Those suffering from mild muscle aches, scratches in the throat and dry cough may be carriers of the 'Omicron' variant, warn British scientists in their statements in the "Independent" newspaper.
They also explain that the clinical picture of the patients who are carriers of the highly contagious variant, differs from that of the patients who carry the "Delta" strain.
According to the British newspaper, before the pandemic of the disease Covid-19, if someone had a runny nose and headache while feeling a sore throat, they might treat it as a simple cold and continue their routine normally.
But how can one be sure that it is a cold and not a coronavirus?
The common cold is caused by a different strain of the virus from Covid-19. But with the highly contagious Omicron variant often causing mild symptoms such as a stuffy nose, sore throat and dry cough, it is very difficult to tell the difference without examination.
Professor Tim Spector of Britain's ZOE Covid app said it was more important than ever to have a Covid test even without symptoms.
For her part, Christina Marriott, CEO of the Royal Society of Public Health (RSPH), said: "Increasingly, people who have received two doses of the vaccine tend to have less severe symptoms, such as headache, runny nose, or sneezing. , sore throat and loss of smell.
"It is important for people who have been fully vaccinated to remain vigilant for cold-like symptoms and to undergo a Covid test if they live or work with people who are at higher risk for the disease."
For Professor Irene Petersen, Professor of Epidemiology at University College London (UCL), "Colds and headaches are symptoms of many infections, but they can also be the first symptoms - and only symptoms - of Covid disease. Therefore, if you have these symptoms, I would recommend using a lateral flow test for a few days.
The Covid Symptoms Study (ZOE), funded by the UK Government, has identified common coronary heart disease symptoms that show slightly differences depending on whether one is vaccinated or not.
Headache
Although headache is a lesser-known symptom of Covid, it is one of the earliest signs, according to the ZOE study.
In addition, it is a more common symptom than the classic (symptoms) of cough, fever and loss of smell.
The study found that Covid headache, which tends to be moderate to severely painful, occurs on both sides of the head rather than in one area, can last more than three days and tends to be resistant to common painkillers.
Catarrh
Last winter, the ZOE study found that runny nose was the second most commonly reported symptom after headaches, with nearly 60% of those who tested positive for Covid with loss of smell also reporting a runny nose.
Sneeze
The ZOE study found that sneezing more than usual could be a sign of Covid in people who have been vaccinated, although it does suggest that sneezing is much more likely to be a sign of a cold or allergy.
Sore throat
Many people with Covid complain of having a sore throat that is similar to what a person may experience when they have a cold or laryngitis.
The sore throat associated with Covid disease tends to be mild and lasts no more than five days, so a very sore sore throat that lasts longer may be something else.
According to the ZOE study, almost half of those with Covid report a sore throat, although this is more common in adults aged 18-65 than in the elderly or under 18.
Loss of smell
It remains the strongest indicator of Covid infection, regardless of an individual's age, sex, or severity of illness.
While sufferers may not lose their sense of smell completely, it may change, and they may not be able to smell things with a strong aroma.
The sense of taste can also be affected.
Persistent cough
Persistent cough is widely accepted to be one of the three main symptoms of Covid, but according to the ZOE study, only about four in 10 patients will develop it.
In this context, "persistent" means coughing several times a day, "for half a day or more".
The cough associated with Covid disease is usually whooping cough. A persistent cough tends to appear about a few days after the illness and usually lasts for about four or five days.
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