Late this afternoon, the World Health Organization issued this warning.

The whole world needs to be on alert now.

The whole world needs to take action and be ready for for any cases that come either from the original epicenter or from from other every centers that become established.

Hen and surrounding cities remain in virtual lock down villages, even barricading themselves against a virus that does not respect borders.

And the W.

H.

O has also announced that tomorrow it will reconvene.

It's committee to decide if this is a public health emergency, off international concern that would trigger an international response.

But the team, who has just returned from China, praised the country for its handling of this outbreak.

The fact that to date we have only seen 68 cases outside China and notice is due in no small part to the extraordinary steps the government has taken to prevent the export off cases.

For that, China deserves our gratitude and respect and they're doing that at the expense off their economy and other factors.

There is no end in sight, though confirmed cases and now just under 6000 more than the number and China infected during the SARS outbreak in the early two thousands.

The death toll has also risen to 132 on now.

Airlifts of foreigners from Hu Bei province have begun.

Four passengers on the evacuation flight to Japan head coughs and fevers and two were diagnosed with pneumonia.

Although it's not confirmed that they have Corona virus tomorrow, Britain's who want to leave will be flown out, but wives or partners with Chinese passports will have to remain behind and those who do return will be put into quarantine for 14 days, the incubation period for the virus.

We should be reassured that the N hs is well set up to deal with with the sort of infectious disease public health England have done lots of training on dhe, the N hs executive of sent out information to all conditions and GPS, so it's really up to the public to take some responsibility here as well.

The source of it is still unknown.

The theories are up, maybe like SARS in bets and transmitted to humans.

Vira Wild Animals sold at the Wu Han seafood market A crackdown was earlier this week announced on the sale of these creatures.

But that came too late to prevent this outbreak.

And health experts continue to say the best protection is handwashing, staying at home if you feel unwell and keeping away from those who are sick.

Victoria McDonald reporting Now joining us is doctor Rosalyn Egger, who works in public health epidemiology.

And I'm wondering, Are we any clearer about the cause of this outbreak?

Yes, so we know that this is caused by a Corona virus.

And Corona viruses are a family of viruses that infect people and animals all around the world.

And there's really very, very new evidence now from the genetics of the virus that it's closely related to something that exists in bats.

But we don't yet know how it came into human, so whether it was from backed into people or from bats into an intermediate host and then into people.

But what we do know, it's clear that this is a duel, not IX Phil, over so a circuit of virus that circulates in animals bred into people.

And now we have person to person transmission between people.

Now you model public health epidemics.

Some scientists have models that suggest maybe 100,000 cases will flow from this outbreak.

What does that tell you?

So at the very beginning of Operation Epidemic we is.

There's a lot of uncertainty, especially around key characteristics off the virus.

So, for example, from when somebody gets infected toe when they start to become symptomatic, or when do they start to shed virus?

Thes durations are very important, and that means these early estimates there's a lot of uncertainty.

There's a there's a wide window off what we might expect to see, And as time goes on and we learn Maur, our confidence in our estimates will come down, and that will allow us to better understand what we expect to see.

Is it sensible to airlift people out off China?

So repatriating Britain's is perfectly fine policy, and the key thing is that even within Wuhan, this is enormous city.

There are a lot of cases but on an individual level, it's still quite it's unlikely that the people will be infected.

But as was mentioned there, the people coming back are going to be closely looked after and monitored.

So if they do show symptoms or if they, uh, then they'll get, you know, medical assistance as quickly as possible.

And there's very unlikely there'll be any transmission into the community now, actually heard there's somebody of the W H O saying that they're only 68 cases in the whole of the rest of the world.

Do we accept is expected, a spike.

So right now, as I mentioned, there's this incubation period, the time for when you get infected toe when symptoms start to show.

And we think this is on average five or six days.

But in some people can be as long as two weeks with mentioned.

And so some of the cases that we're seeing now that have been exported are from further back in transmission.

They happened quite a a few days ago before some of these interventions happened in China.

So right now we have to wait and see if these interventions that have been put in place in Wuhan and other places have had an impact on the transmission.

The W H O committee is meeting tomorrow to decide whether to declare an international emergency.

What do you think they'll do?

So there's a really critical point in the outbreak, really critical time.

And regardless of whether they declare a public health emergency of international concern tomorrow, what we need is increased collaboration, increased transparency.

And that's what that global health community working together is really what's gonna stop this outbreak.

But if they do determine that it should be on international emergency, what does that mean?

It means that they'll be particular activities that happen in certain countries, and that'll really bring together the collaboration amongst countries.