India witnessed three COVID-19 pandemic waves, each with various degrees of severity and clinical signs. The coronavirus strain and immunization status have a significant impact on the severity of COVID-19 infections. The current study intends to evaluate and compare the symptoms, severity, and breakthrough infections in vaccinated and unvaccinated individuals over the three waves of the pandemic.
This was a retrospective survey study. A Google based questionnaire was used to collect data on demographics, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection status, re-infections, associated symptoms, severity, and vaccination status over three waves, post-COVID-19 sequelae, and willingness to receive a COVID-19 booster dose in the Indian population. The replies of 3,404 Indian participants were analysed using STATA 11.
Each wave showed a decrease in the number of symptomatic COVID-19 infections. However, fever and loss of smell/taste were identified as the most common symptoms in each wave. Clinical symptoms such as fever, weariness, and shortness of breath were shown to be considerably higher in vaccinated than unvaccinated individuals. The number of SARS-CoV-2 breakthrough infections increased between the second and third waves. Approximately 36.5% of people with protracted COVID-19 had previously received immunization after recovering from a natural COVID-19 illness. Overall, 34.8% of individuals were hesitant to take the COVID-19 booster dose.
Increased symptoms in vaccinated individuals during the second wave, emphasizing the potential role of antibody-dependent augmentation. A considerable fraction (36.5%) of those with protracted COVID-19 infections had previously received vaccination after contracting the virus naturally. The fact that vaccine received after COVID-19 infection has been shown to be a risk factor for long-term COVID-19 emphasizes the need for vigilance in this specific subgroup.