The UK is feared to be in the midst of another Covid wave as hospital admissions have jumped almost double in a week.
Latest figures show the number of patients testing positive for coronavirus is up 48%, compared to seven days ago.
Fears have already been raised among the medical community the approaching colder weather could boost numbers.
Now, a total of 7,024 people with coronavirus were in hospital as of 8am on September 28, according to NHS England.
The number is half the 14,000 in mid-July at the peak of the wave of infections caused by the Omicron BA.4 and BA.5 subvariants of the virus.
It comes as recent data from the ZOE Health Study suggested an average of one in 32 people in the UK were likely to have symptomatic Covid-19 at the start of this week.
Professor Tim Spector, co-founder of the ZOE study, said: “It's clear we're now seeing an autumn wave of Covid-19, combined with increases in hospital admissions.
"With rates on the rise, especially in the vulnerable elderly age groups, the impact on hospitalisations could be higher.
"However, the youngest age group are showing possible early signs of case numbers slowing.
“Children tend to be a leader of infection trends, so if this continues next week it is possible that the Covid wave might not be as bad as previously predicted."
Earlier this week, the UK Health Safety Authority (UKHSA) urged the 30million people eligible for a free flu and Covid booster to take it up to avoid overpowering the NHS.
Dr Susan Hopkins, chief medical advisor at UKHSA, said: “Flu and COVID-19 are unpredictable but there are strong indications we could be facing the threat of widely circulating flu, lower levels of natural immunity due to less exposure over the last three winters and an increase in COVID-19 circulating with lots of variants that can evade the immune response.
“This combination poses a serious risk to our health, particularly those in high-risk groups.
“The H3N2 flu strain can cause particularly severe illness.
"If you are elderly or vulnerable because of other conditions you are at greater risk, so getting the flu jab is a sensible, potentially life-saving thing to do.
“We are extremely fortunate to have vaccines against these two diseases. Most eligible groups have been selected because they are at higher risk of severe illness.
“Younger children are unlikely to have built up any natural immunity to flu and therefore it is particularly important they take the nasal spray vaccine this year.
“So, if you are offered a jab, please come forward to protect yourself and help reduce the burden on our health services.”
More vaccination centres are expected to be made available this year to boost the efforts.
