ANTHRAX Q & A

October 2001

What causes anthrax?

Anthrax is caused by a bacterium (not a virus). More specifically, it's a rod-shaped bacterium that stains purple in a laboratory test.

Where are the bacteria found?

The bacteria live in and on infected animals, and in the soil. The bacteria can't survive long in the environment when they're in a growth stage. But when they form spores -- which they do when the environment changes (for example, when they run out of food) -- they can live in the soil for decades.

How do people get infected?

There are three forms of anthrax: inhalation (where the bacteria lodge deep in the lungs), cutaneous (skin), and intestinal. By far the most common form is cutaneous (about 95 percent of cases).

- Inhalation anthrax comes from inhaling spores of anthrax bacteria. Spores work their way deep into the lungs, and are picked up by immune cells that carry them to lymph nodes, where they multiply and release poisons that cause hemorrhaging and other problems. Not all spores can set up an infection; they have to be small enough to work their way deep into the lungs. Also, 2,500 to 55,000 spores are needed to establish infection.

- Cutaneous anthrax occurs when anthrax bacteria are transmitted to humans from contaminated meat, wool or hides. They enter the skin, usually through cuts and abrasions; 95 percent of anthrax cases are cutaneous.

- Gastrointestinal anthrax comes from ingestion of contaminated, undercooked meat.

Is anthrax easy to catch and spread?

Anthrax is not easy to catch: Years ago, researchers tested workers in a goat-hair mill in Pennsylvania and found that workers regularly inhaled low concentrations of anthrax spores, yet didn't get sick. And it's important to note: People do not transmit anthrax from one to another. It is not contagious.

What are the symptoms?

- Inhalation: Initially, flu-like symptoms Ñ aches, pains, fever Ñ developing into severe breathing problems, shock and death. It's not the same as cold symptoms; colds are marked by runny noses, and a runny nose is not one of the symptoms of anthrax.

- Cutaneous: raised itchy bumps that develop into ulcers with a black area in the center (hence the name anthrax, from the Greek anthrakis, meaning coal).

- Gastrointestinal: nausea, lose of appetite, vomiting, fever, abdominal pain, vomiting blood, diarrhea.

How long after exposure do symptoms appear?

There's some debate about this. The Centers for Disease Control and Prevention in Atlanta says within seven days. In an accidental exposure incident in the Soviet Union in 1979, cases occurred anywhere from two to 43 days after exposure. CDC's treatment recommendation is based on a possible 60-day window.

Recommendations for post-exposure chemoprophylaxis Anthrax usually is susceptible to penicillin, doxycycline, and fluoroquinolones.

--Adult males & non-pregnant females (ages 18-65 yrs):

Ciprofloxacin 500 mg orally twice a day for 60 days OR Doxycycline 100 mg orally twice a day for 60 days OR Amoxicillin 500 mg orally 3 times a day for 60 days

--Pregnant adult females: Amoxicillin 500 mg orally 3 times a day for 60 days

Adults age 65 yrs & over:Doxycycline 100 mg orally twice a day for 60 days

OR Ciprofloxacin 500 mg orally twice a day for 60 days

OR Amoxicillin 500 mg orally 3 times a day for 60 days

--Children 9 yrs & over:

Amoxicillin 500 mg orally 3 times a day for 60 days OR Ciprofloxacin 500 mg orally twice a day for 60 days OR Doxycycline 100 mg orally twice a day for 60 days

--Children less than 9 yrs Amoxicillin 80 mg/kg/day orally, divided into 3 doses a day for 60 days OR Ciprofloxacin 10-15 mg/kg/day orally, divided into 2 doses a day for 60 days OR Doxycycline 5 mg/kg/day orally, divided into 2 doses a day for 60 days

--Drug-drug interactions and individual patient allergies should be considered when selecting an antibiotic for prophylaxis. Amoxicillin is preferred for children. If allergic to Amoxicillin or Penicillin, Ciprofloxacin or Doxycycline may be indicated. In older adults, the potential CNS side effects of Ciprofloxacin should also be considered when selecting an antibiotic for prophylaxis

How to handle anthrax and other biological agent threats DO NOT PANIC

a) Suspicious Unopened letter or package marked with threatening message such as "anthrax":

1. Do not shake or empty the contents of any suspicious envelope or package.

2. PLACE the envelope or package in a plastic bag or some other type of container to prevent leakage of contents.

3. If you do not have any container, then COVER the envelope or package with anything (e.g., clothing, paper, trash can, etc.) and do not remove this cover.

4. Then LEAVE the room and CLOSE the door, or section off the area to prevent others from entering (i.e., keep others away).

5. WASH your hands with soap and water to prevent spreading any powder to your face.

6. Notify your superior or QHSE Officer.

7. LIST all people who were in the room or area when this suspicious letter or package was recognized. This is for follow-up investigations and advice.

b) Envelope with powder and powder spills out onto surface:

1. DO NOT try to CLEAN UP the powder. COVER the spilled contents immediately with anything (e.g., clothing, paper, trash can, etc.) and do not remove this cover!

2. Then LEAVE the room and CLOSE the door, or section off the area to prevent others from entering (i.e., keep others away).

3. WASH your hands with soap and water to prevent spreading any powder to your face.

4. Notify available supervisor or QHSE Officer.

5. REMOVE heavily contaminated clothing as soon as possible and place in a plastic bag or some other container that can be sealed. This clothing bag should be given to the emergency responders for proper handling.

6. SHOWER with soap and water as soon as possible. Do Not Use Bleach Or

7. Other Disinfectant On Your Skin.

8. If possible, list all people who were in the room or area, especially those who had actual contact with the powder so that proper instructions can be given for medical follow-up, and for further investigation.

Vaccination

The vaccine is prepared from a formalin-treated culture supernatant of a nonvirulent B. anthracis strain. It is given in a pre-exposure regimen at 0, 2, and 4 weeks, and at 6, 12, and 18 months. Persons at continuing risk for exposure should receive yearly boosters. Exposed persons should receive at least three doses (at 0, 2, and 4 weeks), assuming no further exposure is likely, before discontinuing chemoprophylaxis.

Decontamination

In certain cases, such as exposure to a threat letter involving an unidentified substance, where anthrax cannot readily be ruled out by Gram stain or other rapid diagnostic procedures, decontamination may be warranted.

Remove all clothing, seal in a plastic bag, and shower with copious amounts of soap and water. Environmental surfaces and personal effects may be treated with 0.5% sodium hypochlorite (household bleach) after the area in which the agent was released is investigated.

How long does diagnosis take?

A variety of testing procedures are available; therefore, the time it takes to determine whether a person has been exposed to anthrax is variable.

According to an article in the Journal of the American Medical Association, a blood culture takes six to 24 hours, and will tell whether there's a general overgrowth of bacteria. Then technicians can do a "Gram test" where they apply special stains that highlight bacteria. A Gram stain takes 10 to 15 minutes, and will identify if the bacteria are in the same category as the bacteria that cause anthrax. Biochemical testing that is specific to anthrax bacteria will take another 12 to 24 hours. The process can be shorter if anthrax is suspected.

Sources: CDC and NPR