If you start showing symptoms of Covid-19, the disease caused by the novel coronavirus, the government advice is clear: you have to self-isolate for seven days if you live alone or if someone else in your household shows symptoms, the entire household must isolate for 14 days.
But when WhatsApp rumours spread like wildfire, and clearing your throat has people running out of the room, it can be hard to recognise what is a symptom and what isn’t. Here’s what you need to know about the symptoms of Covid-19.
The most common symptoms of Covid-19 are a persistent dry cough and a fever. The government has advised anyone with these symptoms to self isolate. But they won’t happen for everybody who gets the virus. In a report from the World Health Organisation (WHO) based on 55,924 laboratory confirmed cases of Covid-19, 87.9 per cent of cases had a fever, 67.7 per cent had a dry cough and 38.1 per cent had fatigue. Just over a third of people experienced sput production – coughing up phlegm. Shortness of breath has been a widely recognised Covid-19 symptom, though according to this research only 18.6 per cent of patients experienced it. 13.6 per cent of cases had a headache.
In an interview with BBC Scotland, a man suffering with Covid-19 said the biggest symptom for him was aches and pains in his legs – around 14.8 per cent of Covid-19 cases present with joint or muscle pain, also known as arthralgia or myalgia.
“Coronavirus is nasty in particular, as it attempts to attack the lung tissue, rather than the tissues inside the top of your nose and sinuses where you normally get a cold,” says Lucy Reynolds at the London School of Hygiene and Tropical Medicine. As it attacks the tissue, your body triggers an inflammatory response. However this can sometimes go overboard and the body starts attacking itself, causing some of the more severe Covid-19 cases. One in six people who get Covid-19 will become seriously ill and have difficulty breathing, according to the WHO.
For milder cases, symptoms can improve in under 14 days, though the incubation period – the time between exposure to the virus and the first symptoms appearing – can be anywhere from one to 14 days. That is why someone whose family member has had symptoms must self isolate for 14 days, to make sure they are no longer contagious before potentially exposing more people to the virus.
There are also the less common symptoms. In the same WHO report, it emerges that in a small number of cases, Covid-19 could cause gastrointestinal issues, with five per cent of the cases studied experiencing nausea or vomiting, and 3.7 per cent experiencing diarrhoea. A study published in the journal Gut said that diarrhoea may be underestimated as a symptom and clinicians should be aware of patients complaining of diarrhoea to avoid the infection of healthcare workers.
On March 12, ENT UK, the professional body representing ear, nose and throat surgery in the UK, published guidance saying that there is growing evidence that significant numbers of patients with proven Covid-19 infection have experienced a loss of smell. In Germany at University Hospital Bonn, clinicians surveyed 100 patients with Covid-19 and found that two thirds were experiencing a loss of smell and taste.
This is a very small group, so further study is needed, but it doesn’t surprise Nirmal Kumar, president of ENT UK as the olfactory tissue in the roof of the nose is so delicate, it can easily get damaged. “The interesting thing in this case is that the symptoms of the virus in some people are so minimal,” he says. “It affects the nose, the sense of smell organs but often they don't have anything else.”
Kumar says the loss of smell won’t be permanent for most sufferers, but it is key that organisations recognise it as a symptom so that those affected by this symptom are aware that they could have Covid-19.
But many people will experience no symptoms at all. One study published in the journal Science estimated that around 86 per cent of cases could go undocumented as they have little to no symptoms. Researchers analysed the spread of the virus in 375 Chinese cities between January 10 and January 23 when containment measures were put in place. Another study published in the journal Eurosurveillance looked at passengers on the quarantined cruise ship Diamond Princess, and estimated that the proportion of asymptomatic cases was 17.9 per cent.
For this reason an app has been designed by researchers from King’s College and Guys and St Thomas’ Hospitals for the public to track their symptoms, whether they believe they have the virus or not. The Covid Symptom Checker collects data on how fast the virus is spreading and where are the most high risk areas in the UK, as currently with limited testing capabilities we are unable to see what the prevalence is.
For those who do have symptoms there is the question of when to seek medical assistance. Gregory Poland, director of the Vaccine Research Group at the Mayo Clinic, an academic medical centre, says that if you have a high fever that won’t go down, are having trouble breathing, or are becoming at risk of getting dehydrated because you can’t eat or drink, you need immediate medical attention.
“The issue is not so much having some mild symptoms as there's no treatment anyway,” says Poland. “It is spiralling into a medical situation where supportive care is needed to lessen the severity or save your life.” The most important thing is to not spread the virus, so there are fewer people with severe symptoms at once so the hospitals aren’t overloaded. The government has promised antibody tests which will enable us to see exactly how many people have already had the virus, perhaps without even knowing it. For now the country has to rely on lockdown measures and people self isolating if they experience any of the symptoms.
Maria Mellor is a writer for WIRED. She tweets from @Maria_mellor
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This article was originally published by WIRED UK
