Hanta virus can cause diseases such as Hanta virus pulmonary syndrome (HPS) and hemorrhagic fever and urinary tract infection (HFRS).

The US media quoted the Centers for Disease Control and Prevention (CDC) as saying that the outbreak has been placed at ‘Level 3’. This means that an emergency response is required if the disease occurs. Kathmandu Post spoke to virologists, epidemiologists and health officials to find out what this infection is and what we need to know about it.

What is Hanta virus and how does it spread to humans?

Wild animals such as rats and mice are the main carriers of this virus. This virus can cause serious illness and death in humans. It affects the respiratory system, kidneys and lungs. According to the World Health Organization, it is transmitted through close contact with the feces, urine or saliva of wild animals such as rats and mice, or by touching or cleaning contaminated surfaces.

People in rural areas, who work in agriculture or on farms where there are wild animals such as rats and mice, are at risk of contracting this infection.

Why has the latest infection become a global concern?

According to the US Centers for Disease Control and Prevention, the mortality rate for Hanta virus is around 35 to 40 percent. In some outbreaks, it has been seen to reach 50 percent.

The outbreak has sparked global public health concern after at least three people died and several others were hospitalized with serious illness.

The MV Hondius, a luxury cruise ship that left Argentina, was carrying nationals from Argentina, Canada, Denmark, Germany, the Netherlands, the Philippines, Singapore, South Africa, Spain, Switzerland, the United Kingdom, and the United States. Some of the passengers on board were from Australia, Belgium, France, Greece, Guatemala, India, Ireland, Japan, Montenegro, New Zealand, Poland, Russia, Turkey, and Ukraine. The United Nations health agency has assessed the risk to the global population from the Hantavirus outbreak on the cruise ship as low.

Has Nepal ever had Hantavirus?

No one in Nepal has been confirmed to have Hantavirus so far. According to a report published by the US Centers for Disease Control and Prevention, a Spanish traveler who returned from a trip to Nepal in 2017 developed respiratory problems due to hantavirus. Researchers involved in the investigation suspect that the Spanish traveler may have come into contact with rats or mice while staying at a lodge in Nepal and contracted the infection.

Is it transmitted from person to person?

According to the World Health Organization, it is only transmitted from person to person when living in a closed room with an infected person or when the infection spreads in the community. However, such infections are very rare. Of the identified hantavirus variants, the Andean strain is the only variant that can be transmitted from person to person. This variant has been spreading from time to time in Chile and Argentina.

What do experts in Nepal say?

Although hantavirus has not been confirmed in Nepal yet, experts say the risk of its possible outbreak cannot be ruled out. Since there is a lot of international and domestic travel in Nepal, the risk of diseases occurring anywhere in the world remains here as well. Dr. Sher Bahadur Pun, Head of the Clinical Research Unit of Shukraraj Tropical and Infectious Diseases Hospital and an infectious disease specialist, referring to a patient who came to the hospital for treatment of a rat bite, said, “More than a dozen rat bite cases come to Nepal every day.” He said that many people die in Nepal due to respiratory diseases, but they do not know the real cause.

According to experts, no study has been conducted so far on whether or not rats in Nepal carry hantavirus.

Doctors at Dhulikhel Hospital have requested that swab samples of pneumonia patients be sent to the National Public Health Laboratory so that they can test whether the patients have hantavirus infection. Dr. Registrar of Kathmandu University Rajiv Shrestha said, ‘If you ask me after two weeks whether there is Hanta virus in Nepal, I can tell you with evidence.’ He, who is in charge of infectious diseases, antimicrobial resistance, drug and vaccine testing, metagenomics and whole-genome sequencing at Kathmandu University, added, ‘We have requested the National Public Health Laboratory to send the sample for genome sequencing. It will take two weeks to get the results.’

What are health officials doing?

Officials said they have discussed the possible outbreak of the deadly virus with the relevant stakeholders and have decided to start preparing for testing. For that, they are coordinating with the WHO Nepal office.

‘The necessary test kits for Hanta virus are not easily available in the market,’ said Dr. Runa Jha, director of the National Public Health Laboratory, ‘We are in close contact with WHO officials.’ WHO headquarters will help us provide the necessary reagents for testing or send suspected samples to a WHO laboratory abroad.’

What are the symptoms of infection and what is the treatment?

Hantavirus infection causes headaches, dizziness, chills, fever, muscle aches, and digestive problems such as nausea, vomiting, diarrhea, and abdominal pain. Then, there is a sudden onset of respiratory problems and high blood pressure. Symptoms may appear within two to four weeks after exposure to the virus, sometimes within a week or as late as eight weeks.

There is no specific drug, vaccine, or antiviral treatment for Hantavirus. Doctors only provide supportive care, so early detection is crucial.