Incidence of invasive salmonella disease in sub-Saharan Africa: a multicentre population-based surveillance study

• Type of Material: Article
• Authors: Florian Marks, Seoul National University; Vera von Kalckreuth, Seoul National University; Peter Aaby, Bandim Health Project; Yaw Adu-Sarkodie, Kwame Nkrumah University of Science and Technology; Muna Ahmed El Tayeb, University of Gezira; Mohammad Ali, Johns Hopkins University; Abraham Aseffa, Armauer Hansen Research Institute; Stephen Baker, Oxford University; Holly M. Biggs, Kilimanjaro Christian Medical Centre; Morten Bjerregaard-Andersen, Bandim Health Project; Robert Breiman, Emory University; James I. Campbell, Oxford University; Leonard Cosmas, Centers for Disease Control and Prevention; John A. Crump, Kilimanjaro Christian Medical Centre; Ligia Maria Cruz Espinoza, Seoul National University; Jessica Fung Deerin, Seoul National University; Denise Myriam Dekker, Bernhard Nocht Institute for Tropical Medicine; Barry S. Fields, Centers for Disease Control and Prevention; Nagla Gasmelseed, University of Gezira; Julian T. Hertz, Kilimanjaro Christian Medical Centre; Nguyen Van Minh Hoang, Oxford University; Justin Im, Seoul National University; Anna Jaeger, Bernhard Nocht Institute for Tropical Medicine; Hyon Jin Jeon, Seoul National University; Leon Parfait Kabore, Schiphra Hospital; Karen H. Keddy, National Institute for Communicable Diseases, South Africa; Frank Konings, Seoul National University; Ralf Krumkamp, Bernhard Nocht Institute for Tropical Medicine; Benedikt Ley, Seoul National University; Sandra Valborg Løfberg, Bandim Health Project; Jürgen May, Bernhard Nocht Institute for Tropical Medicine; Christian G. Meyer, University of Tübingen; Eric D. Mintz, National Center for Emerging and Zoonotic Infectious Diseases; Joel M. Montgomery, Centers for Disease Control and Prevention; Aissatou Ahmet Niang, Institute Pasteur de Dakar; Chelsea Nichols, Seoul National University; Beatrice Olack, Kenya Medical Research Institute; Gi Deok Pak, Seoul National University; Ursula Panzner, Seoul National University; Jin Kyung Park, Seoul National University; Se Eun Park, Seoul National University; Henintsoa Rabezanahary, University of Antananarivo; Raphaël Rakotozandrindrainy, University of Antananarivo; Tiana Mirana Raminosoa, University of Antananarivo; Tsiriniaina Jean Luco Razafindrabe, University of Antananarivo; Emmanuel Sampo, Schiphra Hospital; Heidi Schütt-Gerowitt, Seoul National University; Amy Gassama Sow, Institute Pasteur de Dakar; Nimako Sarpong, Kwame Nkrumah University of Science and Technology; Hye Jin Seo, Seoul National University; Arvinda Sooka, National Institute for Communicable Diseases, South Africa; Abdramane Bassiahi Soura, University of Ouagadougou; Adama Tall, Institute Pasteur de Dakar; Mekonnen Teferi, Armauer Hansen Research Institute; Kamala Thriemer, Seoul National University; Michelle R. Warren, Seoul National University; Biruk Yeshitela, Armauer Hansen Research Institute; John D. Clemens, Seoul National University; Thomas F. Wierzba, Seoul National University
• Language: English
• Date: 2017-03-01
• Publisher: Elsevier
• Publication Version: Final Published Version
• Copyright Statement: © 2017 The Author(s).
• License: Creative Commons Attribution 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1016/S2214-109X(17)30022-0
• Title of Journal or Parent Work: Lancet Global Health
• ISSN: 2214-109X
• Volume: 5
• Issue: 3
• Start Page: e310
• End Page: e323
• Grant/Funding Information: International Vaccine Institute acknowledges its donors, including the South Korea and the Swedish International Development Cooperation Agency (Sida).; This study was supported by the Bill & Melinda Gates Foundation (OPPGH5231).; Research infrastructure at the Moshi site was supported by the US National Institutes of Health (R01TW009237; U01 AI062563; R24 TW007988; D43 PA-03–018; U01 AI069484; U01 AI067854; P30 AI064518), and by the UK Biotechnology and Biological Sciences Research Council (BB/J010367).; SB is a Sir Henry Dale Fellow, jointly funded by the Wellcome Trust and the Royal Society (100087/Z/12/Z).
• Research Categories: Health Sciences, Epidemiology; Health Sciences, Pathology

Abstract

Background: Available incidence data for invasive salmonella disease in sub-Saharan Africa are scarce. Standardised, multicountry data are required to better understand the nature and burden of disease in Africa. We aimed to measure the adjusted incidence estimates of typhoid fever and invasive non-typhoidal salmonella (iNTS) disease in sub-Saharan Africa, and the antimicrobial susceptibility profiles of the causative agents. Methods: We established a systematic, standardised surveillance of blood culture-based febrile illness in 13 African sentinel sites with previous reports of typhoid fever: Burkina Faso (two sites), Ethiopia, Ghana, Guinea-Bissau, Kenya, Madagascar (two sites), Senegal, South Africa, Sudan, and Tanzania (two sites). We used census data and health-care records to define study catchment areas and populations. Eligible participants were either inpatients or outpatients who resided within the catchment area and presented with tympanic (≥38·0°C) or axillary temperature (≥37·5°C). Inpatients with a reported history of fever for 72 h or longer were excluded. We also implemented a health-care utilisation survey in a sample of households randomly selected from each study area to investigate health-seeking behaviour in cases of self-reported fever lasting less than 3 days. Typhoid fever and iNTS disease incidences were corrected for health-care-seeking behaviour and recruitment. Findings: Between March 1, 2010, and Jan 31, 2014, 135 Salmonella enterica serotype Typhi (S Typhi) and 94 iNTS isolates were cultured from the blood of 13 431 febrile patients. Salmonella spp accounted for 33% or more of all bacterial pathogens at nine sites. The adjusted incidence rate (AIR) of S Typhi per 100 000 person-years of observation ranged from 0 (95% CI 0–0) in Sudan to 383 (274–535) at one site in Burkina Faso; the AIR of iNTS ranged from 0 in Sudan, Ethiopia, Madagascar (Isotry site), and South Africa to 237 (178–316) at the second site in Burkina Faso. The AIR of iNTS and typhoid fever in individuals younger than 15 years old was typically higher than in those aged 15 years or older. Multidrug-resistant S Typhi was isolated in Ghana, Kenya, and Tanzania (both sites combined), and multidrug-resistant iNTS was isolated in Burkina Faso (both sites combined), Ghana, Kenya, and Guinea-Bissau. Interpretation: Typhoid fever and iNTS disease are major causes of invasive bacterial febrile illness in the sampled locations, most commonly affecting children in both low and high population density settings. The development of iNTS vaccines and the introduction of S Typhi conjugate vaccines should be considered for high-incidence settings, such as those identified in this study.