Effect of COVID-19 vaccine on long-COVID: A 2-year follow-up observational study from hospitals in north India

Abstract

Introduction: Long-COVID syndrome encompasses a constellation of fluctuating, overlapping systemic symptoms after COVID. We know that vaccination reduces the risk of hospitalization and death but not of re-infections. How these vaccines impact long-COVID is under debate. The current study was designed to analyze the patterns of long-COVID amongst vaccinated and unvaccinated hospitalized patients during the three waves in India. Methods: The computerized medical records of the patients admitted to a group of hospitals in the National Capital Region of Delhi with a nasopharyngeal swab positive RT-PCR for SARS-CoV-2, during the three distinct COVID-19 waves, were accessed. Because of large numbers, every 3rd case from the data sheet for the wave-1 and wave-2 but all cases admitted during wave-3 were included because of small numbers (total 6676). The selected patients were telephonically contacted in April 2022 for symptoms and their duration of long-COVID and their vaccination status. Of these, 6056 (90.7%) responded. These were divided into fully vaccinated who received both doses of COVID vaccine at least 14 days before admission (913) and unvaccinated at the time of admission (4616). Others and deaths were excluded. symptom-weeks was calculated as the sum of weeks of symptoms in case of two or more symptoms. The statistical significance was tested, and odds ratio (unadjusted and adjusted) were calculated by logistic regression. Results: Nearly 90% of COVID-19 patients reported at least one symptom irrespective of their vaccination status. Almost three-fourths of these had symptoms lasting up to a month but nearly 15% reported a duration a least 4 weeks including 11% even exceeding one year. During wave-3, significantly more vaccinated patients reported short term post-acute sequelae of COVID-19 than did the unvaccinated group. The cases with diabetes and hypertension had higher odds of reporting at least one symptom when the effect of vaccination, age, sex, severity, and length of stay was adjusted. The fully vaccinated cases had reduced length of stay in the hospital and had a milder disease. Most common symptoms reported by both the groups were fatigue (17.0%), insomnia (15.1%) and myalgia (15%). There were significant differences in the duration and the type of long-COVID symptoms across the three waves, and the presence of comorbidities between the vaccinated and the unvaccinated groups but overall no difference could be detected. No significant difference was seen between the cases receiving covishield and covaxin. Conclusions: Nearly 15% reported symptoms of duration exceeding 4 weeks including 11% exceeding one year. There were significant differences in the specific symptoms with some more common in the vaccinated and some others more common in the unvaccinated but overall the vaccination or the type of vaccine did not significantly alter either the incidence or the duration of long COVID.

Effect of COVID-19 Vaccines on Reducing the Risk of Long COVID in the Real World: A Systematic Review and Meta-Analysis

“…The main information and the data for the meta-analysis of the included studies are shown in Table 1 and Table S2 of the Supplementary Material, respectively. Among them, 15 articles were accepted or published [15,16,[21][22][23][24][25][26][27][28][29][30][31][32][33]] and 3 articles were preprints [7,34,35]. All of the studies were observational, including 12 cohort studies, 1 case-control study, and 5 cross-sectional studies.…”

Impairments following COVID-19 infection: Manifestations and investigations of related factors

“…This nding is in line with previous studies showed that the risk of post-COVID complaints are differed as function of vaccinate status. In that, post-COVID complaints are more common in non-vaccinated individuals compared to vaccinated individuals 45,47,48,49,50,51,52,53 . In the current study, been hospitalized didn't contribute to the explained variances in post-COVID impairments.…”

Real-world Effectiveness and Causal Mediation Study of BNT162b2 on Long COVID Risks in Children and Adolescents

“…Some studies suggest a significant protective effect [18][19][20][21][22][23][24][25][26][27] , e.g., a reduced risk of the diagnosis of PASC or experiencing certain PASC symptoms. Meanwhile, other studies indicate mixed effects revealing considerable variations across different age groups, various dominant virus strains, and distinct PASC symptoms [28][29][30][31][32] , or even suggesting counter-protective effects 33,34 . Moreover, the majority of existing studies have reported effects by comparing breakthrough infection to infections in unvaccinated individuals, which is conditional on the infection status 18,21,24,26,28,29,35 .…”