Select Page

Home  ›  Hantavirus

Hantavirus

What is it?

Hantaviruses are a group of more than 20 zoonotic viruses primarily carried by rodents. Human infection most commonly occurs through the inhalation of air contaminated with the virus, or, less frequently, through direct contact with an infected rodent or rodent bites. (1) Each hantavirus is typically associated with a specific rodent host species, such as mice, rats, or voles, in which the virus establishes long-term infection without illness in the animal. (2, 3)

Hantavirus infections are relatively uncommon worldwide. In 2025, eight countries within the Americas reported a total of 229 cases, including 59 deaths. (4) In Europe, 1885 cases were reported in 2023. (4) In East Asia, case numbers have been declining, although several thousand cases are still reported annually. (4)

On 2 May 2026, a cluster of severe respiratory illness among passengers aboard the MV Hondius cruise ship was reported to the World Health Organization. (4) By 4 May, seven cases had been identified, including three deaths, three individuals with mild symptoms and one critically ill patient. The situation has continued to evolve, as of 26 May, there have been a total of 13 cases reported, 11 confirmed and two probable, including three confirmed deaths. (5, 6)

The cruise ship departed Argentina on 1 April 2026, carrying 147 passengers and crew. Symptom onset among affected individuals occurred between 6 April and 28 April. (4) The WHO currently assesses the global public health risk associated with this outbreak as low, and continues to monitor the situation closely. (4)

Signs and Symptoms

Hantavirus infections present as two different patterns of illness, depending on the strain of virus involved.

Haemorrhagic fever with renal syndrome (HFRS) is primarily found in Europe and Asia and represents a group of illnesses caused by hantavirus. (1, 7) Symptoms typically develop within one to two weeks, although incubation periods of up to eight weeks have been reported. (7)

Symptoms begin suddenly and include fever, headache, blurred vision, back and abdominal pain, progressing to kidney failure and haemorrhage in more severe cases. (1, 7) Disease severity varies by viral strain, with the Hantaan and Dobrava virus, commonly associated with mice in Asia, having a fatality rate of 5-15%. (1) In contrast, the Puumala virus, which circulates through Europe, has a lower fatality rate of less than 1%. (1, 7) Recovery of HRFS can be prolonged, taking several weeks to months. (7)

Hantavirus pulmonary syndrome (HPS) occurs predominantly in the Americas and is typically more severe. (1, 7) Symptoms usually develop one to eight weeks after exposure to infected rodent material. Early symptoms are non-specific and may include influenza-like symptoms, fever, muscle aches, and fatigue. However, within four to 10 days after the initial symptoms, late symptoms can develop and rapidly progress to severe respiratory failure, with a fatality rate of over 35 %. (1, 7)

There are no specific treatments or vaccines available for hantavirus infections. Management is primarily supportive, including rest, fluid management and treatment of symptoms as they arise. (4, 7)

How is it transmitted?

Human infection with hantavirus is rare and most commonly occurs through the inhalation of aerosolised particles contaminated with the faeces, urine or nesting materials of infected rodents, or through direct contact with the urine, faeces or saliva of an infected rodent. (8)

Certain activities, such as cleaning, farming or camping, can disturb contaminated dust and rodent excretions, and increase the risk of airborne/inhalational exposure. (1)

Person-to-person transmission is not typical of most hantaviruses, and infections generally occur as isolated cases. (1) The notable exception is the Andes virus, found in South America, which is the only known hantavirus capable of person-to-person transmission. (1, 7) In these cases, transmission has been reported primarily after close and prolonged contact with a symptomatic individual; however, the possible role of inhalational transmission has not been ruled out. (9) Andes virus infection is associated with a high case fatality rate of 35-50%. (1, 2)

The risk of hantavirus in Australasia.

Australia remains the only inhabited continent with no confirmed cases of human hantavirus. (1) Despite this, ongoing surveillance is important, particularly given the presence of rodent populations.

Environmental factors, including climate variability and events that increase food availability, can lead to surges in rodent populations. Such increases have been associated with subsequent rises in human hantavirus cases in other regions. (2)

Reducing risk of exposure.

Reducing the risk of hantavirus infection relies on minimising contact between people and rodents. (2, 7) Key prevention strategies include maintaining clean living and working environments, sealing potential entry points in buildings, storing food securely and implementing safe cleaning practices to limit dust generation. (2, 7)

Early recognition of suspected cases, together with prompt isolation and strict adherence to infection prevention and control (IPC) measures, is critical. (4) Given the high fatality rate of the Andes virus infection and the uncertainty surrounding its transmission route, a precautionary approach is recommended when implementing IPC and transmission-based precautions. (9) Recommended measures include the application of standard and transmission-based precautions, patient isolation, and airborne precautions during aerosol-generating procedures. (4) The European Centre for Disease Control (ECDC) further advises placement of patients in a negative-pressure isolation room, airborne precautions with healthcare workers using particulate filter respirators (PFR). (9)

For the MV Hondius outbreak, contact management has been risk-based. High-risk contacts, defined as individuals with known exposure to a probable or confirmed case, are required to isolate for 42 days following their date of last exposure, with active daily monitoring by public health authorities. (10) Low-risk contacts, those who have attended a shared setting with a probable or confirmed case, but do not meet high-risk definitions, must self-monitor for 42 days from the date of last exposure, without restrictions on occupational or recreational activities. (10)

References

  1. CSIRO. Hantavirus: the ‘silent’ virus: CSIRO; 2026 [Available from: https://www.csiro.au/en/news/All/Articles/2026/May/Hantavirus-explainer
  2. World Health Organization. Hantavirus: WHO; 2024 [Available from: https://www.who.int/news-room/fact-sheets/detail/hantavirus
  3. Avšič-Županc T, Saksida A, Korva M. Hantavirus infections. Clin Microbiol Infect. 2019;21s:e6-e16.
  4. World Health Organization. Hantavirus cluster linked to cruise ship travel, Multi-country: World Health Organization; 2026 [Available from: https://chatgpt.com/c/6a052814-8d34-83ec-947a-888ff2f25d9f.
  5. European Centre for Disease Prevention and Control. Andes hantavirus outbreak in cruise ship, 13 May 2026. European Centre for Disease Prevention and Control; 2026 13 May 2026.
  6. European Centre for Disease Prevention and Control. Andes hantavirus outbreak: European Centre for Disease Prevention and Control; 2026 [Available from: https://www.ecdc.europa.eu/en/infectious-disease-topics/hantavirus-infection/surveillance-and-updates/andes-hantavirus-outbreak.
  7. Centers for Disease Control and Prevention. About Hantavirus Atlanta: CDC; 2024 [Available from: https://chatgpt.com/c/6a052814-8d34-83ec-947a-888ff2f25d9f.
  8.  Australian Center for Disease Control. Hantavirus risk in Australia remains low Canberra: Australian Centre for Disease Control; 2026 [Available from: https://www.cdc.gov.au/newsroom/news-and-articles/hantavirus-risk-australia-remains-low.
  9. European Centre for Disease Prevention and Control. Rapid scientific advice on infection, prevention and control measures for patients in healthcare settings with Andes virus (ANDV) disease. Stockholm, Sweden: ECDC; 2026 15 May 2026.
  10. World Health Organization. Management of contacts of Andes virus (ANDV) cases from the MV Hondius cruise ship: World Health Organization. ; 2026 [Available from: https://chatgpt.com/c/6a052814-8d34-83ec-947a-888ff2f25d9f.