hantavirus

Hantaviruses are a group of microscopic RNA viruses in the family Hantaviridae that are carried mainly by rodents. These viruses are extremely small—typically about 80–120 nanometers in diameter—and are surrounded by a lipid envelope covered with glycoprotein spikes that help them attach to host cells. Inside, they contain single-stranded, negative-sense RNA divided into three segments, along with proteins that protect and organize the viral genome. Similar to other viruses, hantaviruses cannot reproduce on their own and must invade living cells to replicate, relying entirely on the host’s cellular machinery to produce new virus particles.

Hantavirus infections in humans are caused by exposure to viruses carried by infected rodents. The virus is typically transmitted when people inhale airborne particles contaminated with rodent urine, droppings, or saliva, especially in enclosed or poorly ventilated spaces. Less commonly, infection can occur through direct contact with contaminated materials, rodent bites, or touching the mouth, nose, or eyes after handling contaminated surfaces.

Different hantaviruses are carried by different rodent species, but in North America the primary carrier is the deer mouse (Peromyscus maniculatus), which is associated with hantavirus pulmonary syndrome (HPS). Other rodent hosts include the cotton rat, rice rat, and white-footed mouse. In Europe and Asia, hantaviruses are more commonly carried by rodents such as bank voles and striped field mice. These various animals can harbor the virus without becoming ill and shed it through their urine, droppings, and saliva.

Hantavirus can be introduced onto cruise ships when infected rodents gain access, often by traveling unnoticed in cargo, food shipments, or while the vessel is docked. Once onboard, these animals may contaminate enclosed areas such as storage rooms or lower decks. The virus can then be transmitted if tiny particles from rodent droppings, urine, or saliva become airborne, particularly when contaminated materials are disturbed, allowing them to be inhaled.

Symptoms of hantavirus infection often begin with fever, fatigue, muscle aches, headaches, and chills, sometimes accompanied by nausea or abdominal pain. In hantavirus pulmonary syndrome (HPS), the illness can rapidly progress to coughing and severe shortness of breath as fluid accumulates in the lungs. In hemorrhagic fever with renal syndrome (HFRS), symptoms may also include low blood pressure, bleeding problems, and kidney dysfunction. Because early symptoms resemble those of influenza, hantavirus infections can be difficult to recognize in their initial stages.

Yes, hantavirus infection can be survived, particularly with early diagnosis and supportive medical care. Survival rates depend on the specific form of the disease, with hantavirus pulmonary syndrome (HPS) being more severe because it can cause serious breathing difficulties. Prompt treatment, including hospitalization and respiratory support, can significantly improve the chances of recovery.

The death rate from hantavirus infection depends on the specific disease it causes. Hantavirus pulmonary syndrome (HPS), found mainly in the Americas, has a case fatality rate of about 35–40 percent, making it a highly dangerous infection. Hemorrhagic fever with renal syndrome (HFRS), more common in Europe and Asia, varies in severity depending on the viral strain, with death rates ranging from less than 1 percent to about 15 percent. Early diagnosis and supportive medical care can improve survival.

The two main groups of hantavirus diseases are hantavirus pulmonary syndrome (HPS) and hemorrhagic fever with renal syndrome (HFRS). HPS, most commonly reported in the Americas, primarily affects the lungs and can lead to severe respiratory distress, while HFRS, found mainly in Europe and Asia, affects the kidneys and can cause bleeding and renal failure.

Hantavirus infections can be prevented by reducing exposure to rodents and their contaminated materials. This includes sealing homes and buildings to keep rodents out, safely cleaning areas with rodent droppings or nests using disinfectants (rather than sweeping or vacuuming, which can spread particles into the air), and maintaining clean surroundings to avoid attracting rodents. When working in areas where rodents may be present, such as sheds or cabins, it is important to ventilate spaces and use protective gear, such as gloves and masks, to minimize the risk of inhaling contaminated dust.