Mycobacterium avium complex, an emerging pathogen in Massachusetts

Abstract

We report a study of 1,953 patients whose laboratory records from 1972 through 1983 at the Massachusetts Mycobacteria Reference Laboratory indicated the isolation of Mycobacterium avium complex (MAC) organisms. At least one clinical specimen from each patient during this period exhibited the organism. The incidence of isolation of MAC has increased fivefold since 1972, with a doubling of the number of patients with positive MAC specimens from normally sterile sites occurring since 1980. A concomitant increase of more than fourfold in otbier nontuberculous mycobacteria has occurred. Most isolates came from high-density population centers. Communities whose drinking water comes from a distant rather than a local source were more likely to have patients with MAC.

Isolation Prevalence Of Pulmonary Nontuberculous Mycobacteria, Ontario 2008

“…All well-defined population-based studies that presented data on the frequency of pulmonary NTM isolation or disease over time have shown increases. [4][5][6][7][8][9] The numerous reports of increasing frequency are consistent with our results and suggest that pulmonary NTM infection is a growing problem. Increases in the frequency of pulmonary NTM throughout the world have not been adequately explained but there are several possible contributing factors.…”

“…All well-defined population-based studies of temporal trends of pulmonary NTM consistently report increases in frequency of 1.5-6-fold over 5-30 years. [4][5][6][7][8][9] The universally observed increases in frequency of pulmonary NTM infection makes this emerging infectious disease relevant to all pulmonary and infectious disease practitioners. The precise magnitude of the problem is not well understood for several reasons.…”

Heat susceptibility of aquatic mycobacteria

“…Human infections with NTM do not usually occur through person-to-person contact but rather occur through ingestion, inhalation, or inoculation of the organisms from environmental sources such as water (6,12,14,23). Mycobacteria that colonize public and domestic water supply systems have been associated with human NTM infections (6,(8)(9)(10)15). This association became particularly evident in nosocomial outbreaks.…”

Diagnosis and Prevention of Lung Diseases Associated with Microbial Bioaerosols

“…A Massachusetts study described an increased risk for M. avium complex infection in people whose water was supplied from a distant source. 50 A later survey of water from 34 sites in a hospital found positive cultures for M. avium at 14 sites (41%), the majority at hot water sites. 51 A nosocomial outbreak of pulmonary M. xenopi in 19 hospitalized patients was traced to a contaminated hospital hot water system.…”