CDC testing other possible anthrax cases

ATLANTA, Georgia (CNN) -- In addition to the six cases of anthrax it has confirmed, the Centers for Disease Control and Prevention said Thursday it has identified "less than five" other possible cases of anthrax.

"We are working around the clock to confirm or rule out the diagnosis," said Dr. Julie Gerberding, head of infection control for CDC.

The cases involve individuals who have reported "skin lesions or exposure circumstances that are under active investigation," she said.

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They are "in large part" linked to the two cases in Florida or the three in New York City, she said. A sixth case -- involving a postal worker in New Jersey -- was confirmed later Thursday.

"We are not experiencing a national outbreak," Gerberding said, noting that the number of confirmed cases has been "limited to a few exposures. Most people have nothing to be concerned about."

The latest confirmed anthrax infection involves a Hamilton Township postal worker who tested positive for skin, or cutaneous, anthrax, acting New Jersey Gov. Donald DiFrancesco said Thursday. A second employee is a possible case, DiFrancesco said.

The other confirmed infection announced Thursday is a woman who works in CBS News anchor Dan Rather's office. She tested positive for cutaneous anthrax and is receiving antibiotics.

The other cases involve an NBC employee and the infant of an ABC producer, each of whom tested positive for the same form of the disease. Cutaneous anthrax is the more common and least severe form of the infection.

Two men in Florida contracted the inhaled form of anthrax, and one died.

More than 50 laboratory personnel are processing hundreds of specimens around the clock to determine whether suspect substances contain anthrax, she said.

The agency has sent 36 epidemiologists to Florida, New York City and Washington to "manage the response" to the cases of anthrax or anthrax exposure.

In addition, CDC has opened an operations center where operators at a bank of telephones are handling hundreds, "perhaps thousands," of calls each day, Gerberding said.

Asked whether the agency was stretched thin, she said, "Our capacity to handle threats is evolving. We're working around the clock, but we're also able to maintain our ongoing public health work, and I think, overall, the agency is in great shape to continue to lead this response from the public health perspective."

In addition to counting on efforts from the "large capacity of laboratory personnel," the agency has number of microbiologists and other experts who can be diverted to anthrax work, she said.

"It's easy to staff the labs," she said.

The world's foremost public health agency also is part of a lab response network, a system of 100 laboratories nationwide "we've been working with to train and to help assist in the assessment of agents of bioterrorism."

As the flu season approaches, the number of suspected anthrax cases may rise, since flu symptoms mimic those of anthrax, Gerberding said.

She urged anyone in a high-risk group -- the aged and people with chronic illnesses -- to get a flu shot. "Now is the time to be especially compulsive about getting that shot," she said.

There is no plan to recommend people stockpile ciprofloxacin, an antibiotic effective against the disease. The drug can have adverse side effects and should be used only when medical authorities deem it worthwhile, she added.

In addition, taking the drug unnecessarily can lead to the growth of antibiotic-resistant bacteria, she said.

For people who have adverse reactions to ciprofloxacin, other antibiotics are also effective, she said.

The agency recommended in its Morbidity and Mortality Weekly Report that children who may have been exposed to inhalation anthrax -- the most dangerous form of the disease -- take ciprofloxacin as a precaution, despite the fact the drug's package insert recommends against giving it to children.

"We want to use the drugs that we believe would be the most effective," Gerberding said, noting that the drug's risks in children are outweighed "by preventing what could be an extremely serious infectious disease."

Still, she said, the field is rapidly changing and the recommendation could change as new information emerges.