Diseases Spread by African Rats

1. Monkeypox (Mpox)

• Reservoir: Gambian pouched rat (Cricetomys gambianus) and rope squirrel are the main suspected reservoir hosts
• Spread: Contact with infected animals via biological fluids, bites, consumption of bushmeat, or contact with infected humans through droplets/fomites
• Endemic region: Western and Central Africa, especially the Democratic Republic of Congo (first identified in Zaire in 1970)
• Symptoms: Fever, rash clinically similar to smallpox; rarely encephalitis
• Treatment: Supportive care; tecovirimat, cidofovir, and smallpox vaccine offer protection
• (Bradley & Daroff's Neurology in Clinical Practice)

2. Lassa Fever

• Reservoir: The Natal multimammate rat (Mastomys natalensis), endemic to West Africa
• Spread: Contact with rat urine, droppings, or saliva; person-to-person via bodily fluids
• Scale: Estimated 50,000-100,000 cases annually; high human-to-human transmissibility
• Symptoms: Viral hemorrhagic fever - fever, weakness, hemorrhage, multi-organ failure
• Classification: Arenavirus (Old World group)
• (Goldman-Cecil Medicine; Sherris & Ryan's Medical Microbiology)

3. Plague (Yersinia pestis)

• Vector: The Oriental rat flea (Xenopsylla cheopis), which parasitizes rats including African species
• Spread: Flea bites rats, ingests the bacterium, then bites humans; also via urban rat populations in Africa, Asia, and South America
• Forms: Bubonic plague, septicemic plague, pneumonic plague
• (Harrison's Principles of Internal Medicine; Medical Microbiology 9e)

4. Murine Typhus (Rickettsia typhi)

• Vector: Also transmitted by the Oriental rat flea (Xenopsylla cheopis)
• Spread: Flea bites or flea feces contaminating skin/eyes
• Symptoms: Fever, headache, rash
• (Henry's Clinical Diagnosis)

5. Other Zoonotic Diseases Associated with Rats (including African species)

Key Points

• The Gambian giant pouched rat is specifically linked to monkeypox outbreaks, including the 2003 US outbreak traced to imported African rodents
• The multimammate rat is one of the most dangerous rodent disease reservoirs in Africa, serving as the primary host for Lassa virus
• Transmission routes include bites, scratches, urine/feces contamination, flea bites, and bushmeat consumption
• The importation of African rodents as exotic pets has caused international disease outbreaks