About 5-10% of people with COVID infection experience long-term COVID, with symptoms lasting three months or longer.
Researchers have proposed several biological mechanisms to explain long-lasting Covid. However, in a Perspective article published in the latest Medical Journal of Australia, we argue that much, if not all, of long-term COVID is driven by the virus present in the body.
Since relatively early in the pandemic, there has been recognition that in some people, SARS-CoV-2 – or at least remnants of the virus – can persist for long periods of time in various tissues and organs. This principle is known as “viral persistence”.
Although the long-term presence of residual viral fragments in the bodies of some people is now well established, what is less certain is whether live virus, not just old fragments of virus, persist over long periods of time – and If so, is this what causes long-term COVID? This distinction is important because live viruses can be targeted by specific antiviral methods in a way that “dead” viral fragments cannot.
Going viral has two important implications:
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When it occurs in some highly immunocompromised people, it is thought to be the source of new and largely distinct variants, such as JN.1.
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It has the potential to cause symptoms in many people in the wider population, even after serious illness. In other words, a long-lasting infection may be caused by a long-lasting infection.
What does the research say?
While there are no studies that confirm that persistent virus causes long-term COVID, several recent major papers collectively make a compelling case.
In February, a study in Nature found that a large number of people with mild COVID symptoms had an increased amount of time for the virus’s genetic material, so-called viral RNA, to be shed from the respiratory tract. People with persistent leakage of this viral RNA – which almost certainly represents the presence of live virus – were at greater risk of long-term COVID.
Other key documents found viral RNA and proteins replicating in the blood fluids of patients years after initial infection, a sign that the virus is replicating for long periods of time in some hidden reservoir in the body, perhaps blood cells. Including.
Another study detected viral RNA in ten different tissue sites and blood samples 1–4 months after acute infection. This study found that people with persistently positive viral RNA had a higher risk of long-term COVID (measured four months after infection).
The same study also revealed where the virus resides in the body. The gastrointestinal tract is a site of considerable interest as a long-term viral locus.
Earlier this week, evidence that persistent viruses increase the likelihood of long-term COVID has been published as part of the RECOVER initiative, a collaborative research project aimed at reducing the risk of long-term COVID. to address the effects of.
However, formal evidence that a virus capable of replicating can persist in the body for years remains elusive. This is because it is technically challenging to isolate live virus from the virus where it “hides” inside the body.
In its absence, we and other scientists argue that the cumulative evidence is now compelling enough to motivate action.
What should happen next?
The obvious response is to fast-track trials of known antivirals to prevent and treat long-term COVID.
This should include more left-field therapies, such as the diabetes drug metformin. This has the potential to have dual benefits in the context of prolonged Covid:
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Its antiviral properties, which have shown surprising efficacy against long-term Covid
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As a potential therapeutic in the treatment of fatigue-related impairments.
However, another major thrust should be the development of new drugs and establishment of clinical trial platforms for rapid testing.
Science has revealed exciting therapeutic options. But translating these into usable forms in the clinic is a major hurdle that requires support and investment from governments.
Revelation and prevention of long-lived COVID
The notion of “long infection” as a contributor or even driver of long Covid is a powerful message. This can help to highlight the condition in the eyes of the wider community and raise awareness among the general public as well as medical professionals.
This should help raise awareness in the community about the importance of reducing re-infection rates. It’s not just your first infection, but each subsequent COVID infection that carries the risk of long-term COVID.
Long COVID is common and is not limited to people at high risk of severe acute illness, but affects all age groups. In one study, the greatest impact was on those aged 30 to 49.
So, for now, we all need to reduce our exposure to the virus with the tools available, a combination of the following:
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Clean indoor air approach. In its simplest form, this means being mindful of the importance of well-ventilated indoor spaces, opening windows and improving airflow as COVID spreads through the air. More sophisticated methods of ensuring indoor air is safe include monitoring quality and filtering air in areas that cannot be easily ventilated naturally.
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Using high-quality masks (ones that fit well and don’t let air in easily, such as N95-type masks) in settings where you are not confident in the quality of indoor air and/or where there is crowding
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Testing, so you know when you are positive. Then, if you are eligible, you can receive treatment. And you can be vigilant about protecting people around you with masks, staying at home where possible, and ventilating spaces
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Staying updated with COVID booster doses. Vaccines reduce long-term Covid and other post-Covid complications.
Hopefully one day there will be better treatment and a cure for long term Covid. But in the meantime, growing awareness of the biomedical basis of long-lasting COVID should prompt physicians to take patients more seriously as they try to access treatments and services that already exist. .
,Author: Brendan Crabb, Director and CEO, Burnet Institute, Gabriella Khoury, Theme Leader, Antiviral Immunity, Burnet Institute, Michelle Schaller, Senior Research Fellow, Burnet Institute)
,disclosure statement: Brendan Crabb and the Institute he leads receive research grant funding from the National Health and Medical Research Council of Australia, the Medical Research Future Fund, DFAT’s Center for Health Security and other Australian federal and Victorian state government bodies. He is President of The Australian Global Health Alliance and Pacific Friends of Global Health in an honorary capacity. And he serves on the boards of the Kids Research Institute Australia, MRNA Victoria, the advisory committees of the Sanger Institute (UK), the Brain Cancer Center (Australia), and is a member of OzSAGE and The John Snow Project, all with honorary positions. ,
Gabriela Khoury receives funding from the Medical Research Future Fund.
The Mitchell Scholar receives funding from the Medical Research Future Fund. She is affiliated with Clinic Nineteen, a clinic that specializes in long COVID.)
This article is republished from The Conversation under a Creative Commons license. Read the original article.
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