Anthrax is a serious disease caused by Bacillus anthracis, a bacterium that forms spores. A bacterium is a very small organism made up of one cell. Many bacteria can cause disease. A spore is a cell that is dormant (asleep) but may come to life with the right conditions.There are three types of anthrax:
- skin (cutaneous)
- lungs (inhalation)
- digestive (gastrointestinal)
Anthrax is not known to spread from one person to another.
Anthrax from animals. Humans can become infected with anthrax by handling products from infected animals or by breathing in anthrax spores from infected animal products (like wool, for example). People also can become infected with gastrointestinal anthrax by eating undercooked meat from infected animals.
Anthrax as a weapon. Anthrax also can be used as a weapon. This happened in the United States in 2001. Anthrax was deliberately spread through the postal system by sending letters with powder containing anthrax. This caused 22 cases of anthrax infection.
The symptoms (warning signs) of anthrax are different depending on the type of the disease:
- Cutaneous: The first symptom is a small sore that develops into a blister. The blister then develops into a skin ulcer with a black area in the center. The sore, blister and ulcer do not hurt.
- Gastrointestinal: The first symptoms are nausea, loss of appetite, bloody diarrhea, and fever, followed by bad stomach pain.
- Inhalation: The first symptoms of inhalation anthrax are like cold or flu symptoms and can include a sore throat, mild fever and muscle aches. Later symptoms include cough, chest discomfort, shortness of breath, tiredness and muscle aches. (Caution: Do not assume that just because a person has cold or flu symptoms that they have inhalation anthrax.)
- Nasal swab testing may be conducted on several people to detect contamination by anthrax in the environment, but this does not confirm infection by anthrax in an individual.
- Testing to confirm disease in an individual includes blood, tissue, and spinal fluid cultures (before antibiotics); polymerase chain reaction testing; and x-ray to identify mediastinal widening in inhalation anthrax.
- Antibiotic prophylaxis after exposure to spores is warranted, and 60 days therapy is advised. Drug recommendations include:
- Ciprofloxacin 500 mg bid for adults: 10 to 15 mg/kg bid for children.
- Doxycycline 100 mg bid for those weighing 99 pounds (45kg) and over; 2.2 mg/kg bid for children at least age 8 but weighing 99 pounds or less.
- Amoxicillin 500 mg bid for adults; 80 mg/kg divided into three doses for children (if penicillin sensitivity of organism is confirmed).
- Treatment of cutaneous anthrax involves 60 days treatment using antibiotics, however, signs of systemic involvement, including lesions of the head and neck and extensive edema, require I.V. treatment with multiple drugs as for inhalation anthrax.
- I.V. corticosteroids may be given to adjunct therapy in severe cases.
- Symptomatic treatment includes analgesics, antiemetics, and emergency drugs for circulatory collapse.
- An anthrax vaccine has been available for veterinarians (not routinely used due to low incidence of animal disease).
- Antrax meningitis – is the intense inflammation of the meninges of the brain and spinal cord.
- This is marked by elevated CSF pressure pressure with bloody CSF followed by rapid loss of consciousness and death.
- The case fatality rate is almost 100 percent.
- Anthrax sepsis – develops after the lymphohematogenous spread of B. anthracis from primary lesion.
- Monitor vital signs and hemodynamic parameters closely for circulatory collapse.
- Monitor temperature for response to antibiotic therapy.
- Auscultate chest for crackles, indicating need for better secretion mobilization.
- Monitor oxygen saturation and arterial blood gases periodically to determine oxygenation status and acid-base balance.
- Monitor level of consciousness and for meningeal signs such as nuchial rigidity.
- Provide supplemental oxygen or mechanical ventilation, as needed.
- Position for maximum chest expansion and reposition frequently to mobilize secretions.
- Suction frequently and provide chest physiotherapy to clear airways, prevent atelectasis, and maximize oxygen therapy.
- Administer I.V. fluids to encourage oral fluid intake to replace the fluid lost through hyperthermia and tachypnea.
- For G.I. anthrax, maintain G.I decompression, monitor emesis and liquid stool output, and medicate for abdominal pain, as needed.
- Advice the patient and family that anthrax is not transmitted person to person; one must come in contact with the spores to contact infection.