Seroprevalence of Typhoid Fever among Subjects with Acute Febrile Manifestations at Tertiary Care Center, Addis Ababa, Ethiopia

Background: Typhoid fever is a life-threatening systemic disease characterized by stepwise rise of fever (38-41C) and frequent abdominal manifestations. It continued to be a major endemic disease in developing countries where there are unsanitary practices. The reports of global burden of typhoid fever suggested that up to 16 to 22 million cases and 200 000 to 600, 000 deaths occur each year. Over past decades varying trend observed in developing countries, which reported of having an average incidence of 540 per 100, 000 populations. In Ethiopia, the definite diagnosis of typhoid fever by isolating the organisms is not normally done because of lack of bacteriological facilities and longer time required. However, the sensitive rapid slide agglutination tests alone, mostly without tube dilution method, routinely performed to detect presence of antibody production against typhoid fever. Here, we determined the seroprevalence of Salmonella Typhi from patients suspected of typhoid fever at the International Clinical Laboratories, Addis Ababa, Ethiopia. Result: Over five years, a total of 5, 029 patients with suspicion of typhoid fever were serologically diagnosed in the International Clinical Laboratories, Addis Ababa, Ethiopia. Of those patients, smaller numbers (43 %) were females with 17 % Widal positive and greater numbers (57 %) were male with 12 % Widal positive. The age of patients distributed from less than a year to eight seven years and mean age was located at 33.3914.72 years [95 % CI]. Approximately 22 % of patients had significant titer equal to 1 in 20 or more for H and/or O agglutinins corresponding antibody presence in serum. Of widal tests, 8.26 % had significantly reactive antibody against H and O antigens whereas 6.7 % and 5 % were significantly reactive for only H and O antigens, respectively. The significant titer level indicative of typhoid diagnosis was equal to 1 in 80l or more in both H and O agglutinins. Conclusion: Widal slide test is non-specific test that need additional confirmatory tube tests and bacteriological isolation of Salmonella Typhi. Hence, seroprevalence report may overstate or understate estimate of typhoid fever.