What is long COVID?

What does it mean when we say someone has recovered from COVID-19? Data around recoveries are based on set criteria:

• COVID-19 patients should test negative on two COVID-19 (SARS-CoV-2) RT-PCR tests, done at least 24 hours apart, to be considered COVID-free.
• They should not have a cough or breathing difficulty for 24 hours and fever for 48 hours before being declared fine. 
• They should be discharged from hospitals or given a clean chit by their healthcare provider after testing negative on two consecutive RT-PCR tests.

Despite meeting these criteria, many "recovered" patients say they don't feel well enough to return to normal life (or work) after being discharged. Though their viral load is negative, full recovery, in the case of COVID-19, can be a long-drawn-out process for many people. (Read more: Home-based care for patients who have recovered from COVID-19) 

Being discharged from hospital or testing negative for the SARS-CoV-2 virus (the pathogen that causes the COVID-19 infection), tells you whether you're still contagious but not whether you are feeling perfectly fine now.

Long COVID cases

Cases of post-COVID illness have been reported in various media and peer-reviewed journals. Here's a sampling:

• In August 2020, the scientific journal Nature carried an article by a healthcare professional and "recovered" COVID-19 patient. The writer reported having symptoms such as cough, fever, diarrhoea, pain in the chest and leg pain since March. Her article went on to say that while there is an abundance of data regarding the people who are at risk of developing severe symptoms of COVID-19, the lasting effects of the disease on people has not been taken into consideration.
• Doctors in the UK also took to the journal BMJ to recount the examples they came across, saying "concerns have been raised about the lack of awareness among NHS (National Health Service of the UK) doctors, nurses, paramedics and other healthcare professionals with regard to the prolonged, varied and weird symptoms".
• Healthcare professionals such as doctors have themselves reported having symptoms for as long as four months that have come and gone. These included gastrointestinal symptoms of COVID-19, dehydration and fatigue.
• A professor at the Liverpool School of Tropical Medicine also wrote in BMJ about his experience with COVID-19 with symptoms lasting for nearly seven weeks. The professor's symptoms included exhaustion, loss of sense of smell (anosmia), tightness in the chest and confusion. But he also writes about experiencing different symptoms that have appeared throughout the illness.
• Social media is also replete with people speaking about their experiences of having contracted the disease and living with it for weeks, sometimes months. These recurring symptoms are common among people who contracted the infection but were never admitted to a hospital for treatment.

A report compiled by BMJ after collecting several different instances of long COVID defines the term as "illness in people who have either recovered from COVID-19 but still report lasting effects of the infection, or have had the usual symptoms for far longer than would be expected".

More and more examples of people living with long COVID have also alerted healthcare practitioners of the need to define recovery in the context of COVID-19 and develop a care protocol for these "recovered" patients.

One of the reasons the condition of long COVID hasn't been as well investigated as the respiratory disease itself is due to the lack of empirical evidence supporting it. However, a report published in the journal JAMA studying COVID-19 patients in Italy—one of the first countries to be severely hit by the coronavirus infection—60 days after the onset of the first signs of the disease, found that a high number of people reported symptoms of fatigue, dyspnea or shortness of breath, joint pain and chest pain.

The report found that about 87% of the 179 people who were part of the study reported at least one symptom of COVID-19—mostly fatigue and dyspnea—even two months after they had recovered from the disease.

A study by Italian doctors which was published in Anaesthesia and Analgesia found that patients of this respiratory infection could develop chronic pain, whether they were mildly ill, moderately ill or they developed COVID-19-linked ARDS (acute respiratory distress syndrome is a life-threatening complication of COVID-19).

Another study published in Alzheimer's Research and Therapy focused on the neurological symptoms seen in COVID-19 patients, and reported that those who have recovered from such symptoms or even underlying neurological conditions have a higher likelihood of developing neurological diseases such as Alzheimer's disease.

According to the COVID-19 symptom app in the UK that has the information about 40 lakh people living in the country, about one in 10 people have been sick with the infection for longer than three weeks, even though official medical guidelines around the world suggest that people tend to recover within two weeks.

The NHS of the UK is preparing a portal where people who have been experiencing long-term effects of COVID-19 can discuss symptoms and seek advice from a healthcare professional. A study looking into the long-term effects of the infection on patients is recruiting about 10,000 patients across England—the study will last over one year.

In India, too, examples of long COVID have been reported around the country, and the Health Ministry last month announced an exercise to find out long-term health problems being seen in recovered patients of COVID-19. Medical colleges and hospitals around the country are going to be part of this large-scale exercise to document the health of patients who have been discharged after receiving treatment for the infection.

In recent months, the number of cases in India has skyrocketed to make it the third worst-hit country by COVID-19, only behind the United States and Brazil.