An expert in virology has said the rising rates of Strep-related infections like scarlet fever may be a knock-on effect from Covid lockdowns.

Paul Hunter, from the University of East Anglia, put the increase in cases down to a lack of exposure to infections while measures were in place to control the spread of coronavirus.

This meant that people had not built up as much immunity as in previous years.

He said that cases of Strep-related infections tended to follow a similar pattern to influenza cases.

Prof Hunter said: "The last big surge in scarlet fever cases was in 2018 - a week or so after the last big surge of influenza in 2017-18.

"To that extent, it is not really surprising to see the rise we are now.

"The peak of Group A Strep and scarlet fever do tend to follow the flu - we had it in 2010/11 and in 2017/18, now we are seeing it in 2022."

He added: "Over the past two years, flu, along with Covid, has been suppressed.

"This does not necessarily mean to say that if we had not had lockdowns we would be seeing less flu at Group A Strep now. That is a difficult thing to work out.

"However, cases are increasing earlier in the year than they have done previously, and at a quicker rate."

Prof Hunter said that if infections like these are suppressed for a long time, people do not naturally pick up the same level of immunity they ordinarily would have - which could explain growing cases.

"This is why I perhaps would not have had infection control measures in place quite as long as they were. I did not necessarily think they were needed beyond June or July 2021 for this precise reason," he added.

However, he added that it was difficult to say at this stage what would happen next.

He said: "At the moment it is around where we would normally be, but it is not easy to say whether they will continue to rise or if they are going to plateau."