NHS chiefs are worried pressures on the NHS may deter people coming forward with symptoms.
It's the most significant drop since the Omicron wave hit the country in December, the figures suggest.
South African scientists say their research was not taken more seriously because it was from Africa.
Other groups have reported higher protection, but the results are still seen as a triumph.
A question everyone's asking: what's my Covid risk? Here's how to find out.
Borrowing - which hit a record £22.3bn in October - cannot go on indefinitely, chancellor says.