Predicting COVID-19 Mortality Risk Across SARS-CoV-2 Variants in Malaysia: A Three-Year Retrospective Study

Abstract ID: 188

Authors:
MOHAMAD NASRI MOHAMAD ISA
NUR AFIQAH MOHD SALLEH

Affiliations:
Universiti Malaya.

Abstract:Background: As of March 2023, over 761 million COVID-19 cases and 6.8 million deaths have been reported globally. Malaysia recorded over 5 million cases and 30,000 deaths within the same period. The emergence of SARS-CoV-2 variants with differing transmissibility, virulence, and immune escape properties has complicated pandemic control. This study investigates variant-specific mortality risk factors to support health system preparedness in future outbreaks in Malaysia. Methods: This retrospective ecological study utilized secondary surveillance data of confirmed COVID-19 cases reported in Melaka, Malaysia, from March 2020 to March 2023. Data were obtained from the Melaka State Health Department and included cases with confirmed SARS-CoV-2 variants. The collected variables included sociodemographic characteristics, comorbidities, clinical symptoms, vaccination status, and outcomes. A universal sampling method was applied, and the data were analysed using SPSS software. Descriptive statistics were used to summarize case characteristics, followed by univariate and multivariate logistic regression analyses to identify factors independently associated with COVID-19 mortality Results: Among 1,146 cases, the mean age was 48.2 years (±22.6 years), and 52.1% of the cases were male. Omicron was the most common variant (86.8%). Most cases were symptomatic (89.6%) and had at least one comorbidity (54.7%), with the most common conditions being hypertension (31.2%) and diabetes mellitus (24.1%). The overall mortality rate was 2.9%. Multivariate analysis identified several factors significantly associated with death: Delta variant infection (OR=3.43, 95% CI: 1.07 11.03), age <¥65 (OR=2.66, 95% CI: 1.13 6.24), unvaccinated status (OR=4.36, 95% CI: 1.58 12.04), and shortness of breath (OR=4.39, 95% CI: 2.01 9.62). Conclusions: This study highlights the elevated mortality risk associated with the Delta variant, advanced age, being unvaccinated, and respiratory distress. These findings underscore the importance of targeted vaccination, early identification of high-risk individuals, and adaptive health system planning to improve responses to future variant-driven outbreaks.

Keywords: Health Systems and Universal Health Coverage (UHC), COVID-19, SARS-CoV-2 variants, mortality, Melaka, epidemiology, health system preparedness