ABSTRACT
Introduction Military forces around the world face an increased risk of the spread of communicable diseases, due to the close living quarters and congregated nature of the military camps. The Singapore Armed Forces (SAF) implemented a multi-pronged surveillance and containment strategy to reduce the risk of a coronavirus disease 2019 (COVID-19) outbreak within the local military camps. This paper details the epidemiological investigations of the COVID-19 cases in the SAF and highlights the strategies and public health measures undertaken, aligned with the national COVID-19 control strategy, to reduce the risk of COVID-19 transmission in the military camps. Materials and Methods Medical data of our military personnel who were infected with COVID-19 during the first 180 days of the pandemic were extracted from the military electronic health records. Contact tracing and activity mapping results were obtained from unit-level epidemiological data. A review of the organization's response plans, instructions, and orders was conducted to collate the measures implemented across the same time period. Results Prompt contact tracing and activity mapping was done for each of the 24 SAF military personnel diagnosed with COVID-19 between February 2020 and June 2020, with possible links among the cases identified and investigated. Conclusion A combination of strategies in the formulation of public health measures based on key principles of early warning and surveillance, prompt diagnosis, and early containment were successful in preventing the formation of COVID-19 clusters within the SAF. This will provide a framework for the management of future pandemics within the military setting, driven by strong governance and leadership, to meet the military's need to maintain operational readiness in a safe manner.
ABSTRACT
INTRODUCTION: The use of novel mRNA platforms for COVID-19 vaccines raised concern about vaccine safety, especially in Asian populations that made up less than 10% of study populations in the pivotal vaccine trials used for emergency use authorisation. Vaccine safety issues also remain a concern in assessing the clinical risks and benefits of vaccine boosters, particularly in specific age groups or segments of the population. This study describes a vaccination exercise involving Asian military personnel, and the adverse reactions and safety events observed. METHODS: Minor adverse reactions, hospitalisations and adverse events of special interest were monitored as part of the organisation's protocol for safety monitoring of COVID-19 vaccinations. All vaccine recipients were invited to complete an online adverse reaction questionnaire. Medical consults at the military's primary healthcare facilities were monitored for vaccine-related presentations. All hospitalisations involving vaccine recipients were analysed. Adverse reaction rates between doses, vaccines and age groups were compared. RESULTS: A total of 127,081 mRNA vaccine doses were administered to 64,661 individuals up to 24 July 2021. Common minor adverse reactions included fever/chills, body aches and injection site pain. These were more common after dose 2. Younger individuals experienced minor adverse reactions more frequently. Rare cases of anaphylaxis, Bell's palsy and myocarditis/pericarditis were observed. No deaths occurred. CONCLUSION: Minor adverse reactions were less common than reported in other studies, and rates of anaphylaxis, Bell's palsy and myocarditis/pericarditis were comparable. Our study supports the favourable safety profile of mRNA COVID-19 vaccines, which may help guide decisions about booster doses if required.