# Emergence of Human and Animal Melioidosis in Southern Africa, 2018–2021

## TL;DR

Melioidosis, a serious bacterial infection, has been identified for the first time in Southern Africa, highlighting the need for better surveillance and diagnostics.

## Contribution

First reported cases of melioidosis in humans and animals in Southern Africa, revealing the bacterium's long-term cryptic presence.

## Key findings

- Three human and two animal cases of melioidosis were identified in South Africa and Namibia between 2018 and 2021.
- Genomic analysis showed substantial diversity, indicating long-term persistence of Burkholderia pseudomallei in the region.
- Limited awareness and diagnostic capacity likely contribute to the disease's underreporting in Southern Africa.

## Abstract

Melioidosis is increasingly recognised in tropical and subtropical regions worldwide as a serious and potentially fatal bacterial infection affecting humans and animals, acquired from the environment. Until now, human cases of melioidosis had not been reported in Southern Africa. Over a four-year period, we identified three human and two animal cases of melioidosis in South Africa and Namibia. Burkholderia pseudomallei isolates were investigated by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) and whole-genome sequencing (WGS). Phylogenetic analysis demonstrated substantial diversity, suggesting long-term cryptic persistence of the bacterium in the Southern African region. Limited awareness of the disease and inadequate diagnostic capacity likely contribute to its apparent rarity in the region. These findings underscore the urgent need for increased surveillance, improved diagnostics, and greater awareness of melioidosis in Southern Africa to better understand its true epidemiological burden and prevent future cases.