Labour MP for Jarrow Kate Osborne said she has been diagnosed with coronavirus following a period of self-isolation and subsequent testing.
Writing on Twitter, Osborne added: “I will continue to self isolate until I have fought off the illness, but in the mean time I would encourage everyone to band together and support the most vulnerable in our communities.
“The NHS are urging people to stay at home for 7 days if you have either a high temperature or a new, continuous cough.
If you are displaying any symptoms yourself, please self isolate and visit http://111.NHS.UK or call 111 for advice.”
Osborne is the second MP confirmed to have contracted the virus, after health minister Nadine Dorries.
Boris Johnson is to address the nation on the coronavirus threat after meeting ministers and officials to consider measures including banning mass gatherings and lengthy household isolation for the elderly.
The prime minister will chair an emergency meeting of the Cobra committee on Monday afternoon before holding the first of the daily press conferences being planned to update the public on Covid-19.
It comes as The Guardian reported on a Public Health England (PHE) briefing which warned health chiefs the epidemic in the UK could last until spring next year and could lead up to 7.9 million people being admitted to hospital.
As the UK death toll reached 35 on Sunday, health secretary Matt Hancock said over-70s could be told to stay at home for up to four months within the “coming weeks”.
Several MPs have also decided to self-isolate after experiencing symptoms, including Labour MP Bell Ribeiro-Addy.
There have been a total of 1,543 positive tests for coronavirus in the UK as of 9am on Monday, up from 1,372 at the same time on Sunday, the Department of Health said on Monday afternoon.
Officials said 44,105 people have been tested in the UK, of which 42,562 were confirmed negative and 1,543 were confirmed as positive.