Investigation of Legionella Pneumophila serogroup 1 Population in Morocco by Monoclonal Antibody subtyping ,

Legionella Pneumophila is a common cause of hospital and community-acquired pneumonia, being transmitted by inhalation of aqueous aerosols. Most legionellosis outbreaks are linked to contaminated hot water systems and cooling towers. The aim of this preliminary study was to determine the population diversity of (n=40) environmental strains of L. pneumophila serogroup 1 recovered from the hot water distribution systems of nine establishments in four Moroccan towns during the period 2009–2011. Four subgroups were detected by monoclonal antibody technique. A total of 60% of isolates (n=24) had the virulence-associated epitope that is recognized by MAb 3/1 (32.5% of isolates belong to France/Allentown and 27.5% to Benidorm MAb subgroups). Forty percent (40%) of isolates, are not recognized by Mab 3/1 (27.5% of isolates belong to Olda and 12.5 % to Bellingham MAb subgroups). Our results showed the existence of various L. pneumophila serogroup 1 subgroups circulating in Morocco. The MAb patterns are thus a valuable adjunct to genotyping methods in defining subgroups inside a genotypic cluster of L. pneumophila serogroup 1.