One very rare positive effect off the past few months has been on the environment.

Biggest ever reduction in the volume of carbon dioxide released into the world's atmosphere has been recorded since March.

At the height of the lock down, scientists discovered the daily emissions around the world dropped by more than 17%.

The biggest fall was in China, which saw a drop in emissions of 24%.

Here in the UK, the reduction was 13%.

But scientists are warning that this extreme reduction, as they call it in greenhouse gas emissions, is likely to be temporary.

Is our science editor David Shipman explains.

All over the world, some stunning transformations from choked streets in India becoming calmer and easier to breathe in to the most famous landmark in China, suddenly looking clear to the center of Paris, often polluted now quarter and clean, the fight against the virus has slowed down many economies at huge cost.

But it's also done wonders for the air and for the carbon emissions that air heating up the planet.

The drop in traffic is a major part of that here in the UK and globally, lower demand for electricity has also made a difference.

Along with the grounding of planes, fewer flights means less carbon released into the air.

It's a pattern seen around the world.

The light of the shade here, the bigger the decline in emissions in some countries up again, but still a huge change.

The full in emissions we're seeing 17% today is enormous.

We haven't exp periods something like this before, as far as we can tell, that is driven by changes in road transport.

But now that China's out of lock down traffic, there is building up, so emissions are rising once again, Theo carbon cut is not permanent on some key roads.

The traffic is starting to come back a bit.

PSAs.

The lock down is eased.

But the impact of the different restrictions on the environment has been really striking not only of those carbon emissions down, the quality of the air has got a lot better.

Different types of pollution have fallen dramatically, so as the economy recovers, will we see a return to the toxic haze hanging over our cities?

Experts in air pollution hope the crisis has shown what's possible that very unfortunate natural experiment, but It doesn't really show us that by changing the vehicles on our roads or reducing the vehicles around or changing over to electric vehicles, we can immediately reduce air pollution, which that very, very important message.

Many cities are now trying to encourage more cycling and walking to help keep people safe from the disease and also to reduce pollution.

The hope is that amid the nightmare of the virus, a greener future can be created.

David Shortland, BBC DEAR Leaders off Birmingham City Council have sent a letter to parents and school staff saying they will only support schools.

Opening two more pupils when it is safe to do so follows on from other city councils, including Liverpool.

The Voice.

Similar concerns.

Earlier this month, the government set out plans for schools in England, potentially reopening to more pupils from the start off June.

Cambridge University has announced it will move all of its lectures online until the summer off 2021.

As a result off the pandemic, it said, smaller teaching groups may continue in person, provided social distancing can be maintained.

University stressed it will keep the situation under review on din line with official advice The Premier League has said that there were six positive tests for Corona virus in three clubs tested over the past few days.

The announcement came as some teams returned to group training for the first time since the lock down began.

A total of 748 players and star from 19 clubs have so far been tested on the six.

Testing positive in this batch will now self isolate for a week now in the U.

S.

President Trump has been widely criticized by health experts following his admission that he was taking an anti malaria drug to protect himself against the virus after two people in the White House tested positive for the disease.

Regulators have warned that there's no evidence that he provides any protection from Cove in 19 on May indeed cause heart problems.

President has continued his attacks on the World Health Organization, calling it a puppet of Beijing, which failed to hold China to account for the original outbreak.

He says.

Our correspondent Nick Bryant has the latest.

The White House is one of the most heavily protected buildings on the planet, guarded by Secret Service agents ready to take a bullet for the president.

But in the midst of this viral onslaught, can they protect Donald Trump from himself?

Last night, he happily made a stunning admission that defend off the Corona virus.

He's taking an anti malaria drug, high drop sick Laura Quinn, that his own government has warned against using for covert 19 out of fear of the fatal consequences.

I happen to be taken it.

I happen to be taking it.

Actually, I'm Jenkin and Hydroxy Quinn right now.

Yeah, a couple of weeks ago started taking it because I think it's could have heard a lot of good stories.

And if it's not good, I'll tell you, right?

The doctor to get hurt by it.

It's been around for 40 years.

This was the astonished response on Fox News, a network that's ordinarily the president's cheerleader channel.

If you are in a risky population here and you were taking this as a preventative treatment and toward off the virus or in a worst case scenario, you're dealing with the virus and you are in this vulnerable population, it will kill you.

I cannot stress enough this will kill you.

But even after being deluged by an acid shower of criticism.

Tonight on Capitol Hill, Donald Trump continued to prescribe the drug.

I think it gives you an additional level of safety.

But you can ask many doctors are in favor of it.

Many frontline workers won't go there unless they have the hydroxy.

And so again, this is an individual decision to make.

But it's had a great reputation, and if it was somebody else other than May, people would say G is in that smart.

He's also doubled down on his threat to hold US funding of the World Health Organization, which has been meeting mostly virtually in Geneva.

The U.

S president has bemoaned its repeated missteps, but its director general defended the global body.

For all our differences, we are one human race and we are stronger together, Many medical experts say.

It's not just the damage that Donald Trump could cause himself by taking this anti malarial drug.

It's the example he's setting to others In the midst of a crisis that has already claimed more than 90,000 American lives, they fear the president is dispensing dangerous and potentially faithful advice.