Hantavirus Overview
Hantaviruses can infect and cause serious disease in people worldwide. People get hantavirus from contact with rodents like rats and mice, especially when exposed to their urine, droppings, and saliva. People mostly contract hantavirus by breathing in the virus. It can also spread through a bite or scratch by a rodent, but this is rare. Andes virus, which is found in South America, has reportedly had person-to-person transmission.
Hantaviruses cause two syndromes. Hantaviruses found in the Western Hemisphere, including here in the U.S., can cause hantavirus pulmonary syndrome (HPS). The most common hantavirus that causes HPS in the U.S. is spread by the deer mouse. Hemorrhagic fever with renal syndrome (HFRS) is a group of clinically similar illnesses caused by hantaviruses found mostly in Europe and Asia. However, Seoul virus, a type of hantavirus that causes HFRS, is found worldwide, including in the United States.
Veterans have been impacted by hantavirus, particularly during military service involving exposure to rodents in environments like Korea and during training exercises.
High-Risk Environments:
- Military environments: especially during operations involving soil disturbance, can increase the risk of exposure to rodents and their excreta.
- Korean War: Hantavirus was a significant problem for U.S. military personnel during the Korean War (1950–1953), though it was not identified as the cause until much later.
- Training Exercises: A cluster of cases among Canadian, U.S., and UK military personnel occurred after a large-scale training exercise in Alberta, Canada, due to exposure in a field environment.
Hantavirus Types
Hantavirus Pulmonary Syndrome (HPS)HPS is a severe and potentially deadly disease that affects the lungs. Symptoms usually start to show 1 to 8 weeks after contact with an infected rodent. HPS initially causes flu-like symptoms that can progress to more severe illness and trouble breathing. Important to begin treatment as early as possible to improve chances of recovery. Fatal in nearly 4 in 10 people infected.
Hemorrhagic Fever with Renal Syndrome (HFRS)HFRS is a severe and sometimes deadly disease that affects the kidneys. Symptoms of HFRS usually develop within 1 to 2 weeks after exposure. In rare cases, they may take up to 8 weeks to develop.
Hantavirus Signs and Symptoms
HPS symptoms may include:
- fatigue
- fever
- muscle aches, especially in the large muscle groups
- headaches
- dizziness
- chills
- abdominal problems, like nausea, vomiting, diarrhea, and abdominal pain
Four to 10 days after the initial phase of illness, the late symptoms of HPS appear. These symptoms include coughing and shortness of breath. Patients might experience tightness in the chest, as the lungs fill with fluid. HPS can be deadly. Thirty-eight percent of people who develop respiratory symptoms may die from the disease.
HFRS symptoms begin suddenly and may include:
- intense headaches
- back and abdominal pain
- fever/chills
- nausea
- blurred vision
- flushing of the face, inflammation or redness of the eyes, or a rash
- low blood pressure
- lack of blood flow (acute shock)
- internal bleeding (vascular leakage)
- acute kidney failure, which can cause severe fluid overload
The severity of the disease varies depending on the virus causing the infection. Hantaan and Dobrava virus infections usually cause severe symptoms where 5-15% of cases are fatal. In contrast, Seoul, Saaremaa, and Puumala virus infections are usually more moderate with less than 1% dying from the disease. Complete recovery can take several weeks to months.
Hantavirus Risk Factors
Anyone who has contact with hantavirus-carrying rodents, or their droppings, urine, saliva or nesting material is at risk of HPS. Rodent infestation in and around the home remains the primary risk for hantavirus exposure. Even healthy individuals are at risk for HPS infection if they have contact with the virus.
Cases normally occur in rural areas where forests, fields, and farms offer habitats for rodents. The animals can get into homes and barns, where they may leave urine or feces. Dogs and cats are not known to become infected with hantavirus in the United States. Pets may bring infected rodents to people or into homes.
How it spreads
- Each hantavirus has one primary rodent that carries the disease. The most common hantavirus that causes HPS in the U.S. is spread by the deer mouse.
- People can contract hantavirus if they have contact with urine, feces or saliva of a rodent carrying the virus. This can occur when people:
- Breathe in hantavirus-contaminated air when cleaning up after rodents.
- Touch contaminated objects and then touch their nose or mouth.
- Are bitten or scratched by an infected rodent.
- Eat food contaminated with hantavirus.
Hantavirus Treatment
Assessing patients for hantavirus can be difficult early in the infection because symptoms are non-specific and resemble many other viral infections. There is no specific treatment for hantavirus infection. Patients should receive supportive care, including rest, hydration, and treatment of symptoms.
HPS can cause breathing difficulties, and patients may need breathing support, such as intubation. Intubation is a medical procedure where a tube is placed in the lungs from the mouth to help the patient get oxygen.
HFRS can disrupt kidney function. Patients with HFRS may need dialysis to remove toxins from the blood and maintain the right balance of fluids in the body when the kidneys aren’t working well.
Other Resources and Support
CDC is available to consult or provide diagnostic testing. Clinicians can reach out by calling the CDC Emergency Operations Center at 770-488-7100 and requesting the on-call epidemiologist that handles hantavirus.
https://www.cdc.gov/hantavirus/about/
https://www.cdc.gov/hantavirus/hcp/clinical-overview/index.html
https://ndc.services.cdc.gov/case-definitions/hantavirus-pulmonary-syndrome-2015/
https://pubmed.ncbi.nlm.nih.gov/36099403/
https://www.army.mil/article/218344/headed_outdoors_familiarize_yourself_with_hantavirus
https://www.researchgate.net/publication/372249482_Hantavirus_Infections_among_Military_Forces