Anthrax Primer

With all of the stories about anthrax floating around, it's sometimes hard for the layperson to separate fact from fiction. Dr. Emily Senay of the Early Show gives us a primer on anthrax, anthrax testing, and anthrax antibiotics.

There are now 31 people who work on Capitol Hill and who have tested positive to anthrax. What exactly does that mean? Does being exposed mean that they will become ill?

That means that through nasal swabs they were able to determine that those people have definitely been exposed to anthrax. It does not mean that they are ill and it does not mean they will become ill. The good news is that these people were very rapidly started on antibiotics so they are well protected. But even if they were not started on antibiotics it does not mean they would have become ill. I believe they are all well cared for and safe from disease.

How do you test for the presence of anthrax?

The fact is there are several kinds of tests we are talking about. First, we are talking about tests done on nonhuman specimens at the scene that look for presence of anthrax. While not perfect, they can give a good idea of what you are dealing with.

Second, there are tests done on humans. There are many of these but here's a breakdown of them by category:

Swabs: These are done of the nose or other body parts and sent to labs to see if they can culture anthrax. If these are positive it means that for sure exposure occurred. It does not mean people are or will become ill.

Blood tests: They look for antibodies, which would mean that the body has reacted to anthrax. Again it does not mean the person is ill but it also indicates exposure.

Cultures: These can be done on blood, body fluids or skin lesions. In these cases, it means that disease has occurred, the organism is in the body, and the person has clinical anthrax disease.

Cipro is the only antibiotic that we've been hearing about. Are there other antibiotics that are effective against anthrax?

Yes. In fact, anthrax is sensitive to many other antibiotics including doxycycline and penicillin--not to mention that in lab tests it is sensitive to a wide variety of other antibiotics.

Are there superstrains that resist antibiotics?

No. In fact all strains so far have been susceptible to penicillin, which means they have not been genetically modified to be superstrains. The reason that Cipro has become such a superstar drug was the fear that if anthrax was used in an attack, it would have been genetically modified. So far it has not been, and good old penicillin would work just fine.

Is there more than one kind of anthrax?

There is one kind of anthrax but its mode of entry into the body determines disease.

If it is aerolsized and there are enough spores inhaled, it can cause inhalation anthrax, the worst kind. If it comes in through the skin, then it causes cutaneous nthrax. And, if enough is ingested then it causes the GI [gastrointestinal] form. One kind of bug---three ways it can get you.

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