Skip to main content

Rodent-Borne Diseases

The most common and concerning diseases carried by rodents.

Arenavirus

  • Description: A rodent transmitted viral disease. Arenavirus infections are relatively common in humans in some areas of the world (not the United States) and can cause severe illnesses. The arenaviruses are divided into two groups: the New World or Tacaribe complex and the Old World or LCM/Lassa complex.
  • Cause: Disease caused by many types of viruses belonging to the Arenaviridae.
  • Incubation: period varies with the type of viral infection.
  • Symptoms: Varies with the type of viral infection.
  • Diagnosis: By physician.
  • Treatment: Varies with the type of viral infection. Supportive medical care and management of fever is important.
  • 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.

Hantavirus Pulmonary Syndrome

  • Description: A viral disease that may be contracted through direct contact with, or inhalation of, aerosolized infected rodent urine, saliva, or droppings.
  • Cause: Disease caused by a virus found in the saliva, urine and droppings of some species of wild rodents, especially deer mice.
  • Incubation: period 1 to 5 weeks.
  • Symptoms: Fever, severe muscle aches, fatigue. After a few days, difficulty breathing, dizziness, chills, vomiting, diarrhea and stomach pain.
  • Diagnosis: By physician.
  • Treatment: Supportive care by a physician.
  • Mode of Transmission: Contact with mouse urine, droppings and nesting materials. Also by stirring up – or aerosolizing – mouse urine and droppings when cleaning contaminated areas.

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.
  • Incubation: period 4 to 19 days.
  • Symptoms: Fever, headache, chills, severe malaise, vomiting. Occasionally meningitis, rash, jaundice, anemia. Clinical illness can last up to three weeks.
  • Diagnosis: By physician although laboratory tests difficult and not always conclusive.
  • Treatment: With antibiotics.
  • 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.

Lymphocytic Choriomeningitis

  • Description: A viral disease also known as LCM, Benign or Serous Lymphocytic Meningitis.
  • Cause: Disease caused by a virus.
  • Incubation: period 8 to 21 days.
  • Symptoms: Sometimes begins with flu-like symptoms, sometimes begins with inflammation the brain (encephalitis) or both the brain and the membrane that surrounds the brain and spinal cord (meningoencephalomyelitis).
  • Diagnosis: By physician isolating virus from blood or cerebrospinal fluid.
  • Treatment: Supportive care (fluids and management of fever). Most cases make a full recovery.
  • Mode of Transmission: From exposure to infected House Mouse urine, feces and saliva.

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.
  • Incubation: period 1 to 2 weeks.
  • 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.
  • Diagnosis: By physician with lab tests.
  • Treatment: Antibiotics and supportive care.
  • 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.

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.
  • Incubation: period 2 to 6 days.
  • 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.
  • Diagnosis: By physician with lab tests.
  • Treatment: Antibiotics and supportive care.
  • 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.

Rat Bite Fever

  • Description: A bacterial disease that can be contracted from the bite of a rat or mouse. Rat Bite Fever is also known as Streptobacillary Fever or Spirillary Fever.
  • Cause: Streptobacillary fever is caused by the bacterium Streptobacillus moniliformis. Spirillary Fever caused by the bacterium Spirillum minor.
  • Incubation: period 1 to 3 weeks for Spirillary Fever; 3 to 10 days, rarely longer, for Streptobacillary Fever, following a history of a rat or mouse bite, which has normally healed.
  • Symptoms: Abrupt onset of fever, chills, headache and muscle pain. Later followed by a rash which is most pronounced on the extremities. One or more large joints then become red, swollen and painful.
  • Diagnosis: By physician and lab cultures using blood, lymph or joint fluid samples.
  • Treatment: Antibiotics, without treatment fatality rate is 7 – 10%.
  • Mode of Transmission: Usually following a bite from an infected rat or mouse.

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.
  • Incubation: period 6 to 72 hours.
  • Symptoms: Sudden onset of headache, acute abdominal pain, diarrhea, nausea, sometimes vomiting, fever. Potential for dehydration especially in children.
  • Susceptibility: Children are the most susceptible to the virus.
  • Diagnosis: By physician.
  • Treatment: With antibiotics.
  • 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.

For more information about these diseases go to the CDC Diseases from Rodents page.