Keddy, Karen H.Sooka, ArvindaIsmail, H.Smith, Anthony MariusWeber, Ingrid BrigitteLetsoalo, M.E.Harris, Bernice Nerine2011-06-132011-06-132010-09Keddy, KH, Sooka, A, Ismail, H, Smith, AM, Weber, I, Letsoalo, ME & Harris, BN 2010, 'Molecular epidemiological investigation of a typhoid fever outbreak in South Africa, 2005 : the relationship to a previuos epidemic in 1993', Epidemiology and Infection, pp. 1-7. [http://journals.cambridge.org/action/displayJournal?jid=HYG]0950-2688 (print)1469-4409 (online)10.1017/S0950268810002207http://hdl.handle.net/2263/16811In 2005, over 600 clinically diagnosed typhoid fever cases occurred in South Africa, where an outbreak had been previously described in 1993. Case-control and molecular investigations, including Salmonella enterica serovar Typhi (S. Typhi) isolates from that area from 1993, 2005 and later, were undertaken. Controls were significantly older than cases (P=0.003), possibly due to immunity from previous infection, and a significantly larger proportion had attended a gathering (P=0.035). Exposure to commercial food outlets and person-to-person transmission was not significant. Pulsed-field gel electrophoresis and multi-locus tandem repeat analysis revealed common clusters of S. Typhi strains identified in 1993 and 2005 as well as in 2007 and 2009. This outbreak probably occurred in a non-immune population due to faecally contaminated water. S. Typhi strains appeared to be related to strains from 1993; failure to address unsafe water may lead to further outbreaks in the area if the current population immunity wanes or is lost.en© Cambridge University Press 2010.EpidemicMultiple-locus variable-number tandem repeat analysis (MLVA)Pulsed-field gel electrophoresis (PFGE)South AfricaTyphoid feverTyphoid fever -- South AfricaMicrobial contamination -- South AfricaWater quality -- South AfricaArticle