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Rats are responsible for spreading many infectious diseases, some of which can cause severe health risks for humans. They can be carriers of bacteria, viruses, and parasites that are easily spread through contact with contaminated materials, bites, or exposure to ectoparasites like fleas, mites, and ticks. This guide examines the health risks associated with rat infestations, explains how diseases spread from rats to humans, and outlines preventative steps to help keep your home protected.
Rat infestations pose numerous public health concerns as these rodents are known to carry a range of harmful pathogens. Understanding the health risks associated with rats and the common diseases they transmit can help you stay informed and take preventive measures. If you are experiencing a rat infestation, contact us at Ehrlich for our professional rat extermination service.
Rats can be carriers of various diseases and pathogens that can infect humans, particularly when infestations lead to increased exposure to their feces, urine, saliva, or nesting materials. Because rats live in close quarters with humans in urban and suburban settings, the risk of disease transmission is relatively high. Moreover, they are often infested with ectoparasites such as fleas, mites, and ticks, which can also carry and spread diseases.
Rats can spread diseases to humans through direct contact, indirect exposure, and via ectoparasites. Direct transmission occurs through contact with infected rodent droppings, urine, saliva, or bites, whereas indirect transmission happens when fleas, ticks, or mites feed on an infected rat and later bite a human, passing the disease along in the process. Rats also gnaw and contaminate food, surfaces, and personal items, making the risk of infection significant if they’re left unchecked.
Diseases carried by rats can spread to humans in several ways. Understanding these transmission routes is key to preventing exposure.
Direct contact with rat droppings, urine, saliva, or even handling the rats themselves can potentially expose people to diseases. Any handling of contaminated materials without proper protection should be avoided as it can lead to bacterial or viral infection. Although uncommon, rat bites are also a direct transmission method and can happen when rats feel cornered or threatened.
Ectoparasites like fleas, mites, and ticks, which live on rats, are indirect carriers of rat-borne diseases. When these parasites bite a human after feeding on an infected rodent, they can transmit the disease. (Rats have historically been blamed for spreading the parasites that transmitted bubonic plague in the past, but a recent study suggests that human parasites may have been a more likely source of transmission). Ticks and mites on rats can also spread various diseases to humans, posing ongoing health risks in areas with rodent infestations.
Rat droppings, urine, saliva, and nesting materials are major sources of contamination. Inhaling dust from dried feces or urine, handling nesting material, or unknowingly coming into contact with contaminated surfaces can lead to infection. Hantavirus and leptospirosis, for instance, are diseases often spread through contact with rat urine or droppings.
Rats can carry several infectious diseases that can be transmitted to humans, potentially leading to severe health consequences. Here are some of the most significant diseases spread by these pests:
Leptospirosis is a bacterial infection that humans can contract through contact with contaminated rat urine or water. This disease can cause symptoms such as fever, muscle aches, and jaundice and can lead to kidney or liver failure if untreated. It’s commonly spread in areas with standing water, as the bacteria can survive in moist environments.
In the United States, hantavirus infections are primarily associated with different rodent hosts and result in varying strains of the virus. For instance, the Seoul virus, associated with the Norway rat and roof rat, can cause Hemorrhagic Fever with Renal Syndrome (HFRS) rather than the HPS associated with deer mice. Because hantavirus particles can become airborne, the risk of infection is particularly high in enclosed spaces where rodent droppings have dried out.
Rats can carry Salmonella bacteria, which can contaminate food sources and surfaces. Humans contract salmonellosis by ingesting contaminated food or water. Symptoms of salmonellosis include diarrhea, vomiting, fever, and abdominal cramps. Proper food storage and hygiene are essential to prevent salmonella contamination in areas where rodents are present.
Caused by the bacterium Yersinia pestis, plague is transmitted by fleas that have fed on infected rodents or other wildlife. Bubonic plague, in particular, is a severe disease that causes swollen lymph nodes, fever, and other flu-like symptoms. Although rare today (an average of seven cases per year are reported in the United States according to the CDC), plague outbreaks still occur and can be fatal if not treated promptly.
Rat-bite fever (RBF) is caused by bacteria that live in rats’ saliva and can be transmitted to humans through bites or scratches. Symptoms include fever, vomiting, muscle pain, and rash. Rat-bite fever can be serious if untreated, with potential complications affecting the heart, brain, and lungs.
LCMV is a viral infection that humans can contract from exposure to rat urine, droppings, or saliva. Most people experience no symptoms or only mild flu-like symptoms, but some people can experience more severe symptoms, including meningitis or encephalitis. Pregnant women should be especially cautious, as LCMV can pose risks to the fetus if contracted during pregnancy.
Preventing exposure to rat-borne diseases requires a proactive approach. Here are several measures to help reduce the risk of infection and prevent rat infestations.
Good sanitation practices can discourage rats from entering your home. Clean up food scraps, store food in airtight containers, and dispose of garbage properly. Regularly clean and disinfect surfaces to minimize contamination risk, especially in areas where rats are present.
Rats can enter buildings through tiny openings. Inspect your home for gaps, cracks, or holes that rodents might use to gain entry, and seal these points with durable materials like steel wool or caulking. This simple preventive measure can go a long way in keeping rats out.
Routine pest control treatments and inspections can help you detect and prevent infestations before they become serious. If you have a persistent rodent problem, consider hiring a professional pest control service like Ehrlich to effectively remove the rodents and treat your property to reduce future risks.
NB: You should always wear proper protective equipment (PPE) when entering an area with a suspected rodent infestation. This generally includes an N95 mask, gloves, and goggles. You should also ensure that airborne contaminants are not dispersed to surrounding areas. For more information, see our article on how to clean after a rodent infestation.
If you’re concerned about the health risks associated with rat infestations, Ehrlich pest control can provide effective solutions to remove rats and prevent future infestations. We can identify entry points, remove rodent droppings, and sanitize contaminated areas, ensuring a protected environment for you and your family.
For more information about rats, see our articles on common rats in the US, signs of rats in your property and how to get rid of rats.
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