One of the most challenging elements posed by coronavirus has been identifying the most important symptoms.
The UK lists the three main symptoms of COVID as a high fever/temperature, a new, continuous cough and a loss or change to sense of smell and/or taste.
Elsewhere, however, advice is different. The World Health Organization (WHO) lists the three main symptoms as fever, a dry cough and tiredness. It also lists a further seven "less common" symptoms, including headache, sore throat and loss of taste or smell.
Now the Channel Island of Jersey, which is part of the British Isles, has added three COVID symptoms to its existing list of "accompanying" ones to look out for.
The three new symptoms are:
The three new accompanying symptoms join headaches, tiredness, muscle aches, sore throat and gastrointestinal issues (vomiting and diarrhoea) – bringing the island's list in line with the WHO's recommedations.
The island's deputy medical officer of health Dr Ivan Muscat said it is “rare” for COVID to occur without one of the three main symptoms and reassured parents that as the new symptoms are common in young children, they “may not be indicative of COVID”.
In the UK, the NHS does not list any "less common" symptoms for people to be wary of.
It comes as other studies have also thrown new symptoms into the mix of what to look out for when suspecting someone may have coronavirus.
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A study of more than 1 million people in England found that chills, a loss of appetite, headaches and muscle aches are possible signs of having COVID-19.
The research is based on swab tests and questionnaires collected between June 2020 and January 2021 as part of the Imperial College London-led React study.
Having any of the other symptoms or the "classic" ones, either alone or in combination, was associated with infection with COVID, and the more symptoms people showed, the more likely they were to test positive.
Doctors have also called on the government to add cold and flu symptoms to the UK’s official list of coronavirus symptoms.
More than 140 GPs signed an open letter to England’s chief medical officer Professor Chris Whitty asking the UK to bring its official COVID symptoms in line with the WHO.
The letter, published in the British Medical Journal, said a runny nose, a sore throat and a headache should be added to the UK’s official list.
The WHO says “less common symptoms” are aches and pains, sore throat, diarrhoea, conjunctivitis, headache, loss of taste or smell and a rash on skin or discolouration of fingers or toes.
Under its “serious symptoms”, it lists: difficulty breathing or shortness of breath; chest pain or pressure and loss of speech or movement.
Meanwhile the COVID Symptom Study, a joint project between King's College London, Guy's and St Thomas' Hospitals and health technology company Zoe Global, says there are at least six distinct clusters of coronavirus symptoms.
Via data shared through the Zoe app from millions of people in the UK, it found that headache and fatigue are among the most common early symptoms of coronavirus.
It said sore throat, loss of appetite and shortness of breath are also commonly reported.
In older people, delirium is a common symptom, the study said, while rashes are seen in about 8% of COVID infections.
In some cases, it said, less typical symptoms such as rashes or delirium are the only ones experienced.
Additional reporting by Ross McGuinness
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