RMU

Background: Shigella flexneri is the most frequent bacterial agent in infants under 5 years old with bloody diarrhea. Shigellosis is an infectious disease successfully treated with antibiotics. Empirical choice of the adequate antibiotic is difficult due to Shigella-resistant antibiotics.

This situation promoted the interest to develop vaccines able to control the disease. Since many vaccines tend to promote specific serotype immune response, it is important to categorise prevalent serotypes in the population study. The aim of the study was to categorise 50 isolated Shigella flexneri strains in infants with bloody diarrhea, collected in four etiologic surveys of gastroenteritis.

Methods: serotypification, lipopolysaccharide patterns, plasmid profile and sensitivity to different antibiotics were carried out in each strain.

Results: prevalent serotypes were 2a, 3c, 4, 6, y 1. Ten different antibiotypes were identified. In serotype 2a, 3 plasmidic patterns were found; 5 was the most frequent, followed by 6 and 7. Analyse of present antibiotypes showed a trend to an enlargement of the resistance range.

Conclusions: according to results, immunogen should include specific ?O? determinants for 2a, 1, 3c, 4, 6 and Shigella sonnei serotypes.