Rodent Borne Diseases

Monday, 2 February 2009

Rodent Borne Diseases

Plague
Description: A bacterial disease caused by the bites of infected fleas. Can present itself as bubonic plague, pneumonic plague or septicemic plague.
Cause: Disease caused by the bacterium Yersinia pestis.
Symptoms:
Bubonic form: Swollen tender lymph nodes, especially in/near the groin area. Fever usually present.
Pneumonic form: involves above symptoms but disease has progressed and includes the lungs resulting in pneumonia. This form is highly contagious being passed from person to person through droplets of sputum when the infected individual coughs.
Septicemic Form: Plague in blood and being spread to all parts of the body.
Mode of Transmission: From the bites of infected fleas. Various rodents (squirrels, chipmunks, rats, etc.) are the natural reservoir for the bacterium. Fleas of rodents bite humans when sufficient rodent hosts are no longer available.

Arenavirus
Description: A rodent transmitted viral disease. Arenavirus infections are relatively common in humans in some areas of the world and can cause severe illnesses.
Symptoms: Varies with the type of viral infection.
Mode of Transmission: Contact with infected rodent urine, droppings and nesting materials. Also by stirring up - or aerosolizing - rodent urine and droppings when cleaning contaminated areas. By consumption of contaminated food or by direct contact of broken skin with rodent excrement. Wild rodents transmit this disease by contaminating food and drink with their feces and urine.
Salmonellosis
Description: A bacterial food poisoning that may be transmitted when rodents contaminate food by contact with their own feces or urine.
Cause: Disease caused by a Salmonella spp. bacteria, especially Salmonella typhimurium.
Symptoms: Sudden onset of headache, acute abdominal pain, diarrhea, nausea, sometimes vomiting, fever. Potential for dehydration especially in children.
Mode of Transmission: By consumption of contaminated food or water or poorly cooked foods. Domestic pets and wild rodents (rats/mice) can also be carriers of this disease. Wild rodents transmit this disease by contaminating food and drink with their feces and urine.
Leptospirosis
Description: A bacterial disease that may be contracted through contact with water or ingestion of food contaminated with the urine of infected rats and mice. Also known as Weil’s disease, Canicola Fever, Hemorrhagic Jaundice, Mud Fever, Swinehard’s Disease.
Cause: Disease caused by a bacterial spirochete, Leptospira icterohaemorhagiae.
Symptoms: Fever, headache, chills, severe malaise, vomiting. Occasionally meningitis, rash, jaundice, anemia. Clinical illness can last up to three weeks.
Mode of Transmission: Ingestion of contaminated food or water with the urine of rats and mice. Also contact with water, soil and vegetation contaminated with the urine of infected animals.

Murine Typhus
Description: A bacterial disease caused by the bites of infected fleas. Also known as Flea-borne typhus, Endemic typhus fever, Shop typhus.
Cause: Caused by the bacterium Rickettsia typhi.
Symptoms: Headache, chills, fever, general pain; spots/rash appear on the fifth or sixth day on upper body and ultimately spread to all of body except face, palms of hands and soles of feet.
Mode of Transmission: By fleas associated with rats. Rats are the reservoir for the bacterium. Fleas bite both rats and humans. Infection in rats is not apparent.