FREQUENCY OF SALMONELLA ANTIBODIES AMONG FEBRILE PATIENTS WITH SUSPECTED ENTERIC FEVER

Abstract

Iraq is an endemic area with Salmonella, hence most population are with highSalmonella-specific antibody titer due to their continuous exposure to this bacterium.This study was conducted from June 2010 to May 2011 on outpatients in publichospitals in Baghdad city to evaluate Widal test as a diagnostic kit for enteric fever usingserum of 200 febrile patients at ages from 9 to 66 of both sexes. The overall seroprevalenceof anti-O for Salmonella typhi was 56% (35% for females and 21% for males). Out of thisrate, 3% were with only anti-O for S typhi, 9% were with anti-O and anti-H for S typhi,27% were with anti-O (with or without anti-H) for S typhi plus anti-H for S paratyphi A orB, and 17 % were with anti-O (with or without anti-H) for S typhi plus anti-O (with orwithout anti-H) for S paratyphi A or B. The frequency of anti-O for S paratyphi was 1% forgroup A only, 24% for group B only and 1% for both A + B. For the old infections thatwere presented with only anti-H antibodies, the seroprevalence rate was 3% for S typhionly, and from 1-4% for other types of Salmonella or mixed infections. Concerning theseasonal variations, the highest rate of seroprevalence (40%) was in spring season and thelowest one (10%) was in winter season. In conclusion, using one sample Widal serologywith a cut-off positive value of 160 and more is a valuable test for the diagnosis of entericfever in highly endemic areas as the city of Baghdad. Worth to mention that most caseswith confirmed enteric cases results (using one sample Widal serology) were of mixedorigin of infection with S typhi and S paratyphi serotypes.