Number 10 has been forced to clarify after Boris Johnson suggested that the government would be able to track the rate of coronavirus by testing the water supply.
Speaking in the House of Commons the Prime Minister spoke about strengthening lockdown measures in a particular area due to a local "flare up".
But his comments about detecting the deadly virus "in the water supply" confused and scared many.
His aides rushed to insist that he was referring to waste water rather than the fresh water coming out of people's taps.
Mr Johnson told MPs: "The intention is that the covid alert system in time will be sufficiently sensitive and flexible so as to detect local flare ups, so that if for example the Covid is detected in the water supply of a certain town or whatever then steps can be taken, or in a school or whatever then, steps can be taken on the spot to deal with that flare up, to keep the R down locally as well as nationally."
But later the Prime Minister's spokesman was forced to clarify.
He insisted Mr Johnson was referring to sewage or waste water rather than the water that comes out of the tap and most people drink.
“That specifically is a reference to sewage or waste water as it’s more politely described.
"Some studies have been carried out overseas on this and I think it is something we are looking at as a possible way of seeing if you could track the rate of infections locally.”
Former Labour MP Anna Turley tweeted: "The man is a dangerous liability".
