From a dry cough to a loss of sense of smell, a number of unpleasant symptoms are known to be associated with Covid-19.
Now, researchers from King’s College London have warned of several ‘surprising’ symptoms that could be early warning signs for the virus.
Using data from the COVID Symptom Study app, the researchers have created a list of the most common symptoms reported by patients in the first seven days after onset.
The researchers explained: “We have been busy researching what the early symptoms of COVID-19 really are, as this information is essential to helping us all stop the spread of the virus in the coming months.
“If we can spot cases based on symptoms sooner, people will be able to start self isolating in those first few days and stop the accidental spread of the virus.”
Two of the most surprising early warning signs revealed in the study are headache and fatigue, which the researchers describe as the ‘dark horses of Covid symptoms’.
The researchers said: “Our data shows that the most commonly experienced early symptoms are actually headache (82%) and fatigue (72%) – and this is the case for all age groups.
“Only 9% of COVID-positive adults aged 18 – 65 didn’t experience headache or fatigue.”
Despite these high levels, only 1% of people reporting fatigue and/or headache on the app ended up testing positive for Covid.
The researchers added: “While headache and fatigue are commonly found in people who have COVID (alongside other symptoms), having either or both of those symptoms alone is unlikely to be indicative of COVID.”
Unsurprisingly, a fever, persistent cough and loss of smell were found to be strong early indicators of Covid-19.
The researchers said: “40% of all age groups reported having a fever in the first seven days, and this or loss of smell and persistent cough are still the key symptoms to be aware of – so people with the classic three symptoms of persistent cough, fever or loss of smell should certainly seek a COVID test.”
Meanwhile, people over 65 were also found to report being confused, disorientated and having severe shortness of breath in the early stages of infection.
The researchers continue to monitor the app, and will release new findings soon.
They added: “Please bear in mind that we are providing percentages and averages and in medicine there may be rare exceptions.”