The Brazil variant of Covid shares the key symptoms with the initial strain - a high temperature, continuous cough and loss of sense of taste or smell.
First detected in the city of Manaus in December, the Brazil variant has been in the UK for a few weeks, health officials confirmed on Sunday.
The variant shares the now well known key symptoms - but people can still be asymptomatic no matter the strain.
"And there is no single symptom that means that you definitely do or don’t have the virus.
"So, if you have any concerns that you may have coronavirus, the safest thing to do is self-isolate and get a test.
"The new strains of coronavirus share the same key symptoms with the initial strain – including a high temperature, continuous cough, and loss of sense of taste or smell."
Have you experienced any extreme symptoms of the Brazil Covid variant? Email email@example.com
The BHF reported that early research into the UK (Kent) strain shows the symptoms are very similar to other strains.
The research, based on testing in England, reports 35% of people who tested positive for the UK variant as having a cough, compared to 27% who tested positive for other strains.
These levels of symptoms are similar to the levels seen with other strains.
Loss of taste or loss of sense of smell is slightly less common for people with the new UK strain - as 15% of people with the UK strain report either of these symptoms, compared to 18% of people with other strains, the BHF said.
There have been up to six cases of the Manaus variant in the UK so far - three detected in England and three in north-east Scotland.
It is understood that officials became aware of the English cases on Friday and the Scottish ones on Saturday.
One of the cases in England has not been located and could by anywhere in the nation after the person did not complete their registration card.
Yvette Cooper, home affairs select committee chair, said stronger action was needed by the Government to prevent other more dangerous variants arriving in the UK.
"We need to look at how these cases have arrived in the country in the first place in order to prevent others doing so," she said, speaking on the Today programme.
"These cases seem to have arrived a month after the Brazil variant was first identified and we were raising with the Government the need for stronger action."
Ms Cooper said many travellers would have taken "indirect flights" from Brazil and that the situation highlighted "gaps" in the system.
"There is a concern that the Government is raising expectations about summer holidays that they may not be able to meet," she said.
A hunt is under way to locate one of the first people in the UK believed to have contracted the Manaus variant of coronavirus, a new strain that may spread more rapidly and respond less well to existing vaccines.
Anyone who took a test on February 12 or 13 and has not received a result, or has an uncompleted test registration card, is being asked to come forward immediately, as health officials scramble to track down the individual.
Critics said the development exposed the "weaknesses" in the border protections against new strains and condemned the Government for delaying toughening restrictions.
The Gloucestershire cluster was said to originate from one individual who travelled back from Brazil and arrived in London on February 10 - five days before the Government's quarantine hotel policy came into force.
The traveller isolated at home with the rest of their household under the rules in place at the time. One member exhibited Covid symptoms before getting a test.
It is understood there were four positive tests in total in that household, two of which were confirmed with genetic sequencing to be the P.1 variant.
But officials are awaiting the results of sequencing on the outstanding two tests to see if they were infected by the Manaus strain.Follow the Official Rokna NEWS Telegram Channel For More and fresh NEWS.