COVID-19 pandemic indicators and variation with vaccinations in Malaysia: a regional-based geo-visualization and geo-ecological regression study

Our objective was to study the impact of vaccinations on COVID-19 pandemic indicators across different regions of Malaysia. We collected population-level pandemic data from government open sources from 1 January 2021 until 30 June 2022. The aggregated data was then analysed by rates for vaccinations, infections, hospital admissions, intensive care unit (ICU) admissions, and case fatalities according to five regions in Malaysia. From the cumulative data, a total of 4,456,066 COVID-19 cases that contributed to 489,210 hospital admissions, 292,897 ICU admissions, and 35,378 deaths were operationalized to regional-levels, coherently stratified by pandemic-control measures. Vaccination rates were computed based on the proportion of people within each region who completed their primary doses (27,275,616 people) and booster shots (16,230,989 people). Geographic visualizations, ecological correlations, and ordinary least squares (OLS) regressions for statistically significant effect quantification were synthesized. Region-specific geo-visualization using choropleth maps confirmed that the indicators of the pandemic were effectively controlled with vaccinations. It was observed that a percent increase in vaccination rates resulted in a significant decrease in the rates of infections, hospital admissions, ICU admissions, and case fatalities. This reduction in pandemic indicators was greater in populations with higher booster vaccination rates across the country. However, the magnitude effect of those suppression coefficients as explained by the populations' vaccination showed different gradients and varying consistencies, indicating the influence of geographical variations and pandemic control measures in different regions. Vaccinations were largely effective in reducing pandemic indicators but were not powered to halt or zero them. Trend reductions varied by regions and by pandemic control measures in place, suggesting that interventions for pandemic control are highly influenced by geographical contexts, coexistent with a certain degree of sustained mitigation strategies.