Mycobacterium abscessus, a rapidly growing acid-fast bacterium naturally found in water, soil, and dust, is an opportunistic pathogen that causes rare infections of the skin and subcutaneous tissues. Outbreaks of skin infections related to recreational water exposure were identified in Canada in 2003, and in Italy 2009–2011, but no previous outbreaks associated with recreational water in the U.S. had been reported. In Idaho, February –May 2013, M. abscessus skin infections were diagnosed in 11 children.
Clinical evaluation of children, mycobacterial culture and identification, and epidemiologic and environmental investigations were performed.
Affected children were aged 2–6 years; 9 (82%) were female. All were otherwise healthy with no diagnosed immunocompromising conditions. Most children presented with erythematous nodular lesions on their hands or feet. In some cases, initial symptoms were attributed to viral hand, foot, and mouth disease. Illness onsets occurred January – May 2013. One case was confirmed as M. abscessus group not chelonae by bacterial RNA polymerase β subunit (rpoB) gene sequencing, 2 were confirmed as M. abscessus/chelonae complex by 16S rDNA sequence analysis, and in 2 cases, acid-fast bacilli were detected in fixed skin biopsy or smear of exudate; 6 additional clinically-compatible cases shared epidemiologic risk factors. Epidemiologic investigation determined that the sole common exposure among cases was playing in a fitness facility’s wading pool December 2012 – April 2013. Environmental investigation found a worn rubber mat on the bottom of the pool at the slide exit and worn polyurethane decking suspected to have allowed colonization by M. abscessus. Swabs of the fountain strainer and slide ladder cultured positive for M. abscessus/chelonae with pulsed-field gel electrophoresis patterns related, but not identical to those of clinical isolates. Mycobacterium spp.were isolated from the pool water. The pool operator hyperchlorinated, drained, scrubbed, and disinfected the pool. The worn rubber mat was replaced. No associated cases were reported after environmental remediation.
An outbreak of M. abscessus skin infections among children was associated with a wading pool and controlled by environmental remediation. This was the first such reported outbreak in the U.S.
K. Carter, None
S. Correll, None
A. Bruesch, None
T. Rand, None