Hantavirus Infection

Hantaviruses are a family of viruses which can cause serious illnesses and death. These viruses cause diseases like hantavirus pulmonary syndrome (HPS) and hemorrhagic fever with renal syndrome (HFRS).

Currently it is estimated that 150,000 to 200,000 cases of hantavirus disease occur each year, the majority being reported in Asia. However, human hantavirus infections are increasingly reported in the Americas and Europe. Despite the high morbidity and case-fatality rates of human hantavirus infections, no vaccine or drug is currently proven to be preventive or therapeutic.

There are more than 25 known hantavirus strains, each associated with specific rodent hosts and regions.

Signs and Symptoms

HPS

HPS is a severe and potentially deadly disease that affects the lungs. Symptoms of HPS usually start to show 1 to 8 weeks after contact with an infected rodent. Early symptoms can include fatigue, fever, muscle aches, especially in the large muscle groups like the thighs, hips, back, and sometimes shoulders. About half of all HPS patients also experience 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

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. Initial symptoms begin suddenly and include intense headaches, back and abdominal pain, fever/chills, nausea, and blurred vision. People may have flushing of the face, inflammation or redness of the eyes, or a rash.

Later symptoms can include low blood pressure, lack of blood flow, internal bleeding, and acute kidney failure, which can cause severe fluid overload. The severity of the disease varies depending on the virus causing the infection.

Global Threat

While hantavirus is a serious health threat, its global impact is generally limited compared to more widespread infectious diseases.

Changes in climate can alter rodent habitats and population dynamics, potentially increasing hantavirus transmission. Expansion of human settlements into rodent habitats can increase human-rodent interactions. Increased movement of people and goods can facilitate the spread of hantavirus to new regions. Inadequate public health infrastructure and lack of awareness can lead to delayed responses and higher infection rates.

Hantavirus transmission is primarily through direct contact with infected rodents, which limits widespread human-to-human transmission. Effective rodent control, public education, and proper sanitation can significantly reduce infection risk.

New or more virulent strains of hantavirus could pose a greater threat if they adapt to human hosts or if transmission dynamics change. Certain regions with high rodent populations and poor living conditions may experience more frequent and severe outbreaks.

Transmission

Each hantavirus has one primary rodent that carries the disease. Hantavirus primarily spreads to humans through contact with infected rodent urine, droppings, or saliva. The main routes of infection include inhalation of aerosolized virus particles from rodent excreta, direct contact by touching contaminated surfaces or objects and then touching the mouth, nose, or eyes. Rarely, infection can occur through bites from infected rodents.

Causes of Death

Deaths from hantavirus infections are typically due to severe complications arising from the virus.

Hantavirus Pulmonary Syndrome

Severe fluid accumulation in the lungs can lead to difficulty breathing and a lack of oxygen in the blood, and respiratory failure.

Severe fluid loss and leakage from blood vessels cause a drop in blood pressure, leading to cardiovascular shock and potentially fatal organ failure.

The combined effects of respiratory failure, shock, and direct viral damage can lead to the failure of multiple organs, including the heart and kidneys.

Hemorrhagic Fever with Renal Syndrome

Kidney failure due to vascular damage can lead to the inability to

remove waste from the blood, resulting in toxic buildup.

Vascular damage can lead to significant internal bleeding and hemorrhagic shock.

Severe drop in blood pressure can lead to circulatory collapse and death if not promptly treated.

Early detection and supportive care, including respiratory support and management of fluid and electrolyte imbalances, are crucial for improving survival rates in hantavirus infections.

Prevention

Preventing hantavirus infection primarily involves reducing exposure to rodents and their excreta.

Close gaps and holes in homes, garages, and sheds to prevent rodents from entering. Use traps to reduce rodent populations around living and working areas. Maintain a clean environment by removing food sources, storing food in rodent-proof containers, and keeping pet food and birdseed secured.

Before cleaning rodent-infested areas, ventilate the space by opening doors and windows for at least 30 minutes. Avoid stirring up dust. Do not sweep or vacuum rodent droppings, urine, or nesting materials, as this can aerosolize the virus.

Spray rodent droppings and nesting materials with a disinfectant or bleach solution (1 part bleach to 10 parts water) and let it soak for at least 5 minutes.

Protect yourself by wearing rubber or plastic gloves, and if dealing with heavy infestations, consider wearing a mask or respirator.

Workers in high-risk occupations should use appropriate personal protective equipment, including gloves, masks, and eye protection.