A TV doctor says ‘we are hopefully turning the tide on the virus’ after experts revealed vaccines are able to control the Covid-19 pandemic, as they are likely to cut transmission.

Just one dose of either the Pfizer/BioNTech or AstraZeneca vaccines leads to a two-thirds drop in coronavirus cases and is 74 per cent effective against symptomatic infection.

After two doses of Pfizer, there was a 70 per cent reduction in all cases and a 90 per cent drop in symptomatic cases - these are the people who are most likely to transmit coronavirus to others.

Experts are still collecting data on two doses of AstraZeneca but say their findings show that both vaccines work and are effective in the real world.

One of the new studies, which has yet to be peer-reviewed, is based on data from the national Covid-19 Infection Survey run by the University of Oxford and the Office for National Statistics (ONS).

It included a random sample of more than 373,000 adults from across the UK, who produced more than 1.6 million swab test results between December and April.

Professor Sarah Walker, from the University of Oxford and chief investigator for the survey, said the study suggested vaccines could reduce transmission and were also effective against the Kent variant of coronavirus.

She said: "Showing that the benefits are greater both for people with high viral load and for people with symptoms, both of whom have probably got the greatest chance of onward transmission, was really not necessarily something I was expecting and... I was pleasantly surprised."

The data showed a 57 per cent drop in infections among people not experiencing symptoms after one vaccine dose.

Speaking on Good Morning Britain today about the study, Dr Amir Khan says the vaccine are helping to reduce the rate of infection.

He said: “It is a very bold statement from Professor Sarah Walker, chief investigator of this study.

“It took 1.6million swabs from people across the UK over the last few months and compared swabs from people who have been vaccinated, who haven’t yet.

“Even having one dose of vaccine reduces your risk of having the virus, getting symptoms, reduces the risk of symptomatic infection by 74 per cent, “Importantly, it can reduce your risk of having no symptoms and carrying the virus by over 50 per cent. These people would otherwise be wandering around, spreading it around.

“The vaccines reduce that risk. People that did test positive for virus, who had vaccine, had much lower viral loads; less risk of transmission.

“That is what she is referring to. We are hopefully turning the tide on the virus and reducing this rate of transmission.”