How has the incidence of long-COVID changed over the course of the corona pandemic? What role does the evolution of SARS-CoV-2 play in this, and what importance does the vaccines play?
New ones keep popping up The type of the Coronavirus on. The symptoms that the new variants cause are similar to those known from the pandemic period. And some infected people still develop post-acute COVID-19 syndrome (PASC), also known as Long COVIDwhich can affect various organ systems.
The risk of developing Long COVID probably depends, among other things Severity the infection, the Pre-existing conditions the patient and the Vaccination status away. It can also be assumed that changes over time during the pandemic, such as: Evolution of SARS-CoV-2, have an influence on the long COVID risk.
In a study, a US research team is this connections followed up. For their work, the group used data from the Health records from the Department of Veterans Affairs. The study population included a total of 441,583 former soldiers who were infected with SARS-CoV-2 between March 1, 2020 and January 31, 2022, as well as 4,748,504 uninfected control subjects. The study authors estimated the cumulative incidence of Long COVID one year after infection during the pre-delta, delta and omicron phases COVID-19-Pandemic ab.
In unvaccinated people with SARS-CoV-2 infection, the cumulative incidence of Long COVID in the first year after infection was 10.42 events per 100 people in the Pre-delta phase. Thereafter there was a decrease in the incidence to 9.51 events in the Delta-Phase and 7.76 events per 100 people in the omicron phase. In vaccinated people with SARS-CoV-2 infection, the cumulative incidence of Long COVID after one year was 5.34 events during the delta phase and 3.50 events per 100 people during the omicron phase.
The likelihood of long-term consequences decreased
Compared to unvaccinated people, the cumulative Incidence of Long COVID in this patient group at both points in time lower. The difference was 4.18 events per 100 people in the delta phase and 4.26 events per 100 people in the omicron phase.
Within the framework of so-called Decomposition analyses The scientists also investigated the question of why the cumulative incidence in the omicron phase was lower than in the pre-delta and delta phases combined. They concluded that this effect was 28% due to the changes in the virus and almost 72% due to the introduction of the Vaccines attributed is.
Sources:
1. Xie Y et al. N Engl J Med 2024; 391:515-525; DOI: 10.1056/NEJMoa2403211
2. Rosen CJ. N Engl J Med 2024; 391: 561-562; DOI: 10.1056/NEJMe2407575
