Prof Jonathan Ball

Okay, so Hantavirus is a virus that circulates widely in rodents.

There are different species of Hantavirus across all continents except Antarctica, although there may well be

Some rodents live in there that could possibly have the hantavirus.

I'm not sure we've extensively checked.

But essentially, we can divide the hantaviruses into two main groups.

The new world hantaviruses, which mainly are found in the Americas, for example.

and the old world hantaviruses, which are in places like Africa, Asia, and also Europe.

The new world hantaviruses can cause what we call hantavirus pulmonary syndrome, which is quite a severe respiratory problem.

It can really interfere with your ability to breathe correctly.

Whereas the old world ones can cause hemorrhagic fever with renal problems as well.

Humans become infected when they become exposed predominantly to rodent urine or faeces, basically the rodent excretia.

And particularly as it dries, it can form little particles that can become airborne and then people acquire the virus when they breathe in these contaminated particles.

And anybody who is exposed to rodents regularly is at increased risk of getting a hantavirus infection.

So human-to-human transmission is rare, but there is some evidence of transmission amongst people who are in very close proximity, so family members, for example.

And we certainly know that there is...

risk of transmission for healthcare workers.

And it can occur through either contact with contaminated materials that the person is producing, but I think there's also evidence of sexual transmission.

Well, it's almost difficult to come up with a definitive answer on that, and I'm not hedging my bets.

The reason I say that is that most infections are probably either asymptomatic or mild.

So we think there's between 100,000 and 200,000 cases of hantavirus infection around the world, but that's probably the tip of the iceberg, and very, very few of those infections will result in serious disease.