Prolonged COVID is a condition in which people experience COVID-19 symptoms for longer than usual after initially contracting the SARS-CoV-2 virus.
Other terms for long COVID include post-COVID, post-acute COVID, long-tail COVID and long-distance COVID. People with long COVID may refer to themselves as long transportation.
The World Health Organization (WHO) explains that some people may experience long-term effects of COVID-19, whether they need hospitalization or not. These long-term effects may include fatigue, breathing symptoms and neurological symptoms.
In this article, symptoms, possible causes, diagnosis and options for the management and repair of long COVID are discussed.
Long COVID refers to when people still experience symptoms of COVID-19 and do not fully recover for a few weeks or months after the onset of their symptoms.
Some research suggests that people with mild cases of COVID-19 usually recover within 1-2 weeks of contracting the initial SARS-CoV-2 infection. In severe cases of COVID-19 recovery can take 6 weeks or longer.
Currently, researchers can define post-acute COVID-19 as symptoms that last longer than 3 weeks since onset, and chronic COVID-19 as symptoms that last longer than 12 weeks since onset.
Other researchers refer to long COVID as COVID-19 symptoms lasting longer than 2 months.
A 2020 survey by the Centers for Disease Control and Prevention (CDC) indicates that it can take weeks before COVID-19 symptoms disappear and that people need to return to their normal state of health. This also applies to young adults without chronic medical conditions.
In contrast, more than 90% of people discharged from the hospital with the flu recover within two weeks.
Evidence shows that many people may experience symptoms associated with COVID-19 long after their initial infection with the SARS-CoV-2 virus.
Although it is still unclear how many people have experienced COVID for a long time, the data from the COVID symptom study app indicate that 1 in 10 people with the disease experience symptoms for 3 weeks or longer.
Data from the Office for National Statistics of the United Kingdom found similar results, with about 1 in 10 respondents testing positive for COVID-19 showing symptoms lasting a period of 12 weeks or longer.
This means that there could be more than 5 million cases of long COVID around the world.
One 2021 study found that more than three-quarters of COVID-19 patients in a hospital in Wuhan, China, still had at least one symptom six months after discharge from the hospital.
This is in line with a 2020 study from Italy which found that 87.4% of COVID-19 patients experience at least one symptom two months after discharge from the hospital.
A Swiss study from 2020 also notes that as many as 1 in 3 people with a mild case of COVID-19 still experienced symptoms after 6 weeks.
Using a statistical model, a preprint 2020 study found that COVID is more likely to occur in older adults, people with a higher body mass index (BMI), and women.
It is also noted that individuals who experience more than five symptoms during the first week of illness are more likely to develop long-term COVID.
Some evidence also suggests that many people with long COVID are health workers.
The CDC notes a variety of symptoms for COVID-19. They also note that the symptoms that people usually report in long COVID are:
- fatigue
- short of breath
- Cough
- joint pain
- chest pain
People can also experience:
- brain fog, in which they find it harder to think and focus clearly
- depression
- muscle aches
- headache
- fever, what can come and go
- palpitations, or a feeling of the heart beating
People can also develop long-term complications that affect the organs. These complications are less common, but may include:
- inflammation of the heart muscle
- abnormal lung function
- severe kidney injury
- a result
- hair loss
- problems with smell and taste
- sleep problems
- problems with memory and concentration
- anxiety
- mood changes
Researchers are not sure what causes long recovery times of COVID-19, but some causes of long COVID may include:
- a reduced or lack of response of the immune system
- relapse or re-infection of the virus
- inflammation or a reaction of the immune system
- a change in physical functions due to bed rest or inactivity
- post-traumatic stress
COVID-19 can cause long-term changes in the immune system, which can affect the organs. These changes, especially in the lungs, can take longer than the body takes to remove the virus.
If someone has long experienced COVID, they may have received a COVID-19 diagnosis if they had access to a coronavirus test.
To diagnose long COVID, a physician can take a complete medical history and assess all COVID-19 symptoms, from the onset of infection to current symptoms. The doctor can look at:
- blood pressure
- temperature
- heart rate and rhythm
- lung and respiratory function
Although there is no specific test to diagnose long COVID, doctors can perform tests to rule out any other possible causes of the symptoms. Tests can vary depending on what symptoms a person has, but may include blood tests to check:
- whole blood count
- electrolyte
- kidney function
- liver function
- troponin, to test for heart muscle damage
- inflammation levels
- muscle damage
- D-dimer, to check for blood clots
- heart health
- iron levels
Other tests may include:
- a chest X-ray
- a urine test
- an electrocardiogram to look at heart problems
Home remedies for managing long COVID are likely to be similar to home treatments for COVID-19. Options include:
- the use of over-the-counter pain relief, such as paracetamol, to relieve painful symptoms or fever
- rest and relax
- set achievable targets to achieve
- gradually increase exercise levels, as appropriate
Taking care of general health is also important. These include:
- to a healthy diet
- get quality sleep
- restriction of alcohol intake
- limit caffeine intake
- do not smoke
People may also find it helpful to connect with a support network, especially if COVID has long been affecting their mental health, financial security or social well-being.
There is currently no clear timeline for long COVID recovery. Research reports that people may experience symptoms 60-90 days after the initial infection, and that some people may experience symptoms longer than that.
Other viruses, besides SARS-CoV-2, can also cause prolonged symptoms. According to the British Heart Foundation, the symptom duration of other viruses indicates that long COVID symptoms can disappear within 3 months. People can continue to feel tired for up to six months.
However, these are rough estimates, and recovery times may differ for each individual.
Because of how new the condition of long COVID is, researchers and health professionals are still trying to understand the causes, treatment options, and possible recovery times.
People who experience long COVID can call a doctor for advice.
However, a person needs medical help if they experience the following:
- aggravating shortness of breath
- unexplained chest pain
- a new state of confusion
- weakness
- changes in sight, hearing or speech
If someone needs immediate medical attention, someone can call 911 and inform them that they have COVID-19-related symptoms.
As more people discuss their experience of long COVID, some countries are starting to offer more formal support. In the UK, for example, a COVID Recovery resource from the National Health Service (NHS) is now available.
In the United States, however, informal support groups – such as Body Politic – are still the main resource for people experiencing long-term COVID symptoms.
Some people with COVID-19 symptoms may recover within a few weeks. However, it can take much longer for others to recover.
Long COVID is the term for COVID-19 symptoms that persist weeks or months after the initial infection.
People can discuss a treatment plan with a doctor. Taking steps to look after their health and well-being, such as following a healthy diet, getting plenty of rest and doing gentle exercise, can help someone manage long COVID.
Medical treatment may be needed to treat secondary infections or complications.