Long COVID is often associated with persistent fatigue and brain fog following a bout of coronavirus.
A new study has found however that the set of symptoms associated with the illness is wider than first thought.
It found long COVID sufferers have, among other symptoms, been suffering from hair loss and loss of libido, as well as erectile dysfunction in men.
Using the anonymised health records of around 2.4 million people in the UK, researchers found patients who had a record of COVID-19 infection reported some 62 symptoms more frequently 12 weeks after the initial infection than those without a record of infection.
The research, conducted by researchers from the University of Birmingham, alongside clinicians and researchers across England, studied 486,149 people with prior infection, against 1.9 million people with no indication of having had coronavirus.
The study, published in the journal Nature Medicine, also uncovered demographic groups that are at greater risk of developing long COVID.
Long COVID symptoms 'extremely broad'
The persistent symptoms spotted by the researchers are split into three categories: respiratory symptoms, mental health and cognitive, and then a broader range of symptoms.
The most common are the loss of the sense of smell, shortness of breath, chest pain, and fever.
But some of the common symptoms have thus far not been widely associated with long COVID, including erectile dysfunction, loss of libido, hair loss, and sneezing.
Other surprising findings include amnesia, apraxia (the inability to perform familiar movements or actions), loss of bowel control, hallucinations, and swelling of the limbs.
"This research validates what patients have been telling clinicians and policymakers throughout the pandemic, that the symptoms of Long Covid are extremely broad and cannot be fully accounted for by other factors such as lifestyle risk factors or chronic health conditions," said Dr Shamil Haroon, Associate Clinical Professor in Public Health at the University of Birmingham, the senior author on the study.
"The symptoms we identified should help clinicians and clinical guideline developers to improve the assessment of patients with long-term effects from COVID-19, and to subsequently consider how this symptom burden can be best managed," he added.
Who is most at risk?
The study also analysed demographic data to see who may be most at risk of developing long COVID.
It suggests that females and younger people are more at risk, but also those belonging to a black, mixed, or another ethnic group.
Furthermore, people from lower socioeconomic backgrounds, smokers, people who are overweight or obese, and those with other health conditions, were more associated with having long COVID.
"Our data analyses of risk factors are of particular interest because it helps us to consider what could potentially be causing or contributing to long COVID," Anuradhaa Subramanian, a research fellow at the University of Birmingham and a lead author of the paper, said.
"We already know that certain modifiable traits such as smoking and obesity put people at increased risk of various diseases and conditions, including long COVID. However, others such as biological sex and ethnicity also appear to be important.
"Women are for example more likely to experience autoimmune diseases. Seeing the increased likelihood of women having long COVID in our study increases our interest in investigating whether autoimmunity or other causes may explain the increased risk in women.
"These observations will help to further narrow the focus on factors to investigate that may be causing these persistent symptoms after an infection, and how we can help patients who are experiencing them".
Long COVID has been described as a “pandemic within the pandemic,” with studies suggesting as many as 40 per cent of those infected with COVID-19 could develop persistent symptoms long after the initial illness.
According to the Centers for Disease Control and Prevention (CDC) in the US, nearly one in five US adults who have had COVID-19 still have long COVID.