title: The burden of invasive bacterial infections in Pemba, Zanzibar.
abstract: BACKGROUND
  We conducted a surveillance study to determine the leading causes of bloodstream infection in febrile patients seeking treatment at three district hospitals in Pemba Island, Zanzibar, Tanzania, an area with low malaria transmission.
  
  
  METHODS
  All patients above two months of age presenting to hospital with fever were screened, and blood was collected for microbiologic culture and malaria testing. Bacterial sepsis and malaria crude incidence rates were calculated for a one-year period and were adjusted for study participation and diagnostic sensitivity of blood culture.
  
  
  RESULTS
  Blood culture was performed on 2,209 patients. Among them, 166 (8%) samples yielded bacterial growth; 87 (4%) were considered as likely contaminants; and 79 (4%) as pathogenic bacteria. The most frequent pathogenic bacteria isolated were Salmonella Typhi (n = 46; 58%), followed by Streptococcus pneumoniae (n = 12; 15%). The crude bacteremia rate was 6/100,000 but when adjusted for potentially missed cases the rate may be as high as 163/100,000. Crude and adjusted rates for S. Typhi infections and malaria were 4 and 110/100,000 and 4 and 47/100,000, respectively. Twenty three (51%), 22 (49%) and 22 (49%) of the S. Typhi isolates were found to be resistant toward ampicillin, chloramphenicol and cotrimoxazole, respectively. Multidrug resistance (MDR) against the three antimicrobials was detected in 42% of the isolates.
  
  
  CONCLUSIONS
  In the presence of very low malaria incidence we found high rates of S. Typhi and S. pneumoniae infections on Pemba Island, Zanzibar. Preventive measures such as vaccination could reduce the febrile disease burden.
authors.affiliation: International Vaccine Institute, Seoul, Republic of Korea. k.leythriemer@gmail.com
authors.forename: Kamala
authors.initials: K
authors.lastname: Thriemer
authors.forename: Benedikt
authors.initials: B
authors.lastname: Ley
authors.forename: Shaali
authors.initials: S
authors.lastname: Ame
authors.forename: Lorenz
authors.initials: L
authors.lastname: von Seidlein
authors.forename: Gi Deok
authors.initials: GD
authors.lastname: Pak
authors.forename: Na Yoon
authors.initials: NY
authors.lastname: Chang
authors.forename: Ramadhan
authors.initials: R
authors.lastname: Hashim
authors.forename: Wolfgang Hellmut
authors.initials: WH
authors.lastname: Schmied
authors.forename: Clara Jana-Lui
authors.initials: CJ
authors.lastname: Busch
authors.forename: Shanette
authors.initials: S
authors.lastname: Nixon
authors.forename: Anne
authors.initials: A
authors.lastname: Morrissey
authors.forename: Mahesh K
authors.initials: MK
authors.lastname: Puri
authors.forename: Mohammad
authors.initials: M
authors.lastname: Ali
authors.forename: R Leon
authors.initials: RL
authors.lastname: Ochiai
authors.forename: Thomas
authors.initials: T
authors.lastname: Wierzba
authors.forename: Mohammad S
authors.initials: MS
authors.lastname: Jiddawi
authors.forename: John D
authors.initials: JD
authors.lastname: Clemens
authors.forename: Said M
authors.initials: SM
authors.lastname: Ali
authors.forename: Jaqueline L
authors.initials: JL
authors.lastname: Deen
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D016470:Bacteremia / Q000150:complications / Q000453:epidemiology* / Q000382:microbiology; D001419:Bacteria / Q000187:drug effects; D001424:Bacterial Infections / Q000150:complications / Q000453:epidemiology* / Q000382:microbiology*; D002648:Child; D002675:Child, Preschool; D005843:Geography; D006761:Hospitals / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D008288:Malaria / Q000150:complications / Q000453:epidemiology; D008826:Microbial Sensitivity Tests; D013636:Tanzania / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents