Real world performance of inactivated SARS-CoV-2 vaccine (CoronaVac) against infection, hospitalization and death due to COVID-19 in adult population in Indonesia

Background Inactivated SARS-CoV-2 vaccine has been included in the national COVID-19 vaccination program in Indonesia since January 2021. The study aims to assess the impacts of inactivated COVID-19 vaccine on infection, hospitalization, and death among adult population aged ≥18 years in Bali, Indonesia. Methods Test-negative, case control study was conducted by linking SARS-CoV-2 laboratory records, vaccination, and health administrative data for the period of January 13 to June 30, 2021. Case-subjects were defined as individuals who had a positive RT-PCR test for SARS-CoV-2 during the period; they were matched with controls (tested negative) (1:1) based on age, sex, district of residence, and week of testing. We estimated the odds of vaccination in PCR confirmed, hospitalization and death due to COVID-19, accounting for the presence of comorbidities and prior infection. Vaccine effectiveness was estimated as (1-odds ratio) x 100%. Results Total 109,050 RT-PCR test results were retrieved during the January 13 to June 30, 2021. Of these, 14,168 subjects were eligible for inclusion in the study. Total 5518 matched case-control pairs were analyzed. Adjusted vaccine effectiveness (VE) against laboratory-confirmed SARS-CoV-2 infection was 14.5% (95% confidence interval -11 to 34.2) at 0-13 days after the first dose; 66.7% (95% CI: 58.1-73.5) at ≥14 days after the second dose. The adjusted effectiveness against hospitalization and COVID-19-associated death was 71.1% (95% CI: 62.9-77.6) and 87.4% (95% CI: 65.1-95.4%) at ≥14 days after receiving the second dose, respectively. Conclusions Two-dose of inactivated CoronaVac vaccine showed high effectiveness against laboratory confirmed COVID-19 infection, hospitalization, and death associated with COVID-19 among adults aged ≥18 years. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study was funded by the National Institute of Health Research and Development, Ministry of Health, Indonesia. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The views expressed in this publication are those of the authors and not necessarily those of the Ministry of Health of Indonesia. ### 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: Health Research Ethics Committee of National Institute of Health Research and Development, Ministry of Health, Indonesia gave ethical approval for this work 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 datasets used and/or analyzed during the current study are protected by the Ministry of Health of Indonesia and are unsuitable for public sharing. Interested parties can apply for the data by contacting the data center of the Ministry of Health of Indonesia. All data generated or analyzed during this study are included in this published article (and its Supplementary information files). Aggregate data on vaccination and COVID-19 incidence are publicly available at