Impact of COVID-19 Vaccinations in India - A Statewise Analysis

Objective The COVID-19 vaccination program in India started after the first wave of infections had almost subsided. In this work, the objective is to perform a statewise analysis to assess the impact of vaccination during the second COVID-19 wave in India. A total of 21 states are chosen for the analysis encompassing 97% of the Indian population. Methods We use the generalized Gompertz curve to study the COVID-19 outbreak. The generalized Gompertz model is then modified to study the impact of vaccination. The modified model considers the cumulative daily number of individuals having the first and second shots of the vaccine in each state as explanatory variables. Results We observe that, out of 21 states, 16 states show the effectiveness of vaccines in curbing the spread of COVID-19. However, in states like Telangana, West Bengal, Tamil Nadu, Rajasthan, and Kerala, we do not conclusively observe the impact of vaccination during the study period. Conclusions The effectiveness of COVID-19 vaccine depends on many factors. Some of them are not directly measurable. Using only COVID-19 infection cases and the vaccination data, we conclude that overall the vaccination program was effective in curbing the spread of COVID-19 in India. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement Palash Ghosh would like to acknowledge support by the ICMR Centre for Excellence, Grant no. 5/3/8/20/2019-ITR. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: All data used are available online. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes The updated data on infections can be downloaded from \url{www.kaggle.com/datasets/vinitshah0110/covid19-india?resource=download }, and the statewise data on vaccinations is available at \url{www.kaggle.com/datasets/harveenchadha/india-covid19-vaccination-data?select=vaccination.csv}