Adverse effects Associated with Third-Booster COVID-19 Vaccine (Heterologous Vaccines by Sinovac- Moderna) among Health Care Workers

The mRNA 1273 vaccine by Moderna©has recorded to be94.1% effective against laboratory-confirmed Covid-19 infection. Health care workers in Indonesia are receiving third-booster vaccine by Moderna after the two doses of virus-inactivated vaccine. Further evaluation of Covid-19 mRNA vaccine post-injection effects on health care workers is necessary. This present study asssessed the post-immunization adverse events tohealth care workersin the Port Health Office of Semarang.This was a retrospective, cross-sectional, observational study aimed to the HCWs, both staff and non-staff, of the Port Health Office of Semarang.We identified and analyzed the adverse effects on 132 workers who had been receiving third-mRNA booster vaccine by Moderna. About 37.8% (50 out of 132)respondents experienced adverse events after receiving third-booster vaccine by Moderna. Among them, female workers (62%) had more incidents compared to males (38%). the most common symptoms were localized painon injected arm (100%), fatigue (44%), fever (42%), myalgia (38%), and chills (30%). Other symptoms like night sleep issue, diarrhea, nausea, an headacheswere also reported.The mRNA 1273 vaccine by Moderna©injection as booster provides several severe but not life-threatening symptoms, most of the emerging cases are fatigue and fever and and possibly correlated with gender.