Dermatologists never thought we'd find ourselves on the front line of diagnosing bioterrorism; but with 4 of 5 likely bioterrorism threats associated with skin findings, we have gone from dealing with wrinkles to thinking about warfare. Anthrax, smallpox, tularemia, plague and botulism frequently are mentioned as potential threats. I would like to educate you here in this article on anthrax and smallpox, and hopefully dispel some of the hysteria that has developed.

What Is Anthrax?

Anthrax is a bacteria technically a spore-forming bacillus, called Bacillus anthracis. This tiny microscopic organism is usually associated with hoofed animals and the environment they live in. Here in the U.S., the endemic zones tend to follow the old cattle drive regions of the 1800s. This bacillus lives in spore form, sometimes up to 100 years in the soil. It can also live on the animal. Sheep, cattle, goats and camels are the favorite host animals. Man finds himself the unfortunate dead end through accidental infection. It is so unusual to hear of a U.S. infection that until the recent scare, inhalation anthrax last case 1976; last cutaneous case 1992.

What does it look like?

You can't see the bacillus, as it is microscopic. Spores can be mixed in a white or light brown powder for terrorism purposes.

How can I get it?

You have to become infected with the spores by breathing them in (inhalation), eating infected meat (ingestion) or through a break in the skin (cutaneous). Anthrax is NOT contagious meaning you can't catch it from infected people. You can't cough or sneeze Anthrax onto somebody. You can't rub it onto somebody. And it isn't easy to catch Anthrax. The spore has to be a specific size to be able to get itself deep into the lungs (between 1-5 millimicrons). And most of you know by now that between 10 and 15 thousand spores must make it into the lungs to cause inhalation anthrax.

What does cutaneous anthrax look like?

The spores are introduced through a break in the skin; hangnail, paper cut or eczema are all potential sources. You don't need a large wound in order for the spores to infect the skin. However, the spores MUST penetrate the skin; simply touching the spores will not cause infection.

An itchy red bump similar in appearance to a bug bite develops within 1-3 days of skin infection. Soon after that, small blisters appear and the area becomes swollen, dusky red/purple and grows to approximately 3 cm, or the size of a half dollar. There is a gel-like appearance of the swollen area. The center turns black as the skin dies and a sore with a scab forms. The sore is PAINLESS. This is an important distinguishing characteristic from other skin conditions such as a brown recluse spider bite. Lymph nodes that drain the local area may become swollen. The patient may develop a fever, headache or feel generally ill.

What are the symptoms of inhalation anthrax?

There is an average 7-day incubation period after exposure although some cases have developed as late as 60 days out from the initial time of exposure to the spores. A flu-like syndrome accompanies by a dry cough develops and then the infected patient starts to look like they are getting better for a day or 2. The patient then gets worse as the exotoxin made by the bacillus gets into the blood stream. Lowered blood pressure, difficulty breathing and shock occur. There is a mortality rate of 80-100% for untreated inhalation anthrax.

What are the symptoms of ingestion anthrax?

Ingestion anthrax comes from eating infected meat often goat meat, which is normally not seen in the U.S. Symptoms are similar to severe food poisoning with nausea, vomiting, and diarrhea.

How is anthrax treated?

Cutaneous anthrax responds to oral antibiotics including Cipro, Penicillin and Tetracycline. Treatment may be started as late as a few weeks after developing the sore with good results. Without treatment, there is a risk of the bacillus spreading in the blood stream and a 20% mortality rate.

Interestingly enough, all of the literature says that penicillin, usually given intravenously, is the drug of choice for anthrax. The concern has been that there are some lab strains that are penicillin resistant. So we have always thought we would give IV vancomycin instead to cover for this possibility. That is why Cipro is being recommended as the oral choice for the treatment of anthrax as it will cover for penicillin resistant strains. There are other choices for those Cipro allergic patients. For those of you who are stocking up on Cipro: while I don't condone this, unless you plan to take the entire 60 day course of the medication, you aren't going to protect yourself and you may contribute to the development of Cipro resistant strains of anthrax.

Does exposure mean infection?

We've been hearing of more than 30 people at the U.S. Capital alone who were "exposed" to anthrax. All that means is that some spores were found on them, likely from nasal swabs. This absolutely does not mean they were infected. It simply means they were in the vicinity of the spores.

Thousands of people have been tested for anthrax and so far, there are only 12 confirmed cases of infection with 6 of them cutaneous anthrax. I would urge people to realize that it is incredibly unlikely that you will become exposed to anthrax let alone become infected by it. And from what we have seen over the past month is that while it normally should take just 7 days to develop inhalation anthrax or 3 to develop cutaneous anthrax, very few individuals have had problems considering the number of individuals at NBC, CBS, ABC, Capital Hill, Governor Pataki's office, The Sun or the U.S. Post Office. In fact, when I was recently asked if I thought the targeting of high profile personalities with anthrax was meant to instill more fear into the public, I felt the opposite. I actually find it reassuring with each passing day as more people are confirmed exposed that we aren't seeing a larger number of deaths or life threatening forms of infection.

While we are now aware that the anthrax contained within letters that have infected some postal workers and was contained in Tom Daschle's letter was purified and the spores extremely small and obviously capable of causing infection more easily from contact with the letters passing through the post office, the general public remains fairly insulated so far from the threat. Certainly the concern felt by the initial discovery of crop dusting plane plans that could lead to infecting thousands of Americans has not come to reality.

SMALLPOX

What is smallpox?

Smallpox is a disfiguring, potentially lethal blistering virally transmitted infection. An extremely contagious virus, variola was considered eradicated off the face of the Earth in 1977 by the World Health Organization. Smallpox has a 30% rate of mortality and can be passed on from infected individuals. High levels of contagion combined with an unprotected population are why there is such concern that a recurrence of smallpox would be devastating. While similar to chickenpox in many ways, it is dissimilar, too. Both tend to follow the winter and early spring for prime infection time.

Vaccination for smallpox ended in 1972 in the U.S. Anyone who did have the vaccine (look for the tell-tale pockmark scar on your upper arm or thigh) is no longer protected. Without a booster, the vaccine lasts for just 10 years; it's been more than 25 since the last vaccination given in the U.S. Those boosters have not been given hence the lack of protection. Just today someone I spoke with expressed surprise thinking that they received smallpox boosters with their DPT, but this is untrue.

If smallpox is eradicated, where did it come from?

When the WHO declared smallpox eradicated, only 2 known sources of the virus remained in research facilities. One was here in the U.S. at the CDC, one was in Novosibersk, Russia. While there had been a predetermined time to destroy all remaining research material in 2002, the Russians were manufacturing literally tons of the virus and experimenting with how to disperse the virus in bombs. The concern with the collapse of the USSR is that either small amounts of the virus and scientists with the knowledge of how to grow smallpox went to the enemy. The idea of using smallpox for bioterrorism isn't new. It was used in the mid 1700s during the French and Indian war as a method of infecting the Indian tribes. By giving out blankets previously used by infected smallpox patients, more than 50% of infected tribe members succumbed to smallpox.

How can I get it?

Just like many other virally transmitted diseases, smallpox is spread through tiny saliva particles that are sneezed or coughed into the air and then breathed in by an uninfected individual. If smallpox was aerosolized in a bomb, it can last 2 days in the air in particle form. Smallpox does remain on infected clothing and bedding and these items should be autoclaved, burned or destroyed to prevent the further spread of infection. Surfaces need to be cleansed with Lysol, Chlorox or other antiviral agent.

Smallpox vs. Chickenpox

Most people are familiar with chickenpox and unacquainted with how it varies from smallpox. We are coming up on the time of year (early winter through early spring) when chickenpox typically surfaces. To try to alleviate concern if you see blisters, I'd like to compare the 2 infections.

Smallpox is caused by the pox virus, variola.
Chickenpox is caused by the varicella zoster.

Both viruses are spread through the oropharyngeal route, ie. through coughing and sneezing.

The incubation time, or time it takes between exposure and getting sick for smallpox is approximately 12-14 days.
For chickenpox, it's between 14-21 days.

Initially the smallpox patient develops a high fever and headache and becomes quite ill and remains quite ill throughout the course of the infection.
In chickenpox, once the fever has broken and the blisters come out, many patients (particularly children) look pretty well while dealing with their blisters.

What does smallpox look like?

Next in smallpox, innumerable red spots develop primarily on the arms, legs and head with an eventual spread onto the torso.
This is opposite of chickenpox that affects head and torso first. Then blisters develop. Again, there is a significant difference between smallpox and chickenpox.

What are the symptoms of smallpox?

In smallpox, the blisters are all the same age and develop at the same time. They are also painful.
In chickenpox, there are continuous crops of blisters and of course the patient experiences itching.

In smallpox, the blisters are tense and then develop into pustules and then scab.
In chickenpox, the blisters are very fragile and burst easily.

In smallpox, the patient is contagious once the rash develops until the scabs are gone.
In chickenpox, the patient is most contagious before the rash develops and until there is scabbing.

In smallpox, there is significant disfiguring scarring as there is considerable dermal damage from the viral particles.
In chickenpox, while pock marks can occur, they tend to be few and not the norm.

Does exposure mean infection?

As smallpox is so highly contagious, anyone exposed to it is considered at risk. For this reason, VIG (variola immune globulin) and smallpox vaccine will probably be given to anyone known to come into contact with a smallpox patient.

What is the treatment?

Treatment for smallpox is supportive, with fluids and possibly antibiotics to help prevent a secondary bacterial infection. We don't have proven antiviral therapy for smallpox, unlike chickenpox where we might give Acyclovir for severe or at risk patients. Some research exists in animals that an antiviral drug known as Vistide (cidofovir) may help. Don't think however that you can run out and stock up on this drug. It is given intravenously and has a high rate of causing kidney failure. And it is unproven. There are currently 7 million emergency vaccine doses in the U.S. with more stockpiled in other countries. Currently Acambis (formerly OraVax) in Cambridge, Massachusetts has been authorized to make another 40 million doses of the vaccine. Originally these doses were to be ready by 2004, but they are now expected to be available sometime in the summer of 2002. Just today I heard that more than 300 million doses have been ordered, but I have not seen this confirmed. There are problems with the vaccine and these include a low risk of death and brain damage. That is why it has been felt that vaccination around infected cases is best at this time (and of course there aren't enough doses to go around anyway).

I think that the saving grace of smallpox is that is not contagious until the rash has started. This will give authorities some time to track down others exposed to smallpox should this terrifying event ever occur. Vaccination within 4 days of exposure is thought to prevent the development of smallpox.

Again, I want to reassure the public that the current situation with Anthrax is under control and that the risk is so very small right now that we need to concentrate on our overall national security. Wariness is important, but let's not panic. United we stand and we need to stay focused, too.

Photographs courtesy of Infectious Disease expert D. McKinsey, M.D. and G. Lee, M.D. who personally photographed the cutaneous anthrax patients during the anthrax outbreak in Rhodesia 20 years ago. Smallpox photo from CDC. Reproduction of these images is strictly prohibited.

Thank you for taking the time to read through this important information. I hope you have found this article informative.

Audrey Kunin, M.D.

(Any topic discussed in this article is not intended as medical advice. If you have a medical concern, please check with your doctor.)

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