German study shows extent of long COVID

After more than two and a half years of the COVID-19 pandemic and thanks to various vaccines that have been available since the beginning of 2021, the fear of infection with SARS-CoV-2 has now given way to acceptance among large parts of the population. However, the fact that even people who have hardly any or only mild symptoms of acute COVID-19 disease can subsequently experience long-term impairments – also known as long COVID – cannot be denied. A recent publication shows the extent to which long COVID affected people in Germany who contracted SARS-CoV-2 between October 2020 and March 2021 [1].

Every third person suffers from fatigue and neurocognitive limitations after more than 6 months

There are still relatively few large-scale studies on long COVID that deal with the consequences of acute COVID-19 illness beyond the period of 6 months. The German EPILOC study therefore collected data on symptoms and symptom clusters 6-12 months after infection as well as on risk factors and examined the extent to which the affected persons’ general health status and ability to work were impaired [1]. A total of 50,457 adults aged 18 to 65 years from southern Germany who had their SARS-CoV-2 infection confirmed by PCR were invited to participate. The response rate was 24%, with the responses of 11,710 individuals being sufficiently meaningful to be included in the analysis. It turned out that the symptom clusters of fatigue with 37.2% and neurocognitive impairments with 31.3% contributed the most to reduced health and ability to work. Other symptom clusters of high relevance for well-being and ability to work were chest pain, anxiety/depression, headache/dizziness, and pain syndromes. Overall, the study estimated that 28.5% of the participants suffered from long COVID, although selection and recall biases cannot be ruled out. Risk factors for certain symptom clusters have been shown to include severity of acute illness, female gender, higher body mass index, current smoking status, and increasing age. However, the team of authors emphasises that younger people with mild acute infections were also affected by significant impairments [1].

COVID-19 vaccination with at least two vaccine doses reduces long COVID risk

While the EPILOC study mainly included unvaccinated individuals due to the time period covered, a recent systematic review addressed the question of whether vaccinations affect the risk of long COVID [2]. After applying the study selection criteria, 15 international studies were considered, which included a total of 185,689 vaccinated and 759,987 unvaccinated participants. The statistical evaluation of the pooled data showed that the risk of long COVID in vaccinated (at least two doses) was 29% lower than in unvaccinated persons. Interestingly, even vaccination AFTER infection reduced this risk [2]. Vaccination thus appears to not only protect against severe disease, hospitalisation and death, but also to some extent against long COVID.

STIKO recommends Omicron-adapted bivalent mRNA vaccines as boosters

While currently available study results on vaccination protection are still based on the "old" vaccines, omicron-adapted bivalent mRNA vaccines have also been approved in the EU since September 2022. For example, Germany's Standing Committee on Vaccination (STIKO) now recommends these vaccines for booster vaccinations from the age of 12 on [3], and most European countries will probably proceed in a similar way. Even though not enough clinical data on a possible higher effectiveness are available yet, it can be hoped that the adapted vaccines will also provide better protection against infection – which would be gratifying in view of the upcoming winter season!

Sources:

1. Peter RS et al. (2022) Post-acute sequelae of covid-19 six to 12 months after infection: population based study. BMJ 379: e071050. https://doi.org/10.1136/bmj-2022-071050
2. Gao P et al. (2022) Effect of COVID-19 Vaccines on Reducing the Risk of Long COVID in the Real World: A Systematic Review and Meta-Analysis. Int J Environ Res Public Health 19: 12422. https://doi.org/10.3390/ijerph191912422
3. Paul-Ehrlich-Institut (2022) Latest News - 11 October 2022 - COVID-19-Vaccines. https://www.pei.de/EN/service/press/latest-news/latest-news-content.html?nn=303330 (accessed on October 31, 2022)