Abstract
Background: Preliminary investigation at Pediatric ward of Indira Gandhi Medical College revealed admission of a cluster of typhoid cases who were residents of one particular street in a nearby locality. Objectives: This study was undertaken to estimate the magnitude of the outbreak, identify the source of infection, and, thereby, institute control measures. MaterialsandMethods: Aninvestigationteam including10MBBS studentscarried outasanitary survey, house-to-house survey, data collection using epidemiological case sheets, and spot mapping. Typhoid diagnosis was conï¬rmed as per the IDSP guidelines, i.e., either a blood culture growth positive for Salmonella typhi or a fourfold rise in antibody titer. An age- and gender-matched case–control study was conducted to ï¬nd the association of occurrence of typhoid with various possiblesourcesofinfection.Watersampleswerecollectedfromtheaffectedhouseholdsandpublictapsforinvestigation. Results: Rapid survey of all the 6 streets of Thilaspet covered 1106 people living in 283 households. All nine conï¬rmed cases were residents of one particular street. The attack rate calculated was 3.4% in this street. A signiï¬cant association of occurrenceoftyphoidwasfoundonlywithconsumptionofrawdrinkingwater(OR=12.6,P=0.01).Watersamplesonlyfrom the affected street tested positive for the presence of coliforms. The sanitary survey documented water pipeline breakage at thejunctionofthisstreet.Furtherspreadofdiseasewasstoppedbyadvocatingdrinkingofboiledwaterandrepairofpipeline. Conclusion: Strengthening of disease surveillance for early identiï¬cation of localized outbreaks and instituting control measures can effectively control disease spread.