Why virus effects could last years

Patients recovering from Covid-19 will experience chronic problems long after they are healed.

These include damage to the heart, lungs, kidneys, and brain. Other problems include fatigue, a racing heartbeat, laboured breathing, difficulty in concentrating, aching joints and the inability to smell.

The data that informed these conclusions came from hospitals in Italy, UK and the US but infectious diseases experts from the Aga Khan University Hospital told the Nation that “there is no reason to believe it will be different in Kenya”.

Prof Rodney Adam, who has been looking after severely sick Covid-19 patients at the Aga Khan Hospital, told the Nation that once healed, many patients complain of low exercise tolerance due to the damage meted on the lungs by the virus.

He said the patients also stay longer in the hospital before the oxygen levels in their bodies rise to a tolerable level.

“That is always an indication of how well their lungs are doing, but they may not be back to normal for months,” he said.

Respiratory issues

Pulmonologist Dr Jeremiah Chakaya explained that any respiratory infection (Covid-19, pneumonia and tuberculosis) scars the lungs. The parts that are damaged die and never function again.

A lung that cannot use all of itself has reduced capacity to do its work of letting oxygen in and carbon dioxide out.

This was expected in Covid-19. A study published in the journal Nature reported that Covid-19’s sister virus, Sars, which killed 700 in 2003, left patients with lesions in their lungs 15 years later.

It would be hard to put a finger on all the effects of Covid-19 because there are no studies yet that are trailing survivors but doctors are conflicted on whether the severe consequences that accompany patients after recovery are due to secondary issues, such as underlying chronic diseases.

Prof Rodney said he was shocked at just how many of the patients that were wheeled into the Aga Khan University Hospital were diabetic and did not even know it.

“Many patients had diabetes and obesity, and Covid-19 may have unmasked those,” Prof Rodney said.

This is a plausible explanation given the manner in which Covid-19 attacks the body.

Battlefield

Thumbi Ndung’u, a professor of virology based in South Africa, said the virus that causes Covid-19 (Sars -CoV-2) uses a spike protein on its body to get access into the body by attaching itself on to the Angiotensin-converting enzyme 2 (ACE2).

This enzyme is on major organs in the body — the lungs, heart, gut, kidneys, blood vessels, and nervous system — which are then placed on Covid-19’s sniper scope during infection.

When the body is under this much stress, it defends itself, sometimes irrationally, to the point it kills or leaves the patient with permanent damage to the brain or the heart. This is called a cytokine storm.

Cytokines are small proteins released by cells in the body when the body defends itself against a disease. When the Covid-19 virus goes to the lungs, the body recognises it as an enemy that needs to be eliminated, and the body summons these cells to where the virus is to attack it.

Being a battlefield, this war causes an inflammation on the body. For obese people, this process is excessive, leading to high levels of cytokines released. This causes hyperinflammation.

Dr Anthony Etyang’, a consultant physician and clinical epidemiologist based in Kilifi, said: “This harms the patient through organ failures and can result in death.”

The heart suffers the most in this process. ACE2 receptors serve more than just “receiving” the Covid-19 virus.

It also shields the heart from attacks as well as breakdown the hormone angiotensin II which increases blood pressure. Covid-19 makes the edges of these receptors blunt and therefore reducing their effectiveness.

Studies

A paper published in June by researchers from the University of Miami in the journal Heart Rhythm had shocking revelations: the blood enzyme troponin, which is often very high when someone is having a heart attack, was high in a quarter of the patients who had been discharged from hospital after healing from Covid-19.

This was for people who are diabetic or hypertensive, but another paper published two weeks ago in the journal JAMA Cardiology found that when the heart pictures were taken of people who had tested positive for Covid-19 in a US hospital, 78 per cent of them had inflamed heart muscles and they had not history of other sicknesses.

Given the sly nature of viruses, Omu Anzala knows only survivor studies that follow patients will shed light into how much damage Kenyans will endure.

The professor of viruses from the University of Nairobi will work with researchers from Kenyatta National Hospital, Mbagathi and Coast General Hospital to follow up about 300 Covid-19 patients for a year after they are discharged from hospital.

The study began in March this year.

“It will involve thorough medical checkups of the patients through blood tests, X-rays, echocardiograms (heart images), and physical examinations,” Prof Anzala said.

Prof Anzala’s seeks to answer questions that he has seen in other viruses. For instance, the nine types of Herpesviruses, he says infect people and then stay latent in the body and then years later, trigger other infections such as severe meningitis.

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