John Zarrella: FBI casts wide net in anthrax query

John Zarrella

(CNN) -- Reports of anthrax being mailed to various groups and companies have put many organizations, as well as the U.S. government, on alert. Authorities are saying that more employees at The Sun tabloid in Boca Raton, Florida, may have been exposed to anthrax. An employee there died from inhalation anthrax earlier this month. CNN's Daryn Kagan spoke to CNN correspondent John Zarrella for more on the developments in Florida.

DARYN KAGAN: The first place (anthrax) made news was Florida. Let's go ahead and check in in Boca Raton ... where we find our John Zarrella. John, hello.

JOHN ZARRELLA: Hi, Daryn. Well, today very little activity here at the American Media Building behind me. The federal investigators, FBI agents have been in there huddled in groups, having meetings periodically, but no one has gone in or out of the building.

The FBI has brought in 80 additional agents. What they're doing is interviewing about 800 people who worked in the building or visited the building starting about August 1. That activity is, we understand, still ongoing. We may get the results of some environmental tests; 78 samples were removed from this building last week. Some of those results may come back tomorrow. A little bit uncertain there. But a lot of the heavy lifting in this case is really being done in the laboratories at the Centers for Disease Control and in facilities here in Florida.

Yesterday afternoon a report surfaced that a number of additional workers tested positive in blood tests for exposure to anthrax -- possibly. What actually took place was this: The 300 people who work in the building not only got nasal swabs, but they also were given blood tests. The results of those blood tests have come back, and a number of people -- perhaps up to five; we don't know the exact number -- showed an increased level of antibodies in their system.

What had always been the plan was to give another blood test to all 300 people. That will take place later in the week. This way, when they compare the two blood tests, if they see increased levels in the second blood test of antibodies which are germ-fighters, that could indicate the presence of anthrax in the system, or at least exposure to anthrax.

But ... that second blood test won't be taken until Wednesday or Thursday of this coming week. Those blood samples will be taken to the Centers for Disease Control for analysis and evaluation.

So we still could be a week away from actually knowing if there were any more exposure cases to anthrax beyond the three that we have established here: Bob Stevens, who passed away, and then the two other workers who worked in the mailroom here at American Media.

So again, at this point, still only the three confirmed cases of anthrax exposure here in Boca Raton.

KAGAN: John, on a very simple matter here: What do officials really mean by "exposure"? I could imagine that you could be exposed to anthrax but not get anthrax, or not get the infection. ...Is there a chance they were exposed but don't have anthrax?

ZARRELLA: Oh, absolutely. That's exactly what they mean. When you're exposed, that means you may have the spores -- the anthrax spores that they have found in nasal passages, that they found on the computer keyboard, for example. You can have spores of anthrax, the bacteria, but you may not have full-blown infection. And once you're on the Cipro (antibiotic) -- as long as you get on that Cipro before it actually takes hold in your body -- you have a very, very, very good chance of surviving, of getting through it.

And, in fact, everybody -- the 1,000 people who were in that building, (the) 300 workers and 700 other visitors, have all been on Cipro. And health officials have been quick to point out that no one else is sick. So that's a very, very important key in how the antibiotics are actually working.