Because COVID-19 is a new disease, scientists are unsure about the effects months or years after the initial illness. Researchers have theorized that the virus responsible for COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), may cause similar effects to other coronaviruses, such as those that cause severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). Long COVID refers to a condition where people continue to experience COVID symptoms long after they have recovered and tested negative. People suffering with long COVID are called long haulers who, due to COVID-19, either experience some permanent damage to their lungs, heart, kidneys, or brain or continue to experience lingering symptoms despite no detectable damage to these organs. Other terms for long COVID include post-COVID, post-acute COVID, long-tail COVID, and long-haul COVID. People with long COVID may refer to themselves as long haulers. The World Health Organisation (WHO) explains that some people may experience long-term effects of COVID-19, whether they required hospitalization or not. These long-term effects may include fatigue, respiratory symptoms, and neurological symptoms. Although it is still unclear how many people have experienced long COVID, data from the COVID Symptom Study app suggest that 1 in 10 people with the illness experience symptoms for 3 weeks or longer.
According to Dr. John Brooks, chief medical officer for the CDC’s Covid-19 response, long COVID is still ‘not well understood’ by health experts. He believes that the primary care physician can identify whether a person is suffering from long COVID symptoms or if it’s just some other illness. “If you’re having symptoms you haven’t had before, something new following Covid (such as) chest pain, difficulty breathing, you can’t get your thinking clearly, you’re just not getting better the way you thought you should, have a low threshold to seek care,” Brooks told a House committee.
Researchers analysed data on people who reported their symptoms of long Covid on the COVID Symptom Study app and identified two main groups of symptoms. One is mainly respiratory, such as a cough and feeling breathless, but also includes fatigue and headaches. The second group of symptoms affects many parts of the body, including the heart, brain and the gut. In the study of 4,182 people, heart symptoms were commonly reported, such as palpitations or increased heartbeat, as well as pins and needles, numbness and ‘brain fog’. Researchers have analysed data from the COVID Symptom Study app to discover who is most at risk of developing long Covid. They found that older people, women, and those who had five or more symptoms in the first week of becoming ill with Covid-19 were more likely to develop long Covid.
They found that long Covid affects around ten per cent of 18-49 year olds who get Covid-19, increasing to 22 per cent of people over 70. The researchers also found people with asthma were also more likely to develop long Covid. This was the only clear link they found to existing health conditions in people who developed long Covid.
Researchers in Leicester followed up more than 1,000 people who had been admitted to hospital with Covid-19. In this study, the people who were most likely to be affected by long Covid tended to be White women aged 40 to 60 with two or more medical conditions such as a cardiovascular condition, asthma or type 2diabetes. This is different from those who are most likely to need hospital treatment for Covid-19, who are more likely to be male and from an ethnic minority background.
Long Covid is not contagious though. Long Covid symptoms are caused by one’s body’s response to the virus continuing beyond the initial illness.
To avoid passing coronavirus on to others, one should self-isolate for 10 days from their original symptoms or positive test, or if after 10 days one still has temperature, or runny nose or sneezing, or sickness or diarrhoea, until these symptoms have gone.
Researchers are not certain what cause the prolonged effects of COVID-19, but some possible causes of long COVID may include:
- a reduced or lack of response from the immune system
- relapse or reinfection of the virus
- inflammation or a reaction from the immune system
- deconditioning, which is a change in physical function due to bed rest or inactivity
- post-traumatic stress
Some people with COVID-19 symptoms may recover in a few weeks. However, recovery may take much longer for others. Long COVID is the term for COVID-19 symptoms that continue for weeks or months after the initial infection. Hence, it is important to undergo a full body checkup after one has recovered from COVID to avoid long term health hazards.
