Covid experts have said the new Omicron variant may cause different symptoms than the original strain of coronavirus.
Health chiefs believe Omicron for most people only causes “mild illness” but scientists across the world are in a hurry to discover new information about the fresh strain.
First discovered in South Africa, Omicron is spreading faster than the covid-19 with worries growing about the strain circumventing vaccines or causing more serious side affects.
People who are testing positive for the new strain are presenting symptoms such as a headache, runny nose, sore throat and sneezing.
A World Health Organisation (WHO) official has told the Reuters news agency that most people are not getting seriously ill, although it could still be the case.
Dr Maria Van Kerkhove, a top WHO adviser, said: “In terms of the severity profile, we have seen reports of cases with Omicron that go from mild disease all the way to severe disease.
“There is some indication that some of the patients are presenting with mild disease, but again it is early days. We do have a surveillance bias right now in terms of the cases that are being detected.
“There is also a suggestion of increased hospitalisations across South Africa, but that could be the sheer fact that we have more cases.
“If you have more cases you will have more hospitalisations.”
Dr Angelique Coetzee, chair of the South African Medical Association, said the main symptoms of Omicron to look out for are:
She described one “very interesting case” of a six-year-old girl who had “a temperature and a very high pulse rate”.
Meanwhile, a health director in Botswana said 16 out of 19 people infected had no symptoms, while the other three had “very, very mild” illness, according to Mirror Online.
It comes as nine more cases of the Omicron variant were discovered in England taking the total across the country to 22.
Cases have now been identified in the East Midlands, East of England, London, South East and North West.
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A further case has been identified in Scotland, bringing the total to 10.