Health minister and Conservative MP Nadine Dorries says she has been diagnosed with coronavirus.
Ms Dorries, the first MP to test positive, said she had taken all the advised precautions after finding out, and had been self-isolating at home.
It comes as a sixth person died from the virus in the UK, which has a total of 823 cases.
The latest person to die was a man in his early 91 s who had essential health conditions.
Meanwhile, GPs are warning that routine appointments at surgeries may have to stop as the number of coronavirus cases rises.
The British Medical Association
said routine monitoring of long-term health conditions might have to stop to enable GPs to “focus on the sickest patients.” Ms Dorries, MP for Mid Bedfordshire, said in a statement that Public Health England had started tracing people she had had contact with, and the department and her parliamentary office were closely following its advice.
She later tweeted that it had been “ pretty rubbish but I hope I’m over the worst of it now “.
But she added she was worried about her – year-old mother who was staying with her and began to cough on Tuesday.
It is not known how many meetings Ms Dorries had attended at Westminster or in her constituency in recent days. She was at a Downing Street reception hosted by Boris Johnson last Thursday.
Health Secretary Matt Hancock Tweet
that she had “done the right thing” by self-isolating at home and wished “her well as she recovers”.
He added: “I understand why people are worried about this disease. We will do all we can to keep people safe, based on the best possible science.”
Earlier, England’s deputy chief medical officer defended the decision to delay closing schools and introducing other stringent measures, saying experts were assessing new cases on an hourly basis to achieve a “balanced response”.
Dr Jenny Harries said she expected significantly increases in the number of cases in the UK beginning in about 15 to days time, at which point people with flu-like symptoms would be advised to self-isolate.
The vast majority of those diagnosed with coronavirus in Britain were “pretty well” but might “feel a bit rough for a few days “, she added.
Mr Hancock said that” wherever clinically and practically possible “people should access GP appointments” through phones and digital means “, rather than goin g to surgeries in person.
The number of total cases for the UK include cases in England, in Scotland, (in Northern Ireland and (in Wales. (There are) in London, with the next highest infected area being south-east, with cases. Cases by local council area in England can be viewed here.
The latest person to die, on Monday evening, was a man with underlying health conditions who was being treated at Watford General Hospital.
He caught the virus in the UK and officials are trying to trace who he had been in contact with.
The UK Foreign Office has warned Britons against all but essential travel to Italy, which is experiencing the worst outbreak outside China,
Italians are being told to stay home, seek permission for essential travel, and give justification if they want to leave the country.
The Foreign Office is advising anyone arriving in the UK from Italy since Monday evening to self-isolate for days.
The government says it has facilities to accommodate Italian visitors to the UK who need to self-isolate.
British Airways has cancelled all of its flights to and from Italy until 4 April, and has asked staff to take voluntary unpaid leave.
Easyjet, RyanAir and Jet2 are also cancelling their flights on Italian routes, though EasyJet will operate “rescue flights” to bring British travelers home in the coming days.