title: The burden and characteristics of enteric fever at a healthcare facility in a densely populated area of Kathmandu.
abstract: Enteric fever, caused by Salmonella enterica serovars Typhi and Paratyphi A (S. Typhi and S. Paratyphi A) remains a major public health problem in many settings. The disease is limited to locations with poor sanitation which facilitates the transmission of the infecting organisms. Efficacious and inexpensive vaccines are available for S. Typhi, yet are not commonly deployed to control the disease. Lack of vaccination is due partly to uncertainty of the disease burden arising from a paucity of epidemiological information in key locations. We have collected and analyzed data from 3,898 cases of blood culture-confirmed enteric fever from Patan Hospital in Lalitpur Sub-Metropolitan City (LSMC), between June 2005 and May 2009. Demographic data was available for a subset of these patients (n = 527) that were resident in LSMC and who were enrolled in trials. We show a considerable burden of enteric fever caused by S. Typhi (2,672; 68.5%) and S. Paratyphi A (1,226; 31.5%) at this Hospital over a four year period, which correlate with seasonal fluctuations in rainfall. We found that local population density was not related to incidence and we identified a focus of infections in the east of LSMC. With data from patients resident in LSMC we found that the median age of those with S. Typhi (16 years) was significantly less than S. Paratyphi A (20 years) and that males aged 15 to 25 were disproportionately infected. Our findings provide a snapshot into the epidemiological patterns of enteric fever in Kathmandu. The uneven distribution of enteric fever patients within the population suggests local variation in risk factors, such as contaminated drinking water. These findings are important for initiating a vaccination scheme and improvements in sanitation. We suggest any such intervention should be implemented throughout the LSMC area.
authors.affiliation: Oxford University Clinical Research Unit, Patan Academy of Health Sciences, Lagankhel, Kathmandu, Nepal.
authors.forename: Abhilasha
authors.initials: A
authors.lastname: Karkey
authors.forename: Amit
authors.initials: A
authors.lastname: Arjyal
authors.forename: Katherine L
authors.initials: KL
authors.lastname: Anders
authors.forename: Maciej F
authors.initials: MF
authors.lastname: Boni
authors.forename: Sabina
authors.initials: S
authors.lastname: Dongol
authors.forename: Samir
authors.initials: S
authors.lastname: Koirala
authors.forename: Phan Vu Tra
authors.initials: PV
authors.lastname: My
authors.forename: Tran Vu Thieu
authors.initials: TV
authors.lastname: Nga
authors.forename: Archie C A
authors.initials: AC
authors.lastname: Clements
authors.forename: Kathryn E
authors.initials: KE
authors.lastname: Holt
authors.forename: Pham Thanh
authors.initials: PT
authors.lastname: Duy
authors.forename: Jeremy N
authors.initials: JN
authors.lastname: Day
authors.forename: James I
authors.initials: JI
authors.lastname: Campbell
authors.forename: Gordon
authors.initials: G
authors.lastname: Dougan
authors.forename: Christiane
authors.initials: C
authors.lastname: Dolecek
authors.forename: Jeremy
authors.initials: J
authors.lastname: Farrar
authors.forename: Buddha
authors.initials: B
authors.lastname: Basnyat
authors.forename: Stephen
authors.initials: S
authors.lastname: Baker
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology; D005260:Female; D005843:Geography; D006268:Health Facilities; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009390:Nepal / Q000453:epidemiology; D010284:Paratyphoid Fever / Q000453:epidemiology* / Q000382:microbiology; D011156:Population Density; D015995:Prevalence; D012482:Salmonella paratyphi A / Q000302:isolation & purification*; D012485:Salmonella typhi / Q000302:isolation & purification*; D012621:Seasons; D013045:Species Specificity; D014435:Typhoid Fever / Q000453:epidemiology* / Q000382:microbiology; D055815:Young Adult