Jacob Rees-Mogg is self-isolating after one of his children developed coronavirus symptoms.
Deputy chief whip Stuart Andrew stood in for the Commons Leader at business questions on Thursday.
Rees-Mogg recently tweeted a photo of some of his children as schools reopened for pupils.
Valerie Vaz, Labour’s shadow Commons leader, said: “We all wish the Leader of the House and the whole Rees-Mogg family well.”
It comes a day after Boris Johnson imposed new lockdown measures on the country in a bid to halt a recent surge in cases.
The prime minister urged people to limit their social contact “as much as possible” as he confirmed that social gatherings of more than six people will be outlawed in England from Monday.
Meanwhile Professor Neil Ferguson, whose modelling led to the decision to impose the lockdown in March, said people should “hesitate” at the “headlong rush to get everybody back into offices” amid the rising cases.
“The case number increases we’ve seen in the last two weeks do not yet account for the reopening of schools. So undoubtedly that may increase transmission still further and there may be a need therefore to reduce contacts in other settings,” he told Today.