Identification of Anthrax as the Cause of a Cluster of Unexplained Deaths, Uganda, 2023: The Role of Metagenomic Next-Generation Sequencing and Postmortem Specimens.

Abstract

Between April and November 2023, 27 unexplained human deaths that presented with swelling of the arms, skin sores with black centers, difficulty in breathing, obstructed swallowing, headaches, and other body aches were reported in Kyotera District, Uganda by the Public Health Emergency Operations Center. Subsequently, the death of cattle on farms and the consumption of carcass meat by some residents were also reported. Field response teams collected clinical/epidemiological data and autopsy samples to determine the cause of deaths. Metagenomic next-generation sequencing (mNGS) and target enrichment sequencing conducted on postmortem samples confirmed Bacillus anthracis, the etiological agent of anthrax disease, as the cause of the deaths. Applying mNGS to autopsy specimens is useful as a retrospective tool for identifying high-consequence pathogens during suspected outbreaks of unknown etiology.