A STUDY ON CERTAIN PHENOTYPIC AND GENOTYPIC CHARACTERS OF SALMONELLA TYPHI

Abstract

Salmonella enterica subspecies enterica serotype Typhi (S. Typhi) is newlinethe causative agent of typhoid fever that is still a major challenge for public newlinehealth in developing countries. The bacterium is transmitted by faeco-oral newlineroute, through contaminated water or food. Salmonella Typhi is highly newlineadapted to human host; the only reservoir is man. The diagnosis of typhoid newlinebecomes difficult as discriminating typhoid from other febrile disease is still newlineunclear. newline1.1 Epidemiology of Typhoid Fever newlineTyphoid fever is a major cause of morbidity and mortality among newlinehumans with an estimated global incidence of 21.6 million cases and 216510 newlinedeaths per year. In developing countries, its annual incidence ranges from newline12 to 622/100 000 persons (Gaind et al., 2006). newlineTyphoid fever is a major health problem in Southeast Asian countries newlineincluding Malaysia, Thailand, and Indonesia (Thong, 1995). In 2007, the newlineCommunicable Disease Centre (CDC) of Indonesia reported a prevalence of newline358-810 per 100,000 populations for typhoid fever with 64% occurring in 3 newlineto 19 year old (Moehario, 2009). In South Sulawesi, the case detection rate newlineincreased from 257 per 100,000 population in 1991 to 386 per 100,000 newlinepopulation in 2007 (Hatta, 2008). newlineIn Jakarta, typhoid fever was the second leading infectious disease newlineafter gastroenteritis and caused the highest mortality. The mortality rate newlinevaried from 3.1-10.4% among hospitalized patients with cases occurring newlinethroughout the year, peaking during the dry season (Moehario, 2009). newline1.2 Typhoid in India newlineEnteric fever, although not common in industrialized countries, newlineremains an important and persistent health problem in developing nations. newlineHospital based studies and outbreak reports from India indicate that enteric newlinefever is a major public health problem, with Salmonella enterica serovar newlineTyphi (S. Typhi) as the most common aetiological agent (Kanungo et al., newline2008). India, South and Central America and Africa are the regions where newlinethe disease is endemic, due to the rapid population increase, increasing newlineurbanization, rest