Control Strategies for the COVID-19 Infection Wave in India: A Mathematical Model Incorporating Vaccine Effectiveness

The waning effectiveness of the coronavirus disease-2019 (COVID-19) vaccines and the emergence of new variants have given rise to the possibility of future outbreaks of the infection. COVID-19 has caused more than 43 million reported cases and 526,000 deaths in India so far, and the disease spread is active again despite mass vaccinations. In this article, we present a compartmental epidemiological model incorporating vaccinations with dose-dependent effectiveness. We study a possible sudden outbreak of SARS-CoV2 variants in India, bring out the associated predictions for various vaccination rates, and point out optimum control measures. Our model simulation numbers for the total infected are close to the seroprevalance data in August 2021, and our results show that second dose vaccine effectiveness is the most sensitive parameter in the future evolution of the disease. A combination of vaccination and social distancing is the key to tackling the current situation and for the coming few months. Our simulation shows that social distancing measures show better control over disease spread than higher vaccination rates, and disease spread does not appear to rise sharply in the near future unless a new variant emerges.