sections of the anthrax DNA, scientists can determine its strain and whether it has been genetically manipulated. Every sample from the recent cases tested so far comes from the same strain. It has not yet been matched with any of the known types of anthrax collected from naturally occurring outbreaks in animals.