Anthrax is a serious illness caused by a spore-forming bacterium, Bacillus anthracis. Although anthrax affects mainly livestock and wild game, humans can become infected through direct or indirect contact with sick animals. Normally, anthrax isn't transmitted from person to person, but in rare cases, anthrax skin lesions may be contagious.
Most often, anthrax bacteria enter your body through a wound in your skin. You can also become infected by eating contaminated meat or inhaling the spores. Symptoms, which depend on the way you're infected, can range from skin sores to nausea and vomiting or shock.
Prompt treatment with antibiotics can cure most anthrax infections contracted through the skin or contaminated meat. Inhaled anthrax is more difficult to treat and can be fatal.

What causes anthrax?

The agent of anthrax is a bacterium called Bacillus anthracis. While other investigators discovered the anthrax bacillus, it was a German physician and scientist, Dr. Robert Koch, who proved that the anthrax bacterium was the cause of a disease that affected farm animals in his community. Under the microscope, the bacteria look like large rods. However, in the soil, where they live, anthrax organisms exist in a dormant form called spores. These spores are very hardy and difficult to destroy. The spores have been known to survive in the soil for as long as 48 years.


What Sign And Symptoms anthrax?
There are three types of anthrax, each with different signs and symptoms. In most cases, symptoms develop within seven days of exposure to the bacteria.
Cutaneous anthrax
This form of anthrax enters your body through a cut or other sore on your skin. It's by far the most common form of the disease. It's also the mildest — with appropriate treatment, cutaneous anthrax is seldom fatal. Symptoms of cutaneous anthrax include:

• A raised, itchy bump resembling an insect bite that quickly develops into a painless sore with a black center
• Swelling in the sore and nearby lymph glands

Gastrointestinal anthrax
You contract this form of anthrax by eating undercooked meat from an infected animal. Signs and symptoms include:

• Nausea
• Vomiting, which is often bloody in the later stages of the disease
• Loss of appetite
• Fever
• Severe, bloody diarrhea in the later stages of the disease
• Sore throat and difficulty swallowing
• Swollen neck

Inhalation (pulmonary) anthrax
Inhalation anthrax develops when you breathe in anthrax spores. It's the most deadly form of the disease and even with treatment is often fatal. Initial signs and symptoms of inhalation anthrax include:

• Flu-like symptoms, such as sore throat, mild fever, fatigue and muscle aches, which may last a few hours or days
• Mild chest discomfort

As the disease progresses, you may experience:

• High fever
• Trouble breathing
• Shock
• Meningitis — a potentially life-threatening inflammation of the brain and spinal cord

When to seek medical advice
Many common illnesses start with symptoms that resemble the flu. Anthrax is rare in the developed world, and the chances that your sore throat and aching muscles are due to anthrax are extremely small.
If you think you may have been exposed — for example, if you work in an environment where anthrax is likely to occur — see a doctor immediately for evaluation and care. If you develop signs and symptoms of the disorder after exposure to animals or animal products in parts of the world where anthrax is common, seek prompt medical attention. Early diagnosis and treatment are crucial.

Types of Anthrax

The three main types of anthrax are:

1. Cutaneous or skin anthrax, can occur if someone with a cut or scrape handles contaminated animals or animal products. More than 95% of anthrax cases are of the cutaneous type, which is the least dangerous form. A person with cutaneous anthrax will notice a small sore that develops into a painless ulcer with a black area in its center. If left untreated, the infection can spread to other areas of the body.
2. Intestinal anthrax can occur if someone eats undercooked contaminated meat. Intestinal anthrax is far less common than cutaneous anthrax, but it can make someone much sicker. Intestinal anthrax symptoms include severe abdominal pain, nausea, vomiting, severe diarrhea, and bleeding from the digestive tract.
3. Pulmonary, or inhaled, anthrax is the rarest form of anthrax — but it's also the most dangerous. Pulmonary anthrax can only occur if someone breathes thousands of anthrax spores into the lungs. Pulmonary anthrax usually seems like a common cold or the flu at first, but it rapidly turns into severe pneumonia and requires hospitalization.

It usually takes fewer than 7 days for a person to show signs of anthrax after being infected. However, symptoms of pulmonary anthrax can sometimes take months to appear.

How Is Anthrax Diagnosed and Treated?

Medical professionals can diagnose anthrax by taking samples from the skin sores, blood, or other bodily fluids of people who are believed to have been exposed to B. anthracis. These samples are then sent to a lab to check whether the person has the bacteria in his or her system.
If anthrax is caught early, it is almost always successfully treated with antibiotics. If a person is known to have been exposed to B. anthracis but has no signs or symptoms of the disease, antibiotics may be given (after exposure) to prevent the disease from occurring.
Although there is a vaccine for anthrax, in the United States it is currently only recommended for people who are at risk of coming into contact with B. anthracis. They include people who work with B. anthracis in laboratories, people who handle potentially infected animal products, and U.S. military personnel. The vaccine is not given routinely to people in the United States and it hasn't been studied for use in people younger than 18.
If you worry when you hear about anthrax, remember that it's very rare, and it's unlikely that you will ever be exposed to the germs that cause anthrax. If you're worried about it, talk to a science teacher or medical professional — someone who can help you find the answers to any questions you may have about anthrax.

How common is anthrax?

Anthrax is now rare in humans in the United States and developed countries. It still occurs today, largely in countries lacking public-health regulations that prevent exposure to infected goats, cattle, sheep, and horses and their products. In the last few years, there have been rare cases of anthrax in people exposed to imported animal hides used to make drums. Drum players, drum makers, and their family members have been infected in this way. The major concern for those of us in western countries (who don't play drums) is the use of anthrax as an agent of biological warfare.

Treatments and Pharmacology

The standard treatment for anthrax is a 60-day course of an antibiotic, such as ciprofloxacin or doxycycline. Which antibiotic or combination of antibiotics will be most effective for you depends on the type of anthrax you have, your age, overall health and other factors. Treatment is most effective when started as soon as possible.
Although some cases of anthrax respond to antibiotics, advanced inhalation anthrax may not. By the later stages of the disease, the bacteria have often produced more toxins than drugs can eliminate.

 

How can anthrax be prevented?

Public-health measures to prevent contact with infected animals are invaluable. There is a vaccine available for people at high risk (such as veterinarians, laboratory technicians, employees of textile mills processing imported goat hair, and members of the armed forces). The Department of Defense and the U.S. Centers for Disease Control and Prevention are working very hard to prevent a bioterrorist attack and to be prepared to deal with the consequences if one occurs. For anthrax and other infectious diseases, vaccines with greater efficacy and fewer side effects are under development. Currently, most vaccines are given by injection into fat or muscle below the skin. Early studies in experimental animals are showing promise for an oral vaccine for anthrax. Obviously, a pill is easier to take than a shot, and the pill may even be a safer and more effective route of administration.

Sources

1. Anthrax. Centers for Disease Control and Prevention. http://www.cdc.gov/nczved/dfbmd/disease_listing/anthrax_gi.html. Accessed March 23, 2009.
2. Anthrax Q & A: Anthrax & influenza. Centers for Disease Control and Prevention. http://emergency.cdc.gov/agent/anthrax/faq/flu.asp. Accessed March 23, 2009.
3. Anthrax Q & A: Vaccination. Centers for Disease Control and Prevention. http://emergency.cdc.gov/agent/anthrax/faq/vaccination.asp. Accessed March 23, 2009.
4. Shadomy SV, et al. Clinical manifestations and diagnosis of anthrax. http://www.uptodate.com/home/index.html. Accessed March 23, 2009.
5. Shadomy SV, et al. Treatment and prevention of anthrax. http://uptodate.com/home/index.html. Accessed March 23, 2009.
6. Anthrax Q & A: Diagnosis. Centers for Disease Control and Prevention. http://www.bt.cdc.gov/agent/anthrax/faq/diagnosis.asp. Accessed March 23, 2009.
7. Anthrax. U.S. Food and Drug Administration. http://www.fda.gov/cber/vaccine/anthrax.htm. Accessed March 23, 2009.