Most people who develop coronavirus disease 19 (COVID-19) recover within 2–6 weeks, but some experience lasting symptoms. Others with severe COVID-19 may develop complications, require rehabilitation after a hospital stay, or both.
Because COVID-19 is a new disease, scientists are unsure about the effect’s 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).
According to a 2020 study, around 30% of people who recovered from severe SARS or MERS had long-term lung abnormalities. A 2009 study found that 40% of people who survived SARS still experienced chronic fatigue about 3.5 years later, on average.
But while SARS, MERS, and COVID-19 are caused by viruses from the same family, there are key differences among them, as the 2020 study highlights. For this reason, looking to the other two diseases does not provide a reliable way to predict COVID-19’s long-term effects.
Research into the impact of COVID-19 is ongoing. Initiatives such as the COVID symptom study are tracking peoples’ symptoms and the long-term consequences of the disease via a mobile app.
Most people who develop COVID-19 experience a mild or moderate illness that improves on its own. However, some people who have had a mild or moderate illness go on to develop lasting symptoms that can be severe — even after they have recovered from the initial infection.
When these symptoms are prolonged, people sometimes refer to the issue as “long COVID” or to the people who have it as “long-haulers.”
People with mild or moderate COVID-19 often go on to report:
- extreme fatigue
- muscle weakness
- a low-grade fever
- trouble concentrating
- lapses in memory
- mood changes
- trouble sleeping
- a sensation of pins and needles
- a loss of taste and smell
- a sore throat
- difficulties swallowing
- skin rashes
- shortness of breath
- chest pain
- heart palpitations
- the new onset of diabetes or high blood pressure
These symptoms may last for weeks or months after the body has cleared the virus.
It seems that anyone, including young people and those with no pre-existing health conditions, can develop long COVID. Citing a telephone survey, the World Health Organization (WHO) observe that 20% of people aged 18–34 reported prolonged symptoms.
Around 10-15% of people who develop COVID-19 experience severe symptoms, and approximately 5% become critically ill. People with severe symptoms can also experience long COVID.
In addition, people with a more severe form of the illness may be more likely to experience complications. As the WHO note, the complications can involve damage to:
- The lungs: An August 2020 study found that people with severe COVID-19 are often discharged with signs of pulmonary fibrosis, a type of lung damage. In some people, it can cause long-term breathing difficulties.
- The heart: According to a June 2020 review, 20-30% of people hospitalized with COVID-19 have signs that the illness has affected their heart muscle. The researchers speculate that in some people, COVID-19 may also cause myocarditis, inflammation of this muscle.
- The nervous system: An April 2020 study with 214 participants found that people with severe COVID-19 were more likely to experience neurological manifestations, such as dizziness, nerve pain, and impaired consciousness.
Currently, doctors are not sure how these complications will affect people in the long term.
People who spend time in the hospital and require mechanical ventilation may also experience other difficulties. A July 2020 study lists the following complications of ventilator treatment:
- chipped teeth
- lacerated lips, tongue, or throat
- injured vocal cords
- collapsed lung
- heart rhythm problems
People who leave the hospital after having COVID-19 need ongoing support and rehabilitation to help them recover.
During the COVID-19 pandemic, many people have found it difficult to access treatment for their ongoing symptoms.
Below are just a few of the factors that have prevented people from accessing necessary medical care:
- Lack of awareness: Early in the pandemic, doctors were not aware that COVID-19 could cause lasting symptoms. Early guidance indicated that for most people, the illness would be short-term.
- Lack of information: Scientists are not yet sure what causes long COVID or how best to manage it. This can mean that even when doctors are aware of the potential long-term impact, they may not know how to provide treatment.
- False-negative test results: According to an article in BMJ, false negatives are common among people with COVID-19. This, coupled with a lack of access to testing in some areas, means that many people with long COVID do not receive medical attention. For this reason, the article’s authors recommend that doctors do not require positive test results in order to diagnose chronic COVID-19 symptoms.
A recent study on post-COVID manifestation of symptoms showed that only 10.8 percent of survivors assessed in the study had no symptoms or manifestations post COVID. About 72 percent of participants had major complaints of fatigue (similar to post-SARS fatigue) and the rest, a small percentage had critical manifestations such as lung fibrosis, kidney failure, myocarditis and stroke.
This only makes it imperative for us to be more aware of the scope of multi-organ impact that the virus can have after it has left the body. The presence of post-COVID symptoms and complications can significantly increase the time spent in a hospital/away from work. Here are six organs and organ systems that can be affected due to COVID-19, leading to lingering symptoms and signs after recovery, also dubbed as “Post COVID syndrome”:
Post-COVID respiratory system:
A few patients who recover from covid-19 tend to complain of persistent fatigue, shortness of breath and the need to take deep breaths, hindering their abilities to complete even little routine tasks. This could possibly be due to the long-standing damage to the air sacs and lung tissue. The scars formed in the lung as a result of the inflammatory changes during the disease can lead to long-term breathing problems.
Post-COVID heart and blood vessels:
“It would be fair to say that the post-COVID effects on the heart and the circulatory system can be life-threatening and difficult to treat, especially in patients with pre-existing heart diseases. Doctors have observed that even after having tested negative for COVID-19, patients have had chronic fatigue, abnormal heart rate, palpitations, chest pain and lasting heart muscle damage (as seen on imaging studies). This contributes to a rise in the risk of developing heart failure and other complications like cardiomyopathy,” she said.
The other important observation made in patients with COVID-19 is the formation of blood clots- while large clots can directly contribute to heart attacks and strokes, the smaller clots can travel to end organs like the liver, kidney, etc and cause significant organ damage.
Another rising problem is the low kidney function that is observed in hospitalised patients and even in those who have been discharged. The presence of high blood pressure and diabetes further enhances the risk of developing kidney dysfunction post-COVID.
Patients have had low urine output, infrequent urination, and sometimes, the damage has been extensive enough to require dialysis. The kidney damage, which is being observed even in younger patients or those with no history of kidney disease, is largely attributed to direct attack by the virus, low blood oxygen levels, cytokine storm and blood clots that might clog the kidneys.
Liver injury is a consequence of viral replication and damage to the hepatic tissue during the infection. Patients admitted for moderate to severe COVID-19 have been noted to have elevated levels of liver enzymes and abnormal liver function. A retrospective study in China noted that over one-third of patients hospitalised for COVID-19 had abnormal liver function, and a higher proportion was observed in males.
It has been observed that in some patients, the liver function test does not return to normal levels even post recovery, and this too can be attributed to cytokine storm, pneumonia-associated low oxygen levels, and side effects of drugs used to treat the infection.
Some patients who have had COVID-19 have developed strokes, seizures, and mild to severe inflammation in the brain, leading to long term impacts. Some patients who recover with mild symptoms have reported feeling confused, having foggy thoughts, dizziness, blurred vision, inability to focus, etc.
Researchers believe that COVID-19 may even cause temporary paralysis (Guillain-Barre syndrome) and increase risks of developing Parkinson’s and Alzheimer’s disease in some patients.
Post-COVID digestive system:
Covid-19 can potentially disrupt nutrient absorption by the gastrointestinal system, making it more difficult for the body to absorb essential nutrients and electrolytes.
Many patients often complain of nausea, abdominal discomfort, loss of appetite, persistent diarrhoea and symptoms of gastritis after recovering from COVID, making it difficult to return to a regular, normal diet. Although this is mostly temporary, complications like gastrointestinal bleeding have been observed in some patients.