Six counties in the San Francisco Bay Area say that masks with one-way valves do not meet their face covering requirements because they allow potentially infectious droplets to excape.

Face masks are being used to lift lockdowns in Italy, Austria and the Czech Republic - but do they work? Experts say fabric stops you breathing in droplets potentially carrying the virus.

Charities in the UK have warned the killer infection can lead to acute kidney injury (AKI), a sudden serious condition that can be fatal if not treated immediately.

DR ELLIE CANNON: The Mail on Sunday's GP discusses B&Q reopening, pictured, how to obtain a free test, whether it's safe to hug grandchildren and more in this week's column.

DR MARTIN SCURR: Any persistent problem can be terribly frustrating but it is not the Barrett's oesophagus (pictured) that is causing your symptoms.

A walk in the park could cause hayfever sufferers to sneeze, even if the pollen count is low, a US-German study has found. Research on 25 men found even a simple smell could trigger hayfever symptoms.

One sample collected from an Arizona coronavirus patient showed a deletion of 81 genetic 'letters' that suppresses the virus's ability to fight the human immune system, also seen as SARS began to fade.

Scientific evidence suggests that people who are overweight - which two thirds of adults in the UK are - have a 39 per cent higher risk of dying if they catch the coronavirus.

An interactive map using data from the Office of National Statistics (ONS) has revealed hundreds of towns and villages which have avoided a single Covid-19 fatality during the pandemic.

Researchers at Los Alamos National Laboratory have discovered a mutation to the coronavirus's spike protein that may make it more infectious - and it has spread around the globe.

A new study, led by Tsinghua University. found that recovered coronavirus patients had varying antibodies such as immune cells that stop the virus from attaching to our cells.

Researchers from the University of Sheffield and Los Alamos National Laboratory in New Mexico found that a newer, faster-spreading version of the virus seems to edge out the older type.

The president of the Hospital Consultants and Specialists Association said Britain's testing and tracing has been 'inadequate' and questions should be asked about the timing of lockdown.

Researchers from Germany and the US explained fat cells secrete ACE-2 receptors - known as the 'gateway' into the cells of the body.

Just yesterday University of Sheffield researchers claimed that a new, more infectious type of COVID-19 had been racing through Europe. But the finding was today dismissed as 'unfounded'.

The two party leaders clashed over the pandemic as they faced each other for the first time at Prime Minister's Question in the hushed surroundings of the mostly-empty House of Commons.

SIR CLIVE WOODWARD: It is very seldom I tip against England, if ever, as I just never see them losing at rugby. But I must confess I make France the favourites in Paris.

SIR CLIVE WOODWARD: England have taken Ireland to the cleaners twice in the past 12 months, but only one of those victories counted for a bean and that was in Dublin 12 months ago.

Well, look what we have here… If it isn’t another mid-size SUV crossover for us all to get excited about. Which isn’t difficult – from a styling point at least (after which don’t hold your breath)

The Champions League returned with a bang this week as Borussia Dortmund, Atletico Madrid and RB Leipzig took huge steps towards three big upsets.

Jose Mourinho's extraordinary managerial career has contained many memorable moments on and off the pitch, with the highly-decorated Portuguese not afraid to speak his mind.

Sportsmail looks at whether Chelsea or Tottenham are better equipped to secure a Champions League spot ahead of their meeting at Stamford Bridge on Staurday afteroon.

There was a glint in Pep Guardiola's eye as he talked about Real Madrid, as European football's most influential coach gets ready to tackle its ultimate winning machine.

The Premier League once again treated spectators to twists and turns galore, and here are 10 things we learned from all the action this weekend.

With Tottenham losing 3-2 to Wolves on Sunday in the Premier League and having no out-and-out strikers at his disposal, Mourinho only decided to call on the 18-year-old in injury-time.

Tottenham host Norwich and Sheffield Wednesday play Man City tonight in the FA Cup fifth round. Sportsmail's KIERAN JACKSON will provide live commentary of the action and the quarter-final draw.

What an absolute mess Tottenham Hotspur are in. Jose Mourinho's side have lost four games in a row and are in crisis, but they were in a much worse state before the Portuguese arrived.

Jose Mourinho will have no hesitation about fielding Eric Dier against Burnley on Saturday after making a passionate defence of the Englishman in the wake of his row with a fan.

Pep Guardiola has admitted he didn't expect Manchester City to be so far clear of United when he joined the club - and says recruiting the right type of player has been key to their success.

Spurs boss Jose Mourinho is angry with Tanguy Ndombele, Eric Dier is angry with fans and Spurs players were angry with each other in a heated half-time inquest at Turf Moor on Saturday.

Ahead of Spurs' second-leg against Red Bull Leipzig tonight, an omen Spurs fans won't want to hear: Jose Mourinho has never won a Champions League knockout tie after losing the first-leg at home.

The dark clouds are looming over Tottenham after four defeat in their last five. But victory over RB Leipzig and Champions League progression would be a huge boost.

There was no heart-stopping comeback for Tottenham in Leipzig, no second-half resurrection. They lost away as they did at home, just by more as they tumbled out of the Champions League.

Jose Mourinho came under fire from Rio Ferdinand as he blamed the Tottenham manager for their lackluster performance in Tuesday night's 3-0 defeat against RB Leipzig.

MATT BARLOW IN LEIPZIG: Spurs crashed out of the Champions League with a 4-0 aggregate defeat against RB Leipzig just seven days after they were dumped out of the FA Cup.

MATT BARLOW AT THE RED BULL ARENA: Jose Mourinho's side were beaten 4-0 on aggregate and Alli admitted they lacked 'maturity and 'fight' and that their 'mentality' was not 'strong enough'.

MATT BARLOW AT THE RED BULL ARENA: Jose Mourinho admits his beleaguered Tottenham team faces an uphill struggle to be back in the Champions League next season.

David Ginola believes Mauricio Pochettino was doomed after guiding Tottenham into last year's Champions League final and the club's remarkable run is the reason why Jose Mourinho is struggling.

Former Tottenham boss Mauricio Pochettino has revealed he sent messages to his ex-Spurs players after the Premier League was suspended due to the coronavirus pandemic.

Rio Ferdinand believes Arjen Robben chose a move to Chelsea over Manchester United in part because of the 'smell' of the Carrington training ground.

Tottenham's recruitment team, led by chief scout Steve Hitchen have followed Newcastle by effectively shutting down their scouting department until further notice

Spurs manager Mourinho was forced to admit he was in the wrong after flouting social distancing advice by overseeing a training session with midfielder Tanguy Ndombele in Barnet.

Mourinho was pictured putting Ndombele, Ryan Sessegnon and Davinson Sanchez through a training session on Hadley Common on Tuesday - an episode that has left Ndombele bemused.

From overcoming horrific injuries to coping with overbearing managers, the defender has had several hurdles hurled into his path at Manchester United, but each has been successfully navigated.

Mourinho oversaw a training session with midfielder Tanguy Ndombele on Hadley Common in Barnet earlier this month and was spoken to by unhappy Spurs chiefs.

The right-back was signed by Jose Mourinho from Porto for a fee of £19million in 2018 but he has fallen down the pecking order at Old Trafford.

Mourinho is desperate for reinforcements in both defence and attack and has identified West Ham's Issa Diop and Wolves striker Raul Jimenez as his top two targets.

It's a picture that shows a different time and frankly, one that people nowadays might find hard to imagine; Pep Guardiola and Jose Mourinho, sat side-by-side as friends, wearing crests of the same club.

The French midfielder joined the north London club last summer in a £65million move from Lyon, but has massively failed to deliver on the overwhelming expectation heaped on his shoulders.

WARNING: DISTRESSING CONTENT The male lion was filmed caressing the baby kudu antelope's face with its huge paw and the female licked it in Eastern Cape, South Africa.