The prevalence of Salmonella typhi and paratyphi A, B and C were investigated in blood samples of patients attending General Hospital and two other clinics in Biu Local Government area of Borno State, Northeastern Nigeria. A total of 204 blood samples, from 90 (44.1%) males and 114 (55.9%) females were collected from patients, within a two month period. Widal test was used to detect the antibody titers in sera, obtained by centrifugation at 3000rpm for 5 minutes. About (39) 43.3% males and (45) 39.5% females were positive. Higher numbers of positive cases were recorded for patients within 13-24 (45.9%) and 25-46 (42.9%) age ranges, but no case was reported for patients ≥ 68 years of age (n=2). Based on occupation, students/pupils have the highest (68.2%) antibody titers among different groups. More positive samples were detected in unmarried patients (47.5%), compared to married ones (36.6%), even though, there is no statistical significance (P > 0.05). About 27% of the samples showed the presence of group O antigens. This was followed by Salmonella paratyphi B (25%), Salmonella typhi (20.6%) and Salmonella paratyphi C (13.7%). For the H antigens however, they were in the order: Salmonella paratyphi B (25%) > Salmonella paratyphi C (19.6%) > Salmonella paratyphi A (18.6%) ≥ Salmonella typhi (18.6%).
