General Information:

Tularemia is caused by the bacteria Francisella tularensis. Normally this disease is transmitted to humans by contact with animals, particularly game animals and by the bites of flies and ticks. Contaminated meat and water are also a source of infection. Francisella tularensis can enter the human body through the skin, mouth, eyes or nose. In biological warfare (BW), it is anticipated that the bacteria would be delivered as a cloud to the target population, making entry through the airways into the lungs the most common route, although ingestion and entry through skin wounds is also possible. The disease may appear as ulcer or lesion at the place of entry and then progress to the lymph nodes and through the blood to other organs, including the lungs if the lungs are not already infected. The fatality rate is about 5-15% if untreated.

Francisella tularensis can remain alive for weeks in water and soil. It is highly infectious in that a very small number of bacteria can cause disease. Disinfection of contaminated articles may be accomplished using a 0.05% hypochlorite solution (1 tbps. bleach per gallon of water).

The military chemical protective mask is effective against inhalation of all Biological Warfare Agents.

Symptoms:

The symptoms of tularemia may vary depending on the method of entry into the body. As stated above, the main route of infection in BW is expected to be inhalation. After 2-10 days, symptoms, such as fever, chills, fatigue, chest discomfort, dry cough and weight loss, would appear. Pneumonia may be evident with a chest X-ray. There may or may not be swollen lymph nodes. The infection may progress from the lungs to the blood and other organs.

If the bacteria enter through a wound on the skin, a skin eruption will usually appear at the sight of entry, but not always. There will most likely be swollen lymph nodes, fever, chills and headache. Pneumonia may also be present. If the bacteria enters through the eye, there will be an inflammation of the lining of the eyelid and associated fever, chills, etc. If the bacteria are ingested the symptoms will be nausea, abdominal pain, vomiting and diarrhea. With antibiotic treatment, tularemia is only fatal in 1-3% of cases.

Medical countermeasures:

Once a person is exposed to tularemia, antibiotics can be given effectively whether or not symptoms have appeared. Streptomycin is the drug of choice; gentamicin and tobramycin are also effective. Antibiotic therapy should be continued until temperature is normal for 4-5 days. As stated above, recovery is expected in all but 1-3% of cases. Human to human spread of the disease is rare, so those infected do not need to be isolated. However, where skin ulcers are apparent, these should be treated with hospital wound secretion precautions.