Do I have Omicron, cold or flu symptoms? How you can tell the difference

Experts say the Omicron variant may lead to mild symptoms, making it harder than ever to distinguish between the infections

A man receives a fourth dose of the coronavirus disease vaccine after Israel's Health Ministry approved a second booster for the immunocompromised at Sheba Medical Centre in Ramat Gan, Israel. Reuters

A health worker inoculates a boy at a vaccination centre in Bogota, Colombia. AFP

Expo 2020 Dubai visitors are still arriving to enjoy the world's fair, where safety measures have been put in place to protect against the Omicron variant. Victor Besa / The National

A cleaner uses sanitiser around Al Wasl Plaza at Expo. Victor Besa / The National

A Covid-19 rapid test centre in Athens. AP

French Health Minister Olivier Veran gives a speech to parliament during a debate on a bill to bring in a compulsory vaccine pass. EPA

A girl crying just after she received her Covid-19 shot in Mumbai is comforted. India has begun vaccinating those aged 15 to 18. AP

A man is vaccinated in Dhaka, Bangladesh, where there are fears the Omicron variant may cause a major rise in Covid-19 cases. EPA

Pupils show their vaccination certificates during an inoculation drive in Jakarta, Indonesia. EPA

Perched on his father's shoulders, a boy joins masked Japanese workers as they queue to offer prayers on the first business day of the year at the Kanda Myojin shrine Tokyo. Getty

A patient is delivered to Mount Sinai Hospital in Toronto amid fears of a wave of coronavirus cases in Canada. Reuters

A teacher takes a pupil's temperature as face-to-face classes return in Mexico City. EPA

Medics take part in a vaccination session day in Panama City. EPA

Logan International Airport in Boston, where there have been cancellations and disruption owing to bad weather and Omicron. Reuters

Volunteers hand out Covid-19 lateral flow tests provided by the British government in London. AFP

At the New York Stock Exchange, markets were up slightly on the first morning of trading in the new year as Omicron cases begin to subside in South Africa. AFP

People wait in line for a Covid-19 test in Los Angeles. AP

A person receives a Covid-19 test in New York City. The US recorded more than a million cases on January 3 as the Omicron variant continued to spread. AFP

Mascots walk past a sign for Covid-19 tests in New York City. AFP

A nurse waits for a blood sample analysis in the Covid-19 intensive care unit at La Timone Hospital in Marseille, southern France. AP

Suzanne, 5, is tested for Covid-19 in Albigny-sur-Saone, outside Lyon in central France. AP

Students in Tokyo wearing masks take part in an annual New Year calligraphy contest. Last year's event was cancelled because of the pandemic. Reuters

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Do you have a sore throat, runny nose, body ache or fever? It could be a common cold, the flu or Covid-19 as the symptoms are very similar.

People suffering from these symptoms may wonder if they have Covid-19 and should isolate and take a test.

But they may also be tempted to think it is just a cold.

With the Northern Hemisphere in the middle of its winter, when influenza cases tend to peak (the season runs from early October to mid-May), flu may be suspected too.

Given that the Omicron coronavirus variant may be more likely to lead to mild symptoms, people may feel it is harder than ever to distinguish between the various respiratory infections going around.

Here we take a look at the issue and ask experts for advice.

Does Omicron cause the same symptoms as the common cold?

Based on symptoms alone, it may be difficult to tell apart the common cold and Covid-19, especially when it is caused by the Omicron variant.

This shows the importance of testing.

“A common cold and Omicron is, in my view, impossible to distinguish,” Prof Eskild Petersen of Aarhus University Hospital in Denmark, who chairs the European Society of Clinical Microbiology and Infectious Diseases, told The National.

It is a point echoed by Dr Andrew Freedman, an infectious diseases specialist at Cardiff University in the UK.

“A lot of people, particularly vaccinated people, are getting what would otherwise be thought of as the common cold,” he said.

The UK’s National Health Service said that the main symptoms of Covid-19 include a high body temperature, a new, continuous cough and loss or change to the sense of taste or smell.

Some of these overlap with common cold symptoms, which may also include a blocked or runny nose, muscle aches and sneezing.

Will Sars-CoV-2 become another coronavirus that causes the common cold?

Some researchers have forecast that Sars-CoV-2, the coronavirus that causes Covid-19, will eventually largely cause only cold symptoms.

Four other coronaviruses that infect people do in fact cause the common cold. One of these four is called HCoV-OC43.

Researchers have proposed that OC43 may have been responsible for the “Russian flu” pandemic that began in 1889 and went on to kill about one million people.

While OC43 can still cause severe illness in certain groups, such as infants, the elderly and people with a weakened immune system, it usually causes simply a cold.

This may be because we are infected with it periodically, so have a background level of immunity.

Sars-CoV-2 may be moving in the same direction, given that the Omicron variant, while highly transmissible, appears to often cause milder symptoms.

There is also now wider immunity to the virus thanks to vaccination and previous infection.

Can influenza and Covid-19 be told apart?

While distinguishing between the common cold and a mild case of Covid-19 is difficult based on symptoms alone, infectious diseases experts said flu is more likely to produce different indicators.

“Flu can be a more severe illness with aches and pains,” said Dr Freedman.

In particular, influenza may cause a person to develop muscle pain and back pain, said Prof Petersen, symptoms that are not typically associated with Covid-19, especially when it is caused by the Omicron variant.

“If you really have influenza, you have fever and general muscle pain,” he said, adding that a loss of smell – sometimes seen with Covid-19 – is typically not found with flu.

As well as an aching body, the NHS said that flu symptoms, which may arise rapidly, can include a sudden increase in body temperature (38°C and above), feeling tired or exhausted, a dry cough, a sore throat and a headache, among others.

What should people do if they have symptoms that could be Covid-19?

Rules vary from country to country, but as a general piece of advice, experts say people with possible Covid-19 symptoms should self-isolate and get tested, ideally with a PCR test as these are more accurate.

A key point emphasised by health organisations such as the US Centres for Disease Control and Prevention (CDC) is that people infected with the coronavirus can pass the pathogen on even when they have mild or no symptoms.

“CDC expects that anyone with Omicron infection can spread the virus to others, even if they are vaccinated or don’t have symptoms,” the organisation said in an online briefing last month.

Vaccination remains widely recommended as a way of reducing the chance of admission to hospital, severe illness and death, although people with Covid-19 symptoms should not be vaccinated until they recover, the NHS advises.

It said people should wait 28 days after a positive test or after symptoms started before getting inoculated.

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