What is the impact of pre-COVID vaccinations on long COVID?

Two years later, the coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to impact the lives of people around the world. The World Health Organization (WHO) reports that worldwide he has more than 617 million confirmed cases and more than 6.5 million deaths linked to her COVID-19.

Several studies have shown the development of acute sequelae of SARS-CoV-2 infection (PASC) weeks after SARS-CoV-2 infection. Long COVID is a broad term used to define the ever-changing symptoms of PASC.

Background

Most studies have observed that vaccines are effective and safe in reducing the risk of severe COVID-19. However, the long-term effects of COVID are not fully understood. Some studies show that vaccines have protective effects, while others report mixed or anti-protective effects.

New research posted on preprint server medrex sib*Intended to analyze the impact of pre-COVID-19 vaccination on long-term diagnosis of COVID.

About research

This study was part of the National Institutes of Health (NIH), which developed the RECOVER initiative to treat, understand, and prevent PASC. All analyzes in this study were performed within the National COVID Cohort Collaborative (N3C) enclave, which uses electronic health records (EHRs) to obtain patient data. The dates of the COVID-19 Index were determined according to the earliest signs of COVID-19 infection.

Inclusion criteria for study inclusion included either International Classification of Disease-10-Clinical Modification (ICD-10) COVID-19 diagnostic code or SARS-CoV-2 antigen OR PCR test with a health care visit recorded between 120 and 300 days from index, completed vaccination status on index or not started vaccine regimen, 18 years of age or older on index, and at least 2 Index previous year with number of recorded health care visits.

In addition, vaccination coverage at each health facility was calculated by the ratio of the observed proportion of patients with vaccination records and the expected vaccination coverage obtained from CDC reports. Only sites where the observed rate was at least two-thirds of the expected vaccination rate were included in the study.

Individuals who completed the vaccination regimen prior to the index were considered vaccinated, others were considered unvaccinated. The ICD-10 code for post-COVID-19 condition (U09.9), the ICD-10 code for prolonged visits to his COVID clinic, and the outcome of other parasites and infections (B94). .8). Finally, the model was used to calculate the long-term COVID score for each patient, ranging from 0 to 1, and to classify patients with scores >0.9 as long-term COVID.

Survey results

Results showed a protective association between long-term COVID and vaccination status in model- and clinic-based cohorts. Protective associations were observed to remain consistent among those subsequently infected with COVID-19 and those requiring clinical diagnosis.

It was also observed that individuals with model scores between 0.6 and 0.9 exhibited some symptoms of long COVID.

Current research therefore indicates that vaccination is an important tool to combat COVID-19. Pre-COVID vaccination was observed to retain protective effects against long-term COVID, even with breakthrough infections.

Limitations

This study has certain limitations. First, the study relies on her EHR and other factors, so it may not be completely accurate. Second, the study did not distinguish between vaccine types. Third, the implementation of ICD10 code U09.9 was not made until October 2021. Finally, model-based cohorts may contain misclassification of COVID long-term outcomes.

*Important Notices

medrex sib We publish a non-peer-reviewed, preliminary scientific report and should not be taken as conclusive, to guide clinical practice/health-related actions, or to be treated as established information.