Prevalence of anti-Salmonella enterica serovar Typhi antibodies in individuals from Culiacan, Sinaloa, Mexico

Abstract

To estimate the prevalence of specific antibodies against Salmonella enterica serovar Typhi (S. Typhi) in individuals from Culiacan, Sinaloa, Mexico. A cross-sectional study was conducted at the University Clinical Analysis Laboratory "MC Héctor Cuén Ojeda" in Culiacán, Sinaloa, Mexico, during the period 2009-2010. In this study, 366 individuals attended the laboratory to obtain a medical certificate. The serum of each individual was obtained and analyzed by Widal agglutination. Positive samples to Widal (dilution 1:160), were tested by Western blotting using an antigenic extract of S. Typhi (AEST). Of 366 sera analyzed, 10.11% (n=37) were Widal-positive. The Western blot developed using these sera revealed four prominent antigens: a 25 kDa protein was recognized by 35 sera (94.6%), 24 kDa and 30 kDa proteins were reactive to the same number of sera, with 34 (91.9%), and 33 (89.2%) recognized a 60 kDa protein. In conclusion, the anti-S. Typhi seroprevalence obtained was 10.11%, and four proteins derived from AEST were identified with high immunoreactivity (>89%), the 25 kDa antigen was the immunodominant. It is necessary to continue studying these detected antigens and increase our knowledge about the estimation of seroprevalence of S. Typhi, whose infection keeps Sinaloa within the 5 states with the highest incidence of Typhoid Fever in Mexico.