Burden of COVID-19 and Case Fatality Rate in Pune India: An Analysis of First and Second Wave of the Pandemic

Background The recent second wave in India in April-May 2021 placed an unprecedented burden on the Indian health systems. However, limited data exist on the epidemiology of the COVID-19 pandemic from the first wave through the second wave in India. With detailed epidemiologic data, we aimed to assess trends in incident cases and case fatality, its risk between pandemic waves in Pune, an epicenter of COVID-19 cases in India, a country with the second-largest absolute burden worldwide. Methods Programmatic COVID-19 data from Pune city between the first wave (March 09th 2020-October 31st, 2020), maintenance phase (November 01st 2020-February 14th, 2021), the second wave (February 15th, 2021-May 31st, 2021) were assessed for trends of incident cases, time-to-death, and case fatality rate (CFR). In addition, Poisson regression models adjusted for age and gender were used to determine the independent effect of pandemic waves on mortality. Results Of 465,192 COVID-19 cases, 162,182 (35%) were reported in the first wave, and 4,146 (2.5%) died among them; Maintenance period registered 27,517 (6%) cases with 590 (2.1%) deaths; Second wave reported 275,493 (59%) cases and 3184 (1.1%) deaths (p<0.01). The overall CFR was 1.16 per 1000 person-days (PD), which declined from 1.80 per 1000 PD during the first wave to 0.77 per 1000 PD in the second wave. The risk of death was 1.49 times higher during the first wave (adjusted case fatality rate ratio-aCFRR,1.49; 95% CI: 1.37–1.62) and 35% lower in the second wave (aCFRR, 0.65; 95% CI: 0.59 – 0.70), compared to the maintenance phase. Interpretation The absolute burden of COVID-19 cases and deaths were more significant in the second wave in Pune, India; however, the CFR declined as the pandemic progressed. Nevertheless, investigating newer therapies and implementing mass vaccinations against COVID-19 are urgently needed. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This analysis was done as part of the Pune Knowledge Cluster (PKC) comprising Pune-based academics, academic institutions, and industry partners. The PKC principal investigators, Dr. LS Shashidhara and Dr. Ajit Kembavi received funding support from Pune Knowledge Cluster Initiative under the Government of India. This study was not funded separately. This paper's content is solely the authors' responsibility and does not necessarily represent the official views of the PKC or its funder. ### 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: The Indian Institute of Science Education and Research ethics committee, Pune, India, approved this analysis of the public health monitoring program. All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived. 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 Data will be available upon a relevant request