'South Korea has multiple cases every year': Indian doctors on Hantavirus risk

Some diseases are a result of the interaction between the natural habitat and the demographic vulnerability of the nearby population, said an infectious disease expert.

As the Hantavirus-hit MV Hondius anchored off the Canary Islands (Spain) and the process of de-boarding is almost complete, the remaining passengers have started to fly home with help of military and government planes. This also includes two Indians aboard who have been flown to the Netherlands and have been kept under observation.

As per the Embassy of India in Madrid, the two Indian crew members are ‘healthy and asymptomatic.”

Reportedly, they will be kept in quarantine as per the established safety protocols in the country.

However, this raises another concern of whether Indians should worry about the spread of the virus or is it just a regional threat.

As per Indian doctors, the virus carries low public health risk and spreads differently than other viruses like the Covid-19 which are highly contagious.

The Aedes strain

Hantaviruses are a family of viruses that are capable of causing serious illness in people and even death, the Centers for Disease Control and Prevention (CDC) have said.

Aedes virus is a type of Hantavirus spread by rodents in South America, including Argentina and Chile. 

While most forms of the virus transmit the disease through rodents and their excretions, this notorious type can in rare circumstances spread between humans.

The signs and symptoms for this disease can show as early as 4 days and as late as 42 days after exposure.

Early symptoms are often confused for flu as they include fever, chill, fatigue and abdominal discomfort.

In no time, these symptoms can progress into severe respiratory failure with liquid entering into the lungs and can affect multi organ functioning. 

In this case, the fatality rate is as high as 50 percent, said the Medical News Today.

The virus form is usually found in places which are dry and it is shed in urine and feces of the rodents.

When people stir up dust, the aerosol containing the virus can get into one’s respiratory tract.

Speaking to DH, Dr. Aravinda S N, a senior consultant in Internal medicine at Aster RV Hospital (Bangalore) said: “The virus has not shown the capacity to spread through large population groups. Most hantavirus strains which exist in North America and other regions of the world do not transmit between people.”

Likewise, the World Health Organisation (WHO) also said that human-to-human transmission of the virus only occurs through ‘intimate contact’ and the public health risk is usually low.

Indian doctors on Hantavirus

As per Indian doctors, the disease will not  necessarily escalate to an epidemic or a pandemic.

If a disease spreads within a community or region, it is termed an epidemic and if it happens to cross borders, it is called a pandemic. As per experts, Hantavirus is neither of the two and the ship cruise outbreak has been considered a limited exposure.

Speaking to DH, Dr. Yogiraj Ray, Associate professor and Head, Infectious Diseases at the Institute of Post Graduate Medical Education & Research (IPGME&R) (Kolkata) said: “Every year, Korea has many cases of Hantavirus, so did it spread to other parts of the world? No, right? Some diseases are a result of the interaction between the natural habitat and the demographic vulnerability of the nearby population. It just happened that all those people from 28 nationalities were together at the same time. The virus can be life threatening but it is also rare to get a diagnosis for it. In my view, the situation isn’t that worrisome if people who got exposed are kept isolated and all relevant measures are practiced.”

As per a BBC report, the illness was also explainable for the passengers who visited wildlife rich areas in Argentina.

A reported bird-watching activity could have exposed the passengers to rodent exposure.

Also, some speculations are around the ship being a harbour of the virus for which it is under inspection.

Some Indian doctors are also pointing out the species of mouse under consideration which can shift the risk.

Speaking to DH, Dr. Suchismitha Rajamanya, a senior consultant (Internal medicine) at Aster Hospital (Whitefield, Bengaluru) said: “The common house mice (Mus musculus) are generally considered low-risk carriers for the main hantavirus strains linked to severe human disease in North America. Studies and public health reports suggest deer mice remain the principal reservoir, with approximately 10–14 percent of deer mice in endemic regions carrying the virus. So regionally, our community is not at risk.”

However, Dr. Aishwarya R, a consultant in infectious diseases at Aster raised a concern that if an asymptomatic person, who was initially exposed to the virus, returns to the country and develops symptoms here, then it can be a little worrisome but later reassured the spread can only happen in a very close contact with the infected person’s secretions and the virality rate is not as high as in Covid-19.

Most doctors in India agree on the virus not being easily transmitted from one person to another. So, the public health risk assessment remains low in India.

Precautions to take

To protect oneself from Hantavirus, doctors have urged people to stay away from rodents and avoid coming in direct contact with their droppings.

Speaking to DH, Dr. Samir Garde, Director of Department of Pulmonology and Lung Transplant, Gleneagles Hospital (Parel) said: “ If a cruise or a group of individuals gets affected, it can be because of shared exposure to contaminated surroundings rather than direct human transmission. So, wearing gloves and masks while cleaning dusty enclosed spaces can also help to reduce the risk to a great extent.”

Rodent entry into homes, food storage areas and workplaces can be prevented by maintaining cleanliness throughout these spaces. When someone cleans up rodent droppings, they must not use sweeping or vacuuming methods to remove dry waste because this method will release infectious particles into the atmosphere, said experts.