What diseases do street rats have? - briefly
Urban rats commonly harbor leptospirosis, hantavirus, salmonellosis, plague, and lymphocytic choriomeningitis virus. These pathogens can reach humans via bites, contaminated urine, feces, or flea vectors.
What diseases do street rats have? - in detail
Urban rats harbor a wide range of pathogens that can affect both the rodents themselves and humans who come into contact with them. The most clinically relevant agents fall into bacterial, viral, parasitic, and fungal categories.
- Leptospira interrogans – spirochete causing leptospirosis. Rats excrete the organism in urine; infection leads to kidney damage, jaundice, and hemorrhagic fever in humans. In rodents, the bacteria persist in renal tubules without obvious illness.
- Salmonella enterica – causes salmonellosis. Fecal shedding spreads the bacterium to food and water sources. In rats, infection may be asymptomatic or produce gastroenteritis; humans develop fever, abdominal cramps, and diarrhea.
- Yersinia pestis – the plague agent. Fleas acquire the bacteria from infected rats and transmit it to other hosts. Rats often survive infection, serving as reservoirs. Human plague presents as bubonic, septicemic, or pneumonic forms, each with high mortality if untreated.
- Streptobacillus moniliformis – responsible for rat‑bite fever. Direct bite or scratch introduces the bacterium, producing fever, rash, and arthralgia. Rats may carry the organism in their oral cavity without disease.
- Hantavirus (e.g., Seoul virus) – transmitted through aerosolized rodent excreta. In rats, infection is typically subclinical; humans develop hemorrhagic fever with renal syndrome, characterized by fever, hypotension, and renal failure.
- Rabies virus – rare in rats but possible through bites from infected carnivores. Infected rodents can transmit the virus via saliva; clinical signs include agitation and paralysis before death.
- Bartonella spp. – cause bartonellosis. Rats serve as reservoirs; fleas and lice act as vectors. Human infection may result in fever, lymphadenopathy, or endocarditis.
- Rickettsia typhi – agent of murine typhus. Fleas transmit the bacterium from rat hosts to humans. Symptoms include fever, headache, and rash; rats carry the organism in their bloodstream without overt disease.
- Toxoplasma gondii – protozoan parasite. Rats become intermediate hosts, developing tissue cysts primarily in muscle and brain. Cats acquire the parasite by consuming infected rats; humans infected through undercooked meat may experience flu‑like illness or severe complications in immunocompromised individuals.
- Giardia lamblia – intestinal protozoan. Rats shed cysts in feces, contaminating water supplies. Infection produces diarrhea and malabsorption in both rats and humans.
- Coccidian parasites (e.g., Eimeria spp.) – cause intestinal inflammation, weight loss, and diarrhea in rats; zoonotic potential is limited but contamination can affect other animals.
- Dermatophytes (e.g., Trichophyton mentagrophytes) – fungal skin infections. Rats develop crusty lesions; humans can acquire ringworm through direct contact.
These pathogens illustrate the public‑health importance of controlling urban rat populations and minimizing exposure to rodent excreta, saliva, and ectoparasites. Effective sanitation, pest‑management programs, and personal protective measures reduce the risk of transmission.