According to Google Trends, the top globally trending topic this week is “orthohantavirus”, as spurious sites claim it’s the next pandemic on the horizon.

Take it from me: it’s not.

This baseless claim circulating online underscores the need to get health information from reputable sources – and that you shouldn’t believe everything you read on social media.

What is orthohantavirus?

“Orthohantavirus” - commonly known as hantavirus – is a very, very rare virus. There have never been confirmed human cases in Australia. The last two reported confirmed cases worldwide were in January in Bolivia and Argentina.

It is in a class of diseases called zoonoses, meaning it is a virus transmitted from animals to human. In this case, the animal in question is rodents (usually rats). Hantaviruses can cause severe disease, including bleeding and kidney failure.

Read more: Health Check: what bugs can you catch from your pets?

How does hantavirus spread?

According to the US Centers for Disease Control and Prevention (CDC), hantavirus is spread from several species of rodents in their urine, droppings, and saliva. It is thought that transmission occurs when they breathe in air contaminated with the virus.

CDC also reports:

• if a rodent with the virus bites someone, the virus may be spread to that person, but this type of transmission is rare;
• scientists believe that people may be able to get the virus if they touch something that has been contaminated with rodent urine, droppings, or saliva, and then touch their nose or mouth;
• scientists also suspect people can become sick if they eat food contaminated by urine, droppings, or saliva from an infected rodent.

How worried should I be about hantavirus?

Not very. In general, infectious disease specialists do worry about zoonoses – the coronavirus that causes COVID-19 and Ebola are both important recent examples of animal-associated diseases that have crossed the species barrier.

Hantavirus, however, is not thought to be a big threat at the moment.

There’s certainly no chatter among infectious disease physicians about hantavirus right now. I’m not seeing anything concerning about it on any of my researcher networks and mailing lists that warn about virus outbreaks.

There was a recent report of a single case in China but there’s no indication of any sort of spread.

I think, for now, let’s concentrate on the pandemic we have – which is coronavirus and also the annual influenza season – rather than worry about uncommon viruses.

However, this coronavirus outbreak and everything that’s come before reinforces that we need early warning systems to work out what’s out there that could be threatening.

Yes, it is true that animals carry a lot of viruses but very few come across to humans.

Hantavirus is certainly not one we are particularly concerned about right now.

Read more: How does coronavirus kill?

Allen Cheng receives funding from the National Health and Medical Research Council. He is affiliated with the Australasian Society of Infectious Diseases, and is a member of government advisory committees, including those involved with COVID-19.