Contamination of street food with multidrug-resistant Salmonella, in Ouagadougou, Burkina Faso.

BACKGROUND: Gastrointestinal infections are a global public health problem. In Burkina Faso, West Africa, exposure to Salmonella through the consumption of unhygienic street food represents a major risk of infection requiring detailed evaluation. METHODS: Between June 2017 and July 2018, we sampled 201 street food stalls, in 11 geographic sectors of Ouagadougou, Burkina Faso. We checked for Salmonella contamination in 201 sandwiches (one per seller), according to the ISO 6579:2002 standard. All Salmonella isolates were characterized by serotyping and antimicrobial susceptibility testing, and whole-genome sequencing was performed on a subset of isolates, to investigate their phylogenetic relationships and antimicrobial resistance determinants. RESULTS: The prevalence of Salmonella enterica was 17.9% (36/201) and the Salmonella isolates belonged to 16 different serotypes, the most frequent being Kentucky, Derby and Tennessee, with five isolates each. Six Salmonella isolates from serotypes Brancaster and Kentucky were multidrug-resistant (MDR). Whole-genome sequencing revealed that four of these MDR isolates belonged to the emergent S. enterica serotype Kentucky clone ST198-X1 and to an invasive lineage of S. enterica serotype Enteritidis (West African clade). CONCLUSION: This study reveals a high prevalence of Salmonella spp. in sandwiches sold in Ouagadougou. The presence of MDR Salmonella in food on sale detected in this study is also matter of concern.

[Microbial quality assessment of some street food widely consumed in Ouagadougou, Burkina Faso]. / Evaluation de la qualité microbiologique de quelques aliments de rue dans la ville de Ouagadougou au Burkina Faso.

The major part of the population of Ouagadougou, Burkina Faso, have their breakfast, dinner and lunch in street food shops. The characteristics of street food vendors are indicated. It appeared clearly that women play a major part (75%) in street food sale. Vendors have only a slight knowledge of food processing and of hygienic practices. There is a high proportion (about 50%) of people among them. This dietary habit has some negative aspects on the consumers' health. Ours studies clearly showed that hygienic practices during sales operations are not respected by all categories of vendors of food products. Also, it was observed that street food vendors sometimes sit close to the waste water drainage system and solid wastes. Sometimes, the food is not covered and it is manipulated by consumers in areas infested by flies and others insects. The water used to wash the materials is of poor quality. The second aspects of our studies showed that, in most cases, when the safety and hygienic practices were not respected, the food became a true microorganism culture medium under tropical climatic conditions. A table reports microbial analysis and contamination rates of some important street foods consumed in Ouagadougou. In general these results showed the failure of microbial quality of some food which is not preheated (milk product, fruit juice, vegetable, fruit) and in the case of food which is not reheated after a long time of exposition (dry meat and meat on sticks). The presence of Salmonella and Shigella species in some food represents a serious danger for consumers. These aspects were observed with most street food vendors. It probably makes street food the source of most diseases caused by bacteria and other microorganisms.