Prevalence and difference of COVID-19 symptoms, post-COVID conditions and duration of illness among the vaccinated and unvaccinated population: a cross-sectional study in Peshawar

Background:Studies on coronavirus disease 2019 (COVID-19) symptoms, post-coronavirus disease (COVID) conditions, and vaccination outcomes in Pakistan are limited and inconsistent. The study investigated differences in symptoms and post-COVID conditions between vaccinated and unvaccinated individuals and the impact of vaccination on illness duration based on existing literature. Methods:The study was a 3-month cross-sectional study conducted in Peshawar, Pakistan. It targeted individuals aged 16 and above who had contracted COVID-19 at least once during the recent pandemic, regardless of gender, and confirmed through reverse transcriptase polymerase chain reaction testing. The sample size was 250, determined using the WHO sample size calculator. Data were collected through questionnaires after obtaining verbal consent and analyzed using IBM SPSS version 26, taking into account their vaccination status along with other important variables. Results:Among the 250 respondents, 143 (57.2%) were unvaccinated, while 107 (42.8%) were vaccinated at the time of contracting COVID-19. Unvaccinated subjects developed a greater variety of symptoms that lasted for longer durations (P<0.001) with symptoms like dyspnea [55 (38.5%, P=0.011)], anosmia [76 (53.1%, P=0.001)], and chest pain [24 (16.8%, P=0.029)] occurring at greater percentages. Sixty-one (42.7%) unvaccinated subjects reported post-COVID conditions as opposed to 29 (27.1%) among the vaccinated group [P=0.011; odds ratio (OR)=0.5; 95% CI=0.29-0.86]. Conclusion:The study found that COVID-19 vaccination can reduce the duration and frequency of symptoms, as well as post-COVID conditions. This is the first research of its kind conducted in Peshawar, Pakistan, and may serve as a foundation for future research in this demographic.