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Determining the Best Immunization Strategy for Protecting African Children Against Invasive Salmonella Disease.

ABSTRACT: Background:The World Health Organization recently prequalified a typhoid conjugate vaccine (TCV), recommending its use in persons ?6 months to 45 years residing in typhoid fever (TF)-endemic areas. We now need to consider how TCVs can have the greatest impact in the most vulnerable populations. Methods:The Typhoid Fever Surveillance in Africa Program (TSAP) was a blood culture-based surveillance of febrile patients from defined populations presenting at healthcare facilities in 10 African countries. TF and invasive non-typhoidal Salmonella (iNTS) disease incidences were estimated for 0-10 year-olds in one-year age increments. Results:Salmonella Typhi and iNTS were the most frequently isolated pathogens; 135 and 94 cases were identified, respectively. Analysis from three countries was excluded (incomplete person-years of observation (PYO) data). Thirty-seven of 123 TF cases (30.1%) and 71/90 iNTS disease cases (78.9%) occurred in children aged <5 years. No TF and 8/90 iNTS infections (8.9%) were observed in infants aged <9 months. The TF incidences (/100 000 PYO) for children aged <1 year and 1 to <2 years were 5 and 39, respectively; the highest incidence was 304 per 100 000 PYO in 4 to <5 year-olds. The iNTS disease incidence in the defined age groups ranged between 81 and 233 per 100 000 PYO, highest in 1 to <2 year-olds. TF and iNTS disease incidences were higher in West Africa. Conclusions:High burden of TF detected in young children strengthens the need for TCV introduction. Given the concurrent iNTS disease burden, development of a trivalent vaccine against S. Typhi, S. Typhimurium, and S. Enteritidis may be timely in this region.

SUBMITTER: Jeon HJ

PROVIDER: S-EPMC6260167 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Determining the Best Immunization Strategy for Protecting African Children Against Invasive Salmonella Disease.

Jeon Hyon Jin HJ Pak Gi Deok GD Im Justin J Owusu-Dabo Ellis E Adu-Sarkodie Yaw Y Gassama Sow Amy A Bassiahi Soura Abdramane A Gasmelseed Nagla N Keddy Karen H KH Bjerregaard-Andersen Morten M Konings Frank F Aseffa Abraham A Crump John A JA Chon Yun Y Breiman Robert F RF Park Se Eun SE Cruz Espinoza Ligia Maria LM Seo Hye Jin HJ May Jürgen J Meyer Christian G CG Andrews Jason R JR Panzner Ursula U von Kalckreuth Vera V Wierzba Thomas F TF Rakotozandrindrainy Raphaël R Dougan Gordon G Levine Myron M MM Hombach Joachim J Kim Jerome H JH Clemens John D JD Baker Stephen S Marks Florian F

Clinical infectious diseases : an official publication of the Infectious Diseases Society of America 20181101 12

<h4>Background</h4>The World Health Organization recently prequalified a typhoid conjugate vaccine (TCV), recommending its use in persons ≥6 months to 45 years residing in typhoid fever (TF)-endemic areas. We now need to consider how TCVs can have the greatest impact in the most vulnerable populations.<h4>Methods</h4>The Typhoid Fever Surveillance in Africa Program (TSAP) was a blood culture-based surveillance of febrile patients from defined populations presenting at healthcare facilities in 10 ...[more]

PMID: 29746615

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Determining the Best Immunization Strategy for Protecting African Children Against Invasive Salmonella Disease.

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Determining the Best Immunization Strategy for Protecting African Children Against Invasive Salmonella Disease.

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