Tularemia
What is Tularemia?
Tularemia is a zoonotic infectious disease mainly transmitted from rabbit or deer, so it is also termed as rabbit fever or deer fly fever. Rate of incidence is low, but fatal in nature. The causative agent of infectious disease is Francisella tularensis.
This gram negative aerobic bacterium mainly affects animals and from infected animals infection is transferred to human via direct contact or by biting of insects which carries germ from infected animals. This infection is contagious in nature and usually accumulated in the lungs, skin, eyes and lymph nodes.
Image 1: Tularemia
Symptoms
There are several types of tularemia and general symptoms of all the forms of tularemia are as follows:
- Sudden onset of fever with high temperature (it may raise up to 1040 F) and feeling of chills – duration of fever may last for several days, but not the high temperature continuously; intervals can be there for a time being but with reoccurrence.
- Headache
- Loss of appetite
- Not feeling well
- Lethargy
- Body ache
- Nausea
- Vomiting
- Cold and cough
- Sore throat
- Pharynx inflammation
- Abdominal discomfort associated with spastic pain
The different forms of tularemia have different specification as mentioned in the following:
- Ulceroglandular: It is characterized by skin ulcer at the affected site where the tularaemia is developed due to tick or deer fly bite or direct contact with infected animals. Gradually the skin ulcer is extended to lymph glands; most usual affected body part is the armpit or groin.
- Glandular: Transmission is same as ulceroglandular tularemia, but it differs with ulceroglandular tularemia in respect of ulcer development.
- Oculoglandular: In this case bacteria enter in the body through eye, mainly during slaughtering the infected animal without maintaining the proper hygiene and affected hand touches the eye. The usual symptom is swelling of eye due to inflammation of the lymph glands present near the front border of the ear.
- Oropharyngeal: The route of entry of the infectious disease is orophyangeal route due to intake of infected foodstuff or drink items including water. The specific symptoms of this type of infection are pharyngitis, tonsillitis, stomatitis, ulceration inside the mouth and enlargement of lymph glands adjacent in the neck.
- Pneumonic: The dangerous form of tularaemia is pneumonic tularaemia. Associated symptoms are chest pain, coughing and breathing difficulty. The route of entrance of infectious bacterium is inhalation of contaminated dust particles. But most commonly when other forms of tularemia are untreated and the bacteria are accumulated in the lungs through the circulation.
Causes
Tularemia is a rare syndrome and incidence rate is not more than 150 cases per annum. Tularemia is a contagious disease caused by Francisella tularensis. The transmission of infection to human being is the main cause of onset of tularaemia.
Image 2: Transmission of Tularemia
- During summer when the predominance of insect bite is high, especially affected tick bites causes transmission of infection from animal to children.
- Hunters usually get affected during winter due to the handling of dead animals.
- Direct contact with affected animals by biting.
- Even domestic animals if infected through insect bites can transmit the bacterium to human.
- Even pet animals like cat if kill any rodents and infected bacterium stacked in their claws then scratching by the pet animal cause bacterium entry into systemic circulation.
- Contaminated food and drinking water ingestion also transmit the disease.
- During specimen handling in laboratory from the sample for clinical analysis F. tularensis is transmitted to laboratory staff. This can happened if the la staff is not maintain the full precautionary measures during sample handling and often the rate of incidence is more for unanticipated sample.
- Inhalation of contaminated duct or during culturing the bacterium in the laboratory causes tularemia.
Treatment
Tularemia is a bacterial infection, the treatment option is antibiotics. The selection of route and class of antibiotics totally depends on disease severity and evidence based medicinal practice.
Aminophylin group of antibiotics
Gentamicin or Sterptomycin is mostly prescribed for hospitalized patients, as the route of drug administration is intramuscular or intra venous. In case of ambulatory patient, they need medical assistance for taking the injection.
Tetracycline group of antibiotics
Long acting tetracycline group of medicine- Doxyclicine is widely prescribed for tularaemia. It can be given orally. The available brands are Oracea, Vibramycin.
Novel Approach
Some patient having hypersensitivity reaction against tetracycline, for those researchers conducted clinical trials by using ciprofloxacin (fluroquinolone group of antibiotics). Clinical trials provide positive approach, but FDA did not approve the drug for preventive measure of tularaemia.
Associated complications treatment
Pneumonia and meningitis are associated complication often found with tularaemia. For treatment as well as for prevention antibiotic therapy is recommended, but success rate is less or recurrence is common.
References
- http://www.mayoclinic.org/diseases-conditions/tularemia/basics/definition/con-20028009
- Tularemia: Practice Essentials, Background, Pathophysiology at http://emedicine.medscape.com/article/230923-overview
- Tularemia: Learn About Symptoms and Treatment at http://www.medicinenet.com/tularemia/article.htm
- http://www.cdc.gov/tularemia/signssymptoms/
- http://www.cdc.gov/Tularemia/