As we continue to grapple with the COVID-19 pandemic, a new concern is emerging. A recent study by the National Institutes of Health (NIH) has revealed a startling fact: the risk of Long COVID after reinfection by the Omicron variant of SARS-CoV-2 is nearly 20%. This is almost double the risk after the initial infection, which stands at approximately 10%.
Despite the wide reporting of these findings, it seems to have done little to shift public attitudes or influence policy. This could be due to the prevailing narrative that SARS-CoV-2 is "just another respiratory virus" and that COVID-19 will eventually "become like the flu". This perception gap between the reality of COVID-19 risks and public understanding is alarming.
The NIH study aligns with another recent study that found an increased risk of Long COVID in children upon reinfection. These findings may explain the recent advice from the US government to avoid reinfection due to cumulative risks.
Long COVID has been downplayed by some, citing the extensive list of over 200 possible symptoms as a reason for skepticism. However, there are sound biological reasons for this condition to affect the body in so many different ways. The virus uses the Angiotensin-converting enzyme receptor 2 (ACE2) to infect human cells. This receptor is found almost everywhere in the human body, explaining the wide range of symptoms that SARS-CoV-2 can cause.
Viral persistence is a possible cause of Long COVID, and given the widespread distribution of the ACE2 receptor, we should expect a diversity of long-term impacts. These can range from persistent fever in children to new onset hypothyroidism in adults, and from the development of diabetes to acute kidney injury.
When a coronavirus infects a cell, it usually destroys the cell as part of replication, or the cell is destroyed by the immune system. This destruction causes damage to the affected organ. In some cases, the virus continues to persist, driving an ongoing immune response. Considering the widespread distribution of the ACE2 receptor and the mechanisms by which SARS-CoV-2 can cause damage, it is not surprising that the risk of developing long-term symptoms increases with each reinfection.
With the rapid mutation rate of SARS-CoV-2, reinfection is likely to be relatively common. If the results of the NIH study hold true for subsequent infections, we should not be surprised to observe a cumulative risk of long-term harm with each instance of COVID-19.
In the face of this ongoing threat, it's crucial to stay informed and take measures to reduce the risk of catching or transmitting COVID-19. The fight against this pandemic is far from over, and we must continue to prioritize public health and safety.