Measures in the Government’s “Plan B” for tackling coronavirus may not be needed if data continues to show a decline in cases, a leading scientist has suggested.
Prof Ferguson said: “At the moment we don’t actually have any growth in case numbers but we have continued growth in hospitalisations, but at a relatively slow rate.
“At the end of the day, it’s a political decision about what the NHS can cope with, but we’re not in the same position we were, for instance, a year ago with very rapidly increasing hospitalisations.
“So in some sense, there is some time to see whether the apparent drops in case numbers now being seen are sustained, in which case such measures shouldn’t be necessary.”
Asked if cases have peaked, he added: “I think it’s too early to say we have reached a peak.
“Maybe because this week is half-term week, and so we know lots of people have gone on holiday, testing patterns are different than usual.
“We will have to wait probably at least another couple of weeks if not closer to three to be sure.
“But there are some encouraging signs in terms of the dip in case numbers.
“If it isn’t peaking now then most of the modelling, Sage modelling out there, would suggest it should peak so long as we keep getting boosters into people’s arms and achieve a reasonably high – 90% or so coverage – of boosters.
“Then we should start to see a sustained decline in the coming weeks, but there is a lot of uncertainty in the modelling.”
It comes as a study suggests that vaccinated people who then catch Covid-19 are infectious for less time than those who have not been jabbed.
Those who are jabbed are much more likely to experience mild illness than those who are unvaccinated, while the people they live with are less likely to catch it if they have vaccines themselves.
The new study of 621 people in the UK with mild Covid-19 found coronavirus vaccines lower the risk of infection, but the virus can still be transmitted in the household.
However, a quarter of vaccinated people living with someone with Covid subsequently tested positive, compared with 38% of those who were unvaccinated.
Researchers said this demonstrates that unvaccinated people cannot rely on the immunity of those who have been jabbed for protection.
The new study also found that those who did get the disease despite being vaccinated were as infectious as those who had not been jabbed.
However, those who had been vaccinated were as infectious for less time, the data indicates.
In other words, infections in vaccinated people cleared more quickly than those in unvaccinated people, but resulted in a similar peak viral load.
The researchers suggested this is probably why the Delta variant is able to spread despite vaccination.
They urged unvaccinated people to get vaccinated to protect themselves from severe disease and those eligible for a booster to receive it as soon as offered.
Prof Ferguson said any waning in protection from vaccines is a gradual process, adding the current six months between second and third doses is “arbitrary”.
He added: “It was chosen because most of the early data from Israel on the effect of boosters involved that level of delay just because of the very early timing of their vaccination programme and when they started implementing boosters.
“But there’s nothing biologically to make us think the boosters will be any less effective if given after four months, so it really is for the Joint Committee on Vaccination and Immunisation (JCVI) to consider the data and the Government to consider whether they want to accelerate the booster programme.”
Professor Ajit Lalvani of Imperial College London, who co-led the study, said: “We found that susceptibility to infection increased already within a few months after the second vaccine dose – so those eligible for Covid-19 booster shots should get them promptly.”
Researchers suggest that to reduce the risk of transmission at home, people should continue to use measures such as regularly washing their hands, throwing tissues away and washing their hands after use.
The new study was published in The Lancet Infectious Diseases.