Experts ease fears of anthrax skin infections

Associated Press

Despite the terrifying reputation of anthrax, infections of the bacteria on the skin are rarely fatal and most people get better even without treatment.

The most feared use of anthrax as a bioterrorist’s weapon is spraying it in the air so it is breathed into the lungs, causing a hard-to-diagnose infection that is almost impossible to cure once symptoms start.

The case confirmed at NBC News in New York City on Thursday was a much less aggressive form of anthrax, although both are caused by the same bacteria. That variety, cutaneous anthrax, results when anthrax spores get through a scratch or other break in the skin and cause a sore.

"The main thing for people to remember is, if you get cutaneous anthrax, it doesn’t mean you will die from it," said Dr. Philip Carter, an expert at North Carolina State University’s veterinary school.

Most people get better even without treatment. And taking standard antibiotics cures virtually everyone.

Anthrax, whether the inhaled or skin variety, is caused by spores of Bacillus anthracis, primarily a livestock disease.

On the skin, the ailment starts after three to five days with a nondescript, painless blister that is red around the edges. A day or two later, this becomes an open sore that is especially recognizable because it is black. Eventually, this dries up and leaves a black scab, which falls off after a week or two.

People typically seek treatment, and the usual approach is a common antibiotic, such as penicillin, doxycycline or Cipro. These medicines are extremely effective.

"Antibiotics and a clean gauze patch to cover it should take care of you," said Dr. Philip Hanna of the University of Michigan.

Left untreated, he said, perhaps 5 percent of cases progress to a dangerous bloodstream infection, which is almost always fatal.

Health and Human Services Secretary Tommy Thompson cautioned against hoarding antibiotics in case of anthrax exposure. "We have enough for everyone who needs it," he said.

The skin form of anthrax accounts for 95 percent of all anthrax cases in the United States. Nevertheless, it is very rare, usually causing only a case or two a year.

Anthrax is mainly a disease of grazing animals, and cutaneous anthrax is largely confined to people whose skin is exposed to the bacteria, such as ranchers, hide workers and veterinarians.

Typically, people get the anthrax sores on the head, neck and arms. Usually, the sores do not spread beyond the initial site of the bacteria’s entry into the body, and the disease is not contagious.