Rodents aren’t just a nuisance. They can contaminate air, food and water with serious, life threatening diseases. Sometimes they bring in other disease-carriers like ticks, fleas, and mites into your home. In either case, they represent a threat to you and your family. Here are 25 diseases that rodents can cause.

It is important to remember that many of these diseases have a latency period of 1 to 2 weeks after infection. You should always keep an eye on your health and if you become sick and have an infestation of rodents, consult a medical professional.

1. Hantavirus Pulmonary Syndrome

Rodent feces can contaminate the air around it through dust particles, which can lead to any number of infections. Hantavirus Pulmonary Syndrome is one such disease.

Early signs include fatigue, fever, and muscle aches, and half of all patients report gastrointestinal symptoms and headaches. As the disease progresses, it causes a serious respiratory infection that could result in death.

2. Hemorrhagic Fever with Renal Syndrome

Another illness caused by fecal matter in the air, although this disease is more common in Europe, Russia, and parts of Asia.

The disease is marked first by intense headaches, fever, chills, nausea, and blurred vision. Later symptoms include acute shock, vascular leakage, and acute kidney failure. The disease can be fatal, and nonfatal cases might require months of medical care to fully recover.

3. Lassa Fever

Lassa Fever is often spread through aerated droppings or by accidentally consuming contaminated food and water. However, it can be spread via person to person contact. While this disease is almost entirely based in West Africa, it is not unknown in the U.S.

In most cases, Lassa Fever only presents as a flu-like disease with fever, feelings of weakness, and a headache. However, 1 in 5 cases will suffer more serious symptoms such as hemorrhaging from the eyes, nose, or gums, respiratory distress, vomiting, facial swelling, and tremors.

Lassa Fever is deadly in 1% of all cases.

4. Leptospirosis/Weil’s Disease

Leptospirosis is an international disease spread through food and water contaminated by rodent urine. Even contact with contaminated soil has resulted in infection.

Leptospirosis can be difficult to detect, as it is linked to a wide range of symptoms and some may not experience any symptoms at all. It can be easily mistaken for the flu or another kind of disease. However, if left untreated, it can result in kidney failure, liver failure, and meningitis. These complications can be fatal or may take several weeks to recover from.

5. Lymphocytic Choriomeningitis (LCM)

LCM is seen worldwide and is usually caused by contamination through rodent droppings. Usually, the disease is caused by the common house mouse, but other rodents exposed to the disease may become carriers.

The disease resembles a common flu at first, with headaches, fever, malaise, aches, and vomiting all being reported. However, the disease can also lead to meningitis (often marked by a stiff neck) or more severe neurological symptoms like brain inflammation and increased fluid in the brain.

The disease is typically not fatal, but it can require surgery and may result in brain damage.

6. Omsk Hemorrhagic Fever

As its name implies, this illness is far more common in Western Siberia than it is here. The disease is transferred from rodents to humans through ticks or through direct contact.

Chills, fever, headaches, severe muscle pain, and vomiting are all common symptoms of Omsk Hemorrhagic Fever. More serious symptoms include gastrointestinal issues and bleeding problems.

The disease is rarely fatal, and most patients recover after a few weeks. Some patients may experience a relapse of symptoms in addition to brain inflammation.

7. The Plague

The Plague ravaged the Western world in medieval times. Modern medicine has reduced the deadliness of the disease significantly, but it can still be a serious threat. It can be passed through fleas from infected rodents or through the rodents themselves.

There are many kinds of Plague with different symptoms. The Bubonic Plague is arguably the most well-known form of this disease and is characterized by fevers, headaches, chills, weakness, and swollen lymph nodes. If left untreated, the bacteria can spread throughout the body, leading to complications and death.

8. Rat Bite Fever

Surprisingly, Rat Bite Fever is in fact two diseases primarily passed through rodent bites and scratches—both a bacterial and a viral infection. Handling infected animals also creates a risk of infection.

The bacterial Rat Bite Fever causes fever, vomiting, and headaches. It may also cause a distinctive rash on the hands and feet, and joint pain. The viral version causes an ulcer at the infection site, swelling near the wound, swollen lymph nodes, and a fever. If left untreated, RBF can be deadly.

9. Haverhill Fever

This is actually caused by the same bacteria or virus as Rat Bite Fever, but instead of transmission through a bite, it is consumed through contaminated food and water. Because of the difference in transmission, the symptoms of Haverhill Fever involve more sore throats and severe vomiting than typical RBF. As with all variants of RBF, untreated Haverhill Fever can be fatal.

10. Salmonellosis

Salmonellosis refers to an infection caused by the salmonella bacteria. While it is well-known to be caused by undercooked meat and eggs, rat and mice feces can also contaminate food with the disease.

Infected people often suffer from diarrhea, fever, and abdominal cramps for up to a week. Most individuals will be able to fight the disease on their own, but more severe cases might require medical care and antibiotics to avoid serious complications.

11. Tularemia

Tularemia occurs worldwide, and can be transmitted by handling rodent carcasses, being bitten by infected ticks or deerflies, eating contaminated food, or even breathing in the bacteria.

Tularemia’s symptoms are dependent on how the disease entered the body. If the bacteria was inhaled, it can lead to chest pain, coughing, and difficulty breathing. If it came from a tick, it will manifest as an ulcer at the site of the bite and swollen lymph nodes. The disease is treatable with antibiotics, but can be fatal without medical help.

12. Babesiosis

Babesiosis is caused by parasites spread by ticks. In turn, those ticks are often carried by mice and rats, most often in the northern parts of the United States.

Most cases result in nothing more than some flu-like symptoms or even no symptoms at all. However, the parasite destroys red blood cells, which can lead to anemia and jaundice. It also poses a more serious threat to those with weakened immune systems and those without a spleen, the complications for whom can lead to death.

13. Colorado Tick Fever

Almost a mirror reflection of Babesiosis, Colorado Tick Fever is more prevalent in the western states and is caused by a tick-borne virus rather than a parasite. Rodents tend to help ticks spread the virus by carrying it asymptomatically.

Like many rodent-related diseases, CTF looks the like the flu from the outside, with headaches, fever, chills, body aches, and tiredness as common symptoms. Some patients may suffer vomiting, sore throat, or a rash. Half of all patients have a recurring fever, which fades away for a period only to return again. The disease is rarely fatal, but may take weeks to recover.

14. Cutaneous Leishmaniasis

Cutaneous is most common form of leishmaniasis, a group of parasitic diseases found throughout the world. The parasites are usually spread by sandflies after having bitten infected rodents and dogs.

Cutaneous leishmaniasis causes skin sores, often at the site of the bite, which might change in appearance or size over time. It may also cause lymph swelling.

15. Human Granulocytic Anaplasmosis

This tick-borne bacterial disease is common throughout much of the U.S. thanks to the white-footed mouse, large numbers of which carry the disease. It is common for patients not to remember even being bitten, as the carrier ticks are miniscule.

The disease manifests differently for everyone, with symptoms ranging from fevers, headaches, chills, rashes, coughing, and confusion. The disease can be fatal if not treated, as it can cause neurological, renal, and respiratory problems in the long term.

16. La Crosse Encephalitis

Infected rodents in southeastern and midwestern states pass this disease to mosquitos, who in turn bite and infect humans. The disease is caused by the La Crosse virus.

Many people infected with the virus display no symptoms, while others develop fevers, headaches, nausea, vomiting, and fatigue. However, more serious cases might involve brain inflammation, which could lead to seizures and permanent brain damage. The disease is rarely fatal.

17. Lyme Disease

Lyme Disease is one of most well-known tick-borne diseases, and is a bacterial infection that has been found throughout the United States. Once again, the white-footed mouse is to blame for acting as a reservoir for the disease.

Lyme Disease’s most famous symptom is the bullseye shaped rash around the bite, although it does not appear in every case. Other symptoms include severe headaches, neck stiffness, more rashes appearing on the body, arthritis, facial palsy, and heart palpitations. If left untreated, nerve pain, inflammation of the brain and spinal cord, and short-term memory loss could result.

18. Murine Typhus

Murine Typhus is a type of typhus fever transmitted largely through rodents’ fleas in warmer parts of the U.S.

Typhus typically causes fevers, headaches, malaise, rashes, and vomiting. All forms of typhus can be deadly if not treated promptly.

19. Powassan Virus

The Powassan Virus is a less famous but no less serious tick-borne illness maintained by infected rodents, including the white-footed mouse. It is most common in the northeast and the Great Lakes region.

About 10% of all cases of Powassan Virus are fatal. The symptoms include fever, headache, vomiting, confusion, loss of coordination, seizures, and speech difficulties. About half of all patients report permanent brain damage.

20. Scrub Typhus

This branch of typhus isn’t generally seen in the United States, more commonly found on the coast of Russia, China, North Australia, and Indonesia. Mites from diseased rodents are the source of this infection.

Scrub typhus may be deadly for between 20 and 60% of all untreated cases. Symptoms include fever, headache, and muscle pain, with coughing, swollen lymph nodes, and brain inflammation also possible.

21. Rickettsialpox

Mites from both house mice and wild rodents carry this form of spotted fever. It can be found worldwide.

Like many forms of typhus, Rickettsialpox can be deadly if not treated promptly. It tends to present with typical typhus symptoms.

22. Relapsing Fever

Another tick-borne disease, Relapsing Fever is highly correlated to rodent infestations in rustic wood cabins in the mountainous regions of the U.S.

The most commonly seen symptoms of the bacterial disease is a relapsing high fever. The fever might last a few days, seemingly disappear for a week, then return for another few days. Headaches and body aches may accompany the fever, and may also recur. Without treatment, the pattern might continue for some time, but the disease is rarely fatal.

23. Rocky Mountain Spotted Fever

Despite its name, this illness is found throughout the United States, carried by ticks from infected rodents and dogs.

While the disease is named for a distinctive spotty rash, it may not appear until late in the disease and 10% of cases don’t develop any rash. Other symptoms include fever, headache, nausea, vomiting, muscle pain, abdominal pain, and red eyes. Rocky Mountain Spotted Fever is incredibly serious, and can kill a previously healthy person in 8 days if not treated correctly and quickly.

24. Sylvatic Typhus

The Sylvatic Typhus is another strain of typhus fever that can be passed to humans from rodents through louse, and it occurs throughout North America and in many other parts of the world.

Typhus is a serious disease, and should be treated as quickly as possible to avoid complications and death.

25. Rabies

Rodents can carry the rabies virus, which is most often transmitted through bites via saliva. If you have been bitten by a rodent or any other mammal, and do not know if it has rabies, you should immediately seek medical attention.

Rabies infections begin with flu like symptoms before progressing to more severe symptoms such as anxiety, confusion, agitation, aggression, hallucinations, insomnia, and hydrophobia. Once a patient begins to exhibit the symptoms of rabies, the chances of survival are slim.

When to Contact a Professional Rodent Control Company.

If you have a rodent infestation in your home, you and your family are at a serious risk for disease. Calling Colonial Pest’s professional rodent control and removal service is the safest and fastest way to remove the problem before it becomes a real threat. If you suspect you have an infestation, don’t delay in reaching out to us!

All disease information sourced from the Center for Disease Control.