Health Officials Say Disease Not Contagious
Question: Is anthrax contagious?
Answer: No. Direct person-to-person spread of anthrax is extremely unlikely, if it occurs at all, according to health officials.
Q: How does the disease spread?
A: The anthrax bacterium, Bacillus anthracis, forms a spore--somewhat like a tiny, hard-shelled ball--when it is not inside the body of a person or animal. The spores can spread through the air. They can also survive buried in the soil for many years.
Q: Can spores be carried on a person’s clothes and transmitted to other people?
A: Yes, but a large number of spores are generally required to infect a person, so transmission via clothing would usually take place only if the carrier was heavily contaminated.
Q: Can experts trace anthrax?
A: Using DNA typing, researchers can distinguish one strain of anthrax from another. There are hundreds of different strains. Many of the strains, however, have been widely dispersed around the world, so identifying a strain does not necessarily tell where the anthrax is from.
Q: Are some strains more dangerous than others?
A: Yes, at least one strain is so weak that it is not dangerous and is used as a vaccine. But all naturally occurring strains of anthrax can be treated with antibiotics.
Q: Are there genetically engineered strains that resist antibiotics?
A: Perhaps. During the Cold War, the Soviet Union and the United States experimented with anthrax. There has also been evidence that Iraq has attempted to produce anthrax weapons.
Q: What does “weaponized” anthrax refer to?
A: In order for anthrax to be useful as a weapon against large numbers of people, it would have to be processed in a way that would allow large numbers of spores to be widely dispersed in the air in particles that would be the proper size to be inhaled and lodge themselves in the lungs. Genetic engineering could also, in theory, make the disease more lethal.
Q: What’s the difference between “testing positive” for exposure to anthrax and having the disease?
A: A person can test positive if a spore is detected on his or her body or if a blood test reveals the antibodies against anthrax. But while one spore could trigger a positive test, that would not be enough to make a person sick. And the antibody test shows only that a person was exposed to anthrax at some point in his or her life. Particularly with the skin form of the disease, a person could have been exposed and never been aware of it.
Q: Does anthrax occur naturally in the United States?
A: Yes. The disease is no longer common, but outbreaks in sheep, cattle and other animals still occur from time to time. Usually outbreaks happen when digging disturbs soil in which diseased animals were buried years ago.
