Population-based incidence, seasonality and serotype distribution of invasive salmonellosis among children in Nanoro, rural Burkina Faso

Abstract

BackgroundBloodstream infections (BSI) caused by Salmonella Typhi and invasive non-Typhoidal Salmonella (iNTS) frequently affect children living in rural sub-Saharan Africa but data about incidence and serotype distribution are rare.ObjectiveThe present study assessed the population-based incidence of Salmonella BSI and severe malaria in a Health and Demographic Surveillance System in a rural area with seasonal malaria transmission in Nanoro, Burkina Faso.MethodsChildren between 2 months—15 years old with severe febrile illness were enrolled during a one-year surveillance period (May 2013—May 2014). Thick blood films and blood cultures were sampled and processed upon admission. Population-based incidences were corrected for non-referral, health seeking behavior, non-inclusion and blood culture sensitivity. Adjusted incidence rates were expressed per 100,000 person-years of observations (PYO).ResultsAmong children < 5 years old, incidence rates for iNTS, Salmonella Typhi and severe malaria per 100,000 PYO were 4,138 (95% Confidence Interval (CI): 3,740–4,572), 224 (95% CI: 138–340) and 2,866 (95% CI: 2,538–3,233) respectively. Among those aged 5–15 years, corresponding incidence rates were 25 (95% CI: 8–60), 273 (95% CI: 203–355) and 135 (95% CI: 87–195) respectively. Most iNTS occurred during the peak of the rainy season and in parallel with the increase of Plasmodium falciparum malaria; for Salmonella Typhi no clear seasonal pattern was observed. Salmonella Typhi and iNTS accounted for 13.3% and 55.8% of all 118 BSI episodes; 71.6% of iNTS (48/67) isolates were Salmonella enterica serovar Typhimurium and 25.4% (17/67) Salmonella enterica serovar Enteritidis; there was no apparent geographical clustering.ConclusionThe present findings from rural West-Africa confirm high incidences of Salmonella Typhi and iNTS, the latter with a seasonal and Plasmodium falciparum-related pattern. It urges prioritization of the development and implementation of Salmonella Typhi as well as iNTS vaccines in this setting.

Non-typhoidal Salmonella bloodstream infections in Kisantu, DR Congo: Emergence of O5-negative Salmonella Typhimurium and extensive drug resistance

“…Similar to the results presented in this study, the Typhimurium-to-Enteritidis ratio varied between 1:1 to 1:8 between countries [44]. Variations in serotype distribution over time or between centers have been recently described in Malawi, Burkina Faso and Mali [45][46][47].…”

Complications and mortality of typhoid fever: A global systematic review and meta-analysis

“…Among 13,303 confirmed typhoid cases from studies reporting mortality, 250 died, for a CFR of 1.9% ( Table 3) Sixty-seven (84.8%) of 79 non-surgical study sites were hospital-based, and 12 (15.2%) were population or community-based studies. 37,38,60,73,84,90,96,118 Ten (83.3%) of 12 non-hospital study sites were located in Asia and two (16.7%) in Africa; one each in Kenya 37 and Burkina Faso. 60 No deaths were reported among 866 confirmed typhoid cases in the 12 non-hospital sites compared to 250 (2.0%) of 12,437 hospital-based confirmed cases (Χ 2 =16.7; p<0.01).…”

A Systematic Review and Meta-analysis of the Prevalence of Community-Onset Bloodstream Infections among Hospitalized Patients in Africa and Asia

“…Fifteen studies (34.1%) used blood film microscopy to test 10,451 participants for malaria and identified parasitemia in 4,301 (41.2%) (31,32,35,36,38,40,41,43,45,46,(60)(61)(62)(63)(64)(65). Eight studies reported malaria and BSI coinfection (31,32,43,45,(61)(62)(63)65 (62,65).…”

“…Fifteen studies (34.1%) used blood film microscopy to test 10,451 participants for malaria and identified parasitemia in 4,301 (41.2%) (31,32,35,36,38,40,41,43,45,46,(60)(61)(62)(63)(64)(65). Eight studies reported malaria and BSI coinfection (31,32,43,45,(61)(62)(63)65 (62,65). Twelve (27.3%) studies with 8,109 participants tested patients for HIV using either serological or nucleic acid amplification methods and described BSI coinfection (32,33,35,36,40,41,48,61,62,65,67,69).…”