Anthrax toxins-producing Bacillus spp. isolated from handwashing stations during COVID-19 pandemic in Lagos, Nigeria

Abstract

Introduction: The virulence binding factor, protective antigen (pag) and poly-D-γ-glutamate capsular (cap) genes, peculiar to Bacillus anthracis are located in the pXO1 and pXO2 plasmids which are transferable horizontally to related species called “cereus group”. The cereus group are usually isolated from the environmental/food samples and have been implicated in debilitating human and animal anthrax-like diseases. This study was designed to investigate the presence of the anthrax virulence genes in different Bacillus spp. isolated from handwashing facilities during COVID-19 pandemic in Lagos, Nigeria. Methodology: The Bacillus anthracis (OK316847), B. thuringiensis (OK316855), B. amyloliquefaciens (OK316857), B. cereus (OK316858) and B. thuringiensis (OK316859) previously isolated from rinsates and bowl water in two local government areas (LGAs) of Lagos state were further investigated by the polymerase chain reaction (PCR) amplification of the pag and cap genes using specific primers. Results: Bacillus anthracis and B. cereus co-harboured the two 578 bp cap and 364 bp pag genes while B. thuringiensis only harboured the cap gene. Similarly, the non-cereus B. amyloliquefaciens was found to habour the pag gene. Conclusions: The two anthrax toxin genes were amplified in the Bacillus spp isolated from rinsates and bowl water used in hand washing in the two study LGAs. Given that these virulence genes have a global consequence and are a potential threat to life, this study calls for an extensive surveillance, and reassessment of gene regulators and plasmid distribution among these strains in our environment.