Water-borne household infections due to Mycobacterium xenopi.

Of 21 M. xenopi excretors recorded in Prague in 1990, 13 suffered from a serious pulmonary disease and the organisms were detected repeatedly in all of them. In 11 flats of these excretors water samples were collected from faucets and showers and M. xenopi was detected in five of them, as well as in five neighbouring flats. In flats of six remaining excretors and 12 adjoining flats, M. xenopi was not found. However, in 14 of 28 examined flats, the clinically insignificant M. gordonae was isolated. Water samples from three water-works, six regional water reservoirs and 10 street hydrants did not harbour mycobacteria. In the authors' view M. xenopi originating from infected drinking water outlets may cause infections in exposed household dwellers.