Orthohantavirus, often simply called hantavirus, is a genus of viruses within the Hantaviridae family. These viruses are naturally found in various rodent species globally, where they typically cause asymptomatic, persistent infections. However, when transmitted to humans, orthohantaviruses can lead to severe and potentially fatal diseases. The genus includes over 30 recognized species, each often associated with a specific rodent host.
How Orthohantavirus Spreads
Orthohantavirus transmission to humans primarily occurs through exposure to infected rodents or their excretions. The most common route of infection is by inhaling aerosolized viral particles from rodent urine, droppings, or saliva. These airborne particles can become suspended in the air when rodent-infested areas are disturbed.
Common scenarios for exposure include cleaning out sheds, barns, cabins, or other enclosed spaces where rodents have been active. Farmers, construction workers, and campers may also be at higher risk. While human-to-human transmission is generally rare, specific variants like the Andes orthohantavirus can cause person-to-person spread, primarily in South America.
Recognizing the Infection
Orthohantavirus infections manifest in humans primarily as two distinct syndromes: Hantavirus Pulmonary Syndrome (HPS) and Hemorrhagic Fever with Renal Syndrome (HFRS). HPS is typically found in North, Central, and South America, while HFRS is more common in Europe and Asia. Both conditions often begin with non-specific, flu-like symptoms.
Initial symptoms, appearing one to eight weeks after exposure, can include fever, muscle aches, fatigue, headaches, dizziness, chills, and abdominal issues like nausea, vomiting, or diarrhea. In HPS, these symptoms rapidly progress to severe respiratory distress. Patients develop coughing and shortness of breath due to fluid accumulation in the lungs.
HFRS progresses to affect the kidneys, leading to renal failure. Symptoms may also include low blood pressure, acute shock, and in some cases, hemorrhagic manifestations. Prompt medical attention is important if these symptoms develop, especially after potential rodent exposure.
Protecting Against Infection
Preventing orthohantavirus infection centers on effective rodent control and safe cleanup practices. Seal up holes and gaps in homes and other structures to prevent rodents from entering. Trapping rodents and maintaining clean environments, both indoors and outdoors, can also help reduce their presence.
When cleaning areas that may be contaminated with rodent droppings or urine, take these precautions to avoid inhaling viral particles:
- Ventilate the area for at least 30 minutes by opening windows and doors.
- Wear rubber or plastic gloves and a respirator mask, such as an N95 or higher, to protect against airborne particles.
- Before sweeping or vacuuming, thoroughly wet the contaminated surfaces with a disinfectant solution, such as a mixture of bleach and water (1 part bleach to 9 parts water).
- After soaking for at least 5 minutes, use paper towels to wipe up the materials, then seal them in a plastic bag and dispose of them.
- Disinfect any tools or reusable items used during cleanup before storage.
Diagnosis and Medical Care
Diagnosis of orthohantavirus infection relies on clinical symptoms and a history of potential rodent exposure. Laboratory tests then confirm the virus’s presence. These tests typically involve serology, which detects antibodies to the viral infection.
There is currently no specific antiviral cure for most orthohantavirus infections. Medical care focuses on supportive measures to manage symptoms and bodily functions. For HPS, this often involves oxygen therapy and, in severe cases, mechanical ventilation.
For HFRS, supportive care may include fluid management to maintain blood pressure and, if kidney failure occurs, dialysis. While a vaccine is available in some regions for specific hantaviruses that cause HFRS, it is not widely available for those causing HPS. Early diagnosis and prompt supportive care are important for improving patient outcomes.