Nov 29, 2024 13:00:00

'Long COVID,' a condition where symptoms of the new coronavirus last for a long time, may be caused by persistent infection

About 5-10% of people infected with the new coronavirus disease (COVID-19) experience 'long COVID,' a condition in which symptoms last for more than three months. It has been revealed that long COVID

may be caused by mitochondrial dysfunction and abnormal activation of T cells in tissues throughout the body , but it has now been discovered that it is caused by a virus that remains in the body.

Towards a cure for long COVID: the strengthening case for persistently replicating SARS‐CoV‐2 as a driver of post‐acute sequelae of COVID‐19 | The Medical Journal of Australia
https://www.mja.com.au/journal/2024/221/11/towards-cure-long-covid-strengthening-case-persistently-replicating-sars-cov-2

Long COVID appears to be driven by 'long infection'. Here's what the science says
https://theconversation.com/long-covid-appears-to-be-driven-by-long-infection-heres-what-the-science-says-244635

From a relatively early stage in the COVID-19 pandemic, it became clear that in some people, the novel coronavirus (SARS-CoV-2), or at least remnants of SARS-CoV-2, can persist in various tissues and organs for extended periods of time, a phenomenon known as 'persistent infection.'

It has already been well established that some people retain remnants of the virus in their bodies for long periods of time, but the mystery of whether not only remnants of the virus (inactivated virus) but also live virus (activated virus) remain in the body and, if so, whether this is the cause of long COVID has remained unclear until now.

A virology research team at the Burnet Institute in Australia points out that if the mystery of persistent infection can be unraveled, two things may become clear:

1: Persistent infection in severely immunocompromised patients is thought to lead to the emergence of variants with very different appearances, such as JN.1 .
2: It may continue to cause symptoms in many people in the wider population once the acute illness has passed -- in other words, prolonged infection could lead to Long COVID.

'While there is no single study to date that shows that persistent infection is the cause of long COVID, the latest papers taken together make a compelling case,' the Burnett Institute research team argues.

A paper published in Nature in February 2024 revealed that many patients with mild COVID-19 were shedding viral RNA, the genetic material of the virus, from their respiratory tract for a long period of time. Patients who continued to shedding viral RNA were almost certain to have active viruses remaining in their bodies, and were at high risk of developing long-term COVID-19.

Additionally, another paper reported that replicating viral RNA and proteins were detected in the blood of patients years after their initial COVID-19 infection, suggesting that the virus likely continues to replicate in the body for long periods of time, possibly within blood cells.

Another study found that viral RNA was detected in 10 different tissue sites and blood samples 1 to 4 months after acute infection. Furthermore, it was found that people who persistently tested positive for viral RNA were at higher risk for long COVID. This study also provides clues about where the virus persists in the body, with the gastrointestinal tract being one of the most interesting sites for the virus to remain dormant for a long period of time.

Moreover, further evidence that persistent infection increases the likelihood of long COVID was published in November 2024 as part of RECOVER , a collaborative research project aimed at addressing the effects of long COVID. There is still no evidence that replication-competent virus can survive in the body for years, but this is due to 'technical challenges in isolating active virus from reservoirs in the body where it hides.'

Based on these research papers, the Burnett Institute research team writes, 'We argue that the theory that persistent infection contributes to long COVID is compelling, even if active virus does not persist in the body.'

As a response to this, the research team recommends rapidly testing known antiviral drugs for the prevention and treatment of long COVID, including the diabetes drug metformin. In fact, it has been reported that antiviral drugs have shown surprising efficacy against long COVID , and they are also expected to be a potential treatment for fatigue-related disorders.

Another big driver will be the development of new drugs and the establishment of a clinical trial platform for rapid testing, the team argues, but translating this into a form that can be used in the clinic will be very difficult and will 'require government support and investment,' the team said.

The theory that persistent infection is a contributing factor or promoter of long COVID could help to unravel the mystery of long COVID and raise awareness among medical professionals. In addition, the research team argues that it could help raise awareness in the community about the importance of reducing the reinfection rate of COVID-19. In fact, it has been shown that the risk of developing long COVID increases with the number of SARS-CoV-2 infections.

The more times you are infected with the new coronavirus, the higher your risk of long COVID - GIGAZINE