Long-term effects of Covid-19: ‘You don’t want to get this virus if you don’t have to’

It can be tempting to think that Covid-19 patients fall into one of two categories.

Category 1: Young, otherwise healthy individuals who experience mild symptoms and recover at home.

Category 2: Older people and people with pre-existing health problems who become seriously ill and go to the hospital.

While it is true that there is a spectrum of risk when it comes to the severity of the disease, it is becoming increasingly clear that not everyone fits perfectly into one of these categories.

For many people, the labels “mild” or “severe”, “sick” or “recovered” are blurred by their experience of ongoing, sometimes debilitating symptoms, weeks or months after the first infection.

Both anecdotal reports and a growing body of research suggest that persistent fatigue, shortness of breath, “brain fog,” and muscle aches, among other symptoms, are affecting people for some time after the infection clears.

So what do we know about the lingering health effects of the coronavirus, and how concerned should we be?

Health effects can last for months

It’s hard to say what proportion of people with Covid-19 face medium and long-term health impacts given how new the virus still is, said Dr. Kirsty Short, a virologist at the University of Queensland.

“It’s definitely happening, I just don’t think we know how common it is,” Short said.

In July, researchers in Italy found that nearly 90 percent of patients with acute infections still had symptoms two months later.

Research from the US and UK, which follows a much broader group of people affected by Covid-19, suggests that symptoms persist in around 10 to 15 percent of cases.

In the same way that the virus can sometimes cause serious illness in young, otherwise healthy people, persistent symptoms seem to affect people of all ages, including those without underlying health problems.

The long-lasting effects are also not limited to those who are seriously ill when first infected.

People with no symptoms or with a mild case of Covid-19 can also face a prolonged illness. Sometimes these symptoms take weeks or months to appear.

The virus affects multiple organs.

SARS-CoV-2 is primarily considered a respiratory virus, but the damage caused by Covid-19 is not always limited to the lungs.

The virus binds to ACE2 receptors in the body, which are found in large numbers in the respiratory tract, but also in the heart, blood vessels, kidneys, liver, and gastrointestinal tract.

In some cases, the virus itself may be causing damage to the body’s organs.

But researchers suspect that high levels of inflammation in the body, triggered by the immune system trying to rid itself of the virus, are wreaking havoc, even after the infection is gone.

“Most likely they had this overwhelming inflammatory response, which we know occurs in COVID-19 patients, and then it has had side effects.”

Covid-19 can damage multiple organ systems, including:

Light: The lungs can be damaged when the virus enters cells in the airways. It can cause stiff, scarred tissue that makes it difficult for the lungs to do their job of oxygenating the blood, leaving people short of breath.

Heart: The virus can cause inflammation of the heart muscle or heart failure when the organ does not pump blood as well as it should. The heart can also fail from lack of oxygen.

Brain: If the virus enters the brain, it can cause a sudden and serious infection. Neurological symptoms can also be the result of inflammation in the brain or strokes caused by blood clots.

Symptoms seen in other infections

Some patients, who describe themselves as “long carriers” of Covid-19, describe debilitating fatigue, difficulty exercising, and general “mental confusion” months after the infection has cleared.

Short said post-viral fatigue is seen in other viral infections as well.

“We know that the Epstein-Barr virus, which causes glandular fever, has also been linked to chronic fatigue syndrome,” he said.

Similarly, there is evidence to suggest that Covid-19 can cause heart damage, which is not unusual for a virus, said Dr. Linda Gallo of the University of Queensland.

“We know from SARS that there was evidence of cardiovascular involvement,” said Gallo, who is investigating how the coronavirus affects the heart.

“However, it was generally considered to be fairly self-limiting and did not persist beyond the recovery period.

While research on long-term cardiovascular effects is limited, Gallo said some of the preliminary evidence is concerning.

“The fact that there are people who [have] he recovered at home and had fairly mild symptoms, now they are showing evidence of heart damage that is troublesome and surprising. “

Gallo is part of a study investigating the long-term effects of Covid-19, especially in people with diabetes, and is currently looking for people who have had coronavirus to participate in a study.

Although it is too early to say what the impact is on people with existing diabetes, he said there is a possibility that Covid-19 is linked to the onset of diabetes.

“The idea is that the virus directly attacks the pancreas. That is just a hypothesis, there is no direct evidence for that at this time,” he said.

“It could be multifactorial, therefore a combination of direct effects of the virus and a general hyperinflammatory response.”

A timely reminder

Several studies are currently underway to investigate whether Covid-19 leaves a lasting impact on health and, if so, to what extent.

Short said that without long-term studies, it is difficult to know how concerned we should be about Covid-19 in contrast to other existing viral infections.

“The question is: if you took a virus of similar severity and similar duration, would you also see long-term complications?” she said.

“It is very possible that we are seeing this with SARS-COV-2 due to the large number of infected people.”

Still, the appearance of symptoms in the future is a reminder of why it is important to take precautions.

“I think it’s just another reason we’re taking all these steps … because you just don’t want to get this virus if you don’t have to.”

– ABC