The UK's Covid R rate has fallen from to 0.9 to 1.1 from 1.1 to 1.3 in the last seven days, latest figures show.
The UK Health Security Agency said the drop suggests the epidemic might be shrinking.
An R number between 0.9 and 1.1 means that for every 10 people infected, they will on average infect between 9 and 11 other people.
Last week's R-rate was estimated between 1.1 and 1.3.
The last time the R-rate stood at 0.9 was two weeks ago.
The news comes as more than 1.1 million people in private households in England tested positive for Covid-19 last week as cases levelled with the height of second wave in January.
Weekly data from the Office for National Statistics found one in 50 people were infected in the week ending October 30.
The estimate, which is unchanged from last week, was the same at the peak of the second wave in early January.
It marks a rise from the week up to October 16, when 977,900 people were infected by the virus - or one in 55.
Modelling shows rates have increased among young people from year 12 to 24-year-olds and for those aged 50 to 69.
Rates have decreased in year 7 to 11 pupils but the percentage of people testing positive in this age group remains high, at 7.5%.
In Wales, around one in 40 people had the virus during this period, while in Northern Ireland it was one in 65.
Scotland reported the lowest rate with one in 80 people estimated to be infected.
Covid rates have increased in Northern Ireland but trends remain uncertain across the rest of the UK, according to the ONS.
Boris Johnson has so far resisted pressure to impose fresh Covid restrictions despite cases remaining at a worrying level.
The Government has repeatedly said that there is nothing in the data to suggest a need to move to its "Plan B", which would see a return to mandatory mask use, vaccine passports and orders to work from home.
