This is a report of 8-months progression of circulating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants in Brunei Darussalam from November 2021. Whole-genome sequencing (WGS) was performed on nearly 3,000 random local COVID-19 patients in samples with a cycle-threshold (CT) of less than 25. Phylogenetic analysis revealed that the Delta variant, particularly AY.24.1, was the predominant variant towards the end of 2021. The same variant was then completely superseded by the Omicron variants in mid-January 2022. During the early wave of Omicron variants, BA.2.3.19 and its paternal BA.2.3 were found to be the prominent sublineage until it was replaced by BA.5 lineages four months later, mainly BA.5.2 and BF.5. Further analysis revealed that AY.24.1 and BA.2.3.19 that was once a prevalent variant are predominantly observed in Brunei. Both variants can be differentiated by the presence of a particular mutation in the S gene that encodes the viral spike protein that is essential for host cell interaction. Brunei is continuously monitoring the circulating SARS-CoV-2 variants as part of its genomic surveillance following the World Health Organization (WHO) guidance for surveillance.

Mycobacterium africanum is endemic to West Africa and is rare outside this region. Most of the people infected with M. africanum outside Africa are migrants from affected parts of Africa. We report a rare case of pulmonary tuberculosis (TB) secondary to M. africanum in a man in Brunei Darussalam who had lived and worked in Guinea, West Africa for 6 years more than 20 years ago. He had been well until December 2020, when he presented with a chronic cough and was diagnosed with coinfections of Klebsiella pneumoniae and M. africanum, and newly diagnosed diabetes mellitus. This case highlights an interesting manifestation of pulmonary TB secondary to M. africanum in a patient whose last exposure was 20 years ago, contributed to by development of diabetes mellitus.