Mycobactéries et eau

The Mycobacterium genus comprises Mycobacterium tuberculosis complex, M. leprae and nontuberculous mycobacteria (NTM), i.e. all the other rapidgrowing and slow-growing mycobacterial species. NTM are emerging pathogens causing infections in immunocompromised patients, in respiratory diseases and in iatrogenic infections. These bacteria are living in the environment (water and soils) and remain in the surface waters. They also infect insects, aquatic animals and protozoa. Outbreaks are due to contamination from a common reservoir and human to human transmission usually does not occur. Because mycobacteria harbor a thick lipid rich cell wall and many resistance genes in their genome, they are surviving even in water containing detergents or antibiotics. This can be one reason for their emergence in human infections. Detection of mycobacteria from water is not standardized and is difficult because it needs first to remove the other bacteria and cultivate mycobacteria in rich medium. Molecular detection can be used to circumvent this problem but have other drawbacks.