Presence of Clostridium perfringens in meat based preparations from publicfood services in San Jose, Costa Rica.

In Costa Rica there are a large number of public food services distributed alone the country, where a considerable number of people eat daily. Clostri dium perfringens is a bacteria associated with foodborne illness related, e specially, to meat products kept for long time at temperatures under 70 deg rees C. The aim of this study was to evaluate the public food services that use water baths for keeping food hot in order to establish the presence of C. perfringens in cooked bovine meat dishes and to evaluate the enterotoxi genic capacity of the strains isolated. 81 samples of cooked bovine meat plates coming from 27 public food services , located in the Central County of San Jose were analyzed. The methodology described by Labbe & Harmon for the isolation of C. perfringens was used in 10g of sample. Also, the enterotoxigenic capacity of the strains was evalu ated using the passive-reverse-latex-agglutination assay from Oxoid. From t he 27 public food services analyzed, eight (30%) were positive in the three samplings done, nine (33%) were positive in one or two occasions, and ten (37%) were negative all times. This implies that in 17 (63%) of the establi shments studied, the bacteria was isolated at least once. From the 81 prepa rations studied, 37 (46%) were positive for the bacteria. The temperatures at which food was kept varied from 56 to 82 degrees C, with an average of 6 8,7 degrees C. From the 37 strains identified as C. perfringens, 12 (32%) w ere positive for enterotoxin. In conclusion, the presence of C. perifringens in bovine meat dishes, maint ained in water baths, represents an important risk for public health, and t he temperature at which the preparation is kept is critical for the multipl ication of the bacteria.