Estimation of excess all-cause mortality due to COVID-19 in Thailand

Thailand has experienced the most prominent COVID-19 outbreak, resulting in a new record for COVID-19 cases and deaths in 2021. To assess the influence of the COVID-19 outbreak on mortality, we estimated excess all-cause and pneumonia mortality in Thailand during the COVID-19 outbreak from April to October 2021. We used the previous five years’ mortality to estimate the baseline number of deaths using generalized linear mixed models (GLMMs). The models were adjusted for seasonality and demographics. We found that the estimated cumulative excess death was 14.3% (95% CI: 8.6%-18.8%) higher than the baseline. The results also showed that the excess deaths in males were higher than in females by approximately 26.3%. The excess deaths directly caused by the COVID-19 infections accounted for approximately 75.0% of the all-cause excess deaths. Furthermore, excess pneumonia deaths were also found to be 26.2% (95% CI: 4.8%-46.0%) above baseline. There was a significant rise in excess fatalities, especially in the older age groups. Therefore, the age and sex structure of the population are essential to assessing the mortality impact of COVID-19. Our modeling results could potentially provide insights into the COVID-19 outbreaks and provide a guide for outbreak control and intervention.