October 25, 2001

Facts about Anthrax

By Lynn Hinds
MS,OHNP, COHN-S
www.workcare.com

Anthrax is a soil bacterium that forms spores.  It most commonly occurs in wild and domestic animals, cattle, sheep, goats, camels, antelopes and other herbivores.  Anthrax can also occur in humans when they are exposed to infected animals or tissues from infected animals.  We've known about anthrax for a long time.  In fact, anthrax was categorized as one of the first occupational hazards of ancient wool-sorters.  It used to be a common infection in the United States before we began to routinely vaccinate our livestock.  Over the last one hundred years, anthrax in humans has been rare in this country.  The CDC reports just 236 cases of all types between 1955 and 1999.  There have only been 18 confirmed inhalation cases from 1900 to 1976, and not a single case, until now, over the last 25 years.  Typically, the way people get it now is through the handling of animals or soil that contain the bacteria and its spores.  You cannot get the infection from another person.

Human anthrax has three major clinical forms: cutaneous, gastrointestinal, and inhalation.

Cutaneous anthrax.

Most  (95%) of all naturally occurring anthrax infections in humans are cutaneous. Like inhaled anthrax, it is not contagious.

Risk Groups

Occupational risk groups include those coming into contact with livestock or products from livestock, e.g., veterinarians, ranchers, animal handlers and abattoir workers.

Transmission

The source of infection in naturally acquired disease is infected livestock and wild animals or contaminated animal products.

The most common way of getting anthrax is through cuts, blisters, and other breaks in the skin.

Symptoms  

A rash appears within 1-2 days of exposure.  The bumps then turn into fluid filled painless vesicles.  Over the course of several days the vesicles ulcerate and turn black.

Treatment

Antibiotics are extremely effective against naturally occurring strains.  If left untreated 20% of the skin cases of anthrax are fatal.

Gastrointestinal Anthrax

While not very common in the United States , it can occur in small epidemics in Africa and Asia .

Transmission

Gastrointestinal outbreaks follow ingestion of insufficiently cooked contaminated meat.

Symptoms

Eating the meat from infected animals can cause abdominal cramping, nausea and vomiting, fever and severe diarrhea.

Treatment

Antibiotics including penicillin, doxycycline and ciprofloxacin (CiproÒ) are the primary treatment.  About 25-60% of untreated cases result in death.

Inhalation anthrax: 

This is the rarest but deadliest form of Anthrax.

Risk Groups

Inhalation (pulmonary) anthrax occurs in persons working in certain occupations where spores may be forced into the air from contaminated animal products, such as animal hair processing.  You cannot catch it from another person.

Transmission

Anthrax spores that are blown or stirred up into the air can be inhaled.  Aerosolized spores will usually settle quickly. 

Symptoms 

Once introduced into the body, the anthrax spores travel into the tiny air sacs in the lungs.  They spread to the lymph glands and produce toxins, which is what creates the illness in the host.  This incubation period from exposure to onset of illness is usually 1-7 days but may be up to 60 days.  In the first stage of the illness patients can developa spectrum of nonspecific flu-like symptoms, including fever, shortness of breath, cough, headache, vomiting, chills, weakness, abdominal pain, and chest pain.  Then, in hours or in a few days, some patients will have a brief period of recovery.  Others progress directly to the second stage of the disease.  This second stage develops abruptly, with sudden fever, difficulty breathing, sweating, delirium, shock and coma.  In this second stage of illness, death sometimes occurs within hours.

Would I know if I'd inhaled it?

According to Time.com, you would not know if you inhaled it  until the symptoms manifested themselves.  “And this is the challenge, of course, for health professionals, because you need to treat the disease in a very early stage, when the symptoms are still non-specific, flu-like symptoms. It's difficult to diagnose — in order to even test for it you have to suspect this as a possibility or you'll probably overlook it.  Doctors need to be trained to differentiate this from the flu at an early stage.”

Post Exposure Treatment

The primary way for preventing anthrax after known exposure is with antibiotics.  If they are given early enough during the first stage of the infection, it can treat or cure all forms of the illness.

There is an anthrax vaccine for human use, but it's only available in very limited quantities to the military.  It requires six doses over eighteen months with an annual booster in order for it to work.  The vaccination is not recommended for the general public, and the vaccine is not available to health care providers.  The animal vaccine is not suitable for humans.

Preparedness

We all want to be prepared for any type of disaster.  However, these last few weeks have caused us to think about preparing for a new kind of emergency - bioterrorism.  The news media is full of stories about how the public is stocking up with antibiotics in anticipation of a possible bioterrorist attack.  According to Time.com, health care providers are giving the following 5 points of advice to those seeking antibiotics,  ‘just in case'.

1. Do not start taking antibiotics in advance of a suspected attack. To do so would not only exhaust your supply; it would offer no protection against a later attack. If an attack does not come, it is important to consider the expiration date of the antibiotic. After this time, the drug will be useless, and you should throw it out.
2. If you take any antibiotic and feel ill, see your doctor and tell him or her about the medicine you have taken. Like any drug, antibiotics can cause side effects.  For ciprofloxacin, these might include rash, nausea and vomiting, or confusion.
3. Be especially careful if you are taking other medicines. Antibiotics can react with other medications to make them ineffective or even toxic.
4. Do not exceed the normal daily dose of the antibiotic.  More is not better.
5. If you have stockpiled antibiotics for a biological attack, do not use them to self-treat other illnesses. Each antibiotic is useful only for certain types of infections.

In the event of a public health emergency such as a bioterrorist attack, our local and state health departments will inform us about the actions we need to take.  If people need antibiotics after a known or suspected exposure, the federal and state health departments will supply them.