Traditional milk transformation schemes in Côte d'Ivoire and their impact on the prevalence of Streptococcus bovis complex bacteria in dairy products

The Streptococcus bovis/Streptococcus equinus complex (SBSEC) and possibly Streptococcus infantarius subsp. infantarius (Sii) are associated with human and animal diseases. Sii predominate in spontaneously fermented milk products with unknown public health effects. Sii/SBSEC prevalence data from West Africa in correlation with milk transformation practices are limited. Northern Côte d'Ivoire served as study area due to its importance in milk production and consumption and to link a wider Sudano-Sahelian pastoral zone of cross-border trade. We aimed to describe the cow milk value chain and determine Sii/SBSEC prevalence with a cross-sectional study. Dairy production practices were described as non-compliant with basic hygiene standards. The system is influenced by secular sociocultural practices and environmental conditions affecting product properties. Phenotypic and molecular analyses identified SBSEC in 27/43 (62.8%) fermented and 26/67 (38.8%) unfermented milk samples. Stratified by collection stage, fermented milk at producer and vendor levels featured highest SBSEC prevalence of 71.4% and 63.6%, respectively. Sii with 62.8% and 38.8% as well as Streptococcus gallolyticus subsp. macedonicus with 7.0% and 7.5% were the predominant SBSEC species identified among fermented and unfermented milk samples, respectively. The population structure of Sii/SBSEC isolates seems to reflect evolving novel dairy-adapted, non-adapted and potentially pathogenic lineages. Northern Côte d'Ivoire was confirmed as area with high Sii presence in dairy products. The observed production practices and the high diversity of Sii/SBSEC supports in-depth investigations on Sii ecology niche, product safety and related technology in the dairy value chain potentially affecting large population groups across sub-Saharan Africa

Risk factors for the carriage of Streptococcus infantarius subspecies infantarius isolated from African fermented dairy products

Streptococcus infantarius subsp. infantarius (Sii) has been identified as predominant lactic acid bacteria in spontaneously fermented dairy products (FDPs) in sub-Saharan Africa including Côte d'Ivoire. However, Sii belongs to the Streptococcus bovis/Streptococcus equinus complex (SBSEC). Most SBSEC members are assumed to be involved as opportunistic pathogens in serious diseases in both humans and animals. A population-based cross-sectional survey, including 385 participants was conducted in Korhogo, northern Côte d'Ivoire, to identify risk factors for Sii fecal carriage, including consumption of local FDPs. A structured questionnaire was used to gather participant's socio-demographic and economic characteristics, their relation to livestock and dietary habits. In addition, fresh stool and milk samples were collected. The identification of Sii was done using a SBSEC-specific PCR assay targeting 16S rRNA and groEL genes. The overall prevalence of SBSEC and Sii carriage was 23.2% (confidence interval CI 95% = 18.9-27.5) and 12.0% (CI 95% = 8.4-15.5) for stool, respectively. Prevalence of Sii was significantly higher in consumers of artisanal butter compared with non-consumers (57.1% vs 10.1%, odds ratio OR: 11.9, 95% CI: 3.9-36.6), as well as in persons handling livestock (OR = 3.9; 95% CI = 1.6-9.3) and livestock primary products (OR = 5.7; 95% CI = 2.3-14.3). The closer contact with livestock was a risk factor for Sii fecal carriage. Sii strains were isolated from fresh and fermented milk products with a prevalence of 30.4% and 45.4%, respectively. Analysis of Sii population structure through the SBSEC multi locus sequence typing assay revealed a close relationship across human and dairy isolates, possibly linked to a Kenyan human isolate. All these outcomes underline the interest of in-depth investigations on the ecology, potential reservoirs and pathways of contamination by Sii at the human-animal-environment interface in comparison to yet to be collected data from Europe, Asia and the Americas to further elucidate the various roles of Sii

Dietary aflatoxin exposure of lactating mothers of children 0–6 months in Makueni County, Kenya

Abstract The southeastern region of Kenya is prone to aflatoxin outbreaks, yet maternal and infant aflatoxin intake levels remain unclear. We determined dietary aflatoxin exposure of 170 lactating mothers breastfeeding children aged 6 months and below in a descriptive cross‐sectional study involving aflatoxin analysis of maize‐based cooked food samples (n = 48). Their socioeconomic characteristics, food consumption patterns and postharvest handling of maize were determined. Aflatoxins were determined using high‐performance liquid chromatography and enzyme‐linked immunosorbent assay. Statistical analysis was conducted using Statistical Package Software for Social Sciences (SPSS version 27) and Palisade's @Risk software. About 46% of the mothers were from low‐income households, and 48.2% had not attained the basic level of education. A generally low dietary diversity was reported among 54.1% of lactating mothers. Food consumption pattern was skewed towards starchy staples. Approximately 50% never treated their maize, and at least 20% stored their maize in containers that promote aflatoxin contamination. Aflatoxin was detected in 85.4% of food samples. The mean of total aflatoxin was 97.8 μg/kg (standard deviation [SD], 57.7), while aflatoxin B1 was 9.0 μg/kg (SD, 7.7). The mean dietary intake of total aflatoxin and aflatoxin B1 was 7.6 μg/kg/b.w.t/day (SD, 7.5) and 0.6 (SD, 0.6), respectively. Dietary aflatoxin exposure of lactating mothers was high (margin of exposure < 10,000). Sociodemographic characteristics, food consumption patterns and postharvest handling of maize variably influenced dietary aflatoxin exposure of the mothers. The high prevalence and presence of aflatoxin in foods of lactating mothers are a public health concern and calls for the need to devise easy‐to‐use household food safety and monitoring measures in the study area

Microbial Quality and Safety of Traditional Fermented Camel Milk Product Suusac Sampled from Different Regions in North Eastern, Kenya

Aim: The study was carried out to assess the microbial quality and safety of fermented camel milk product (Suusac) from North Eastern Kenya. Methodology: Twenty-eight samples (n=28) of Suusac from different areas of the region sold in informal markets at Eastleigh in Nairobi were aseptically collected at the sales points. The quality and safety of the Suusac with reference to selected pathogens namely E. coli, S. aureus, Shigella, and Klebsiella spp was evaluated using the standard analytical methods. Results: Escherichia coli were detected in all the samples while Staphylococcus aureus was detected in 63.09% of the samples analyzed. Shigella spp was detected in 88.1% of the samples analyzed and Klebsiella spp was detected in 77.4% of the samples. The mean log10 counts for E. coli, S. aureus, Shigella, and Klebsiella spp were 3.135, 2.576, 2.784 and 3.138, CFUmL-1, respectively. There is a potential public health concern posed by Suusac which is sold for direct consumption due to the presence of the life-threatening bacterial pathogens. Conclusion: The Suusac being sold at Eastleigh market in Nairobi from North Eastern Kenya may be responsible for transmission of the pathogens to the consumers. Training on food hygiene, improving production technology, hygienic conditions and implementing the food legislations along the value chain can minimize the risk

Investigating the association between African spontaneously fermented dairy products, faecal carriage of Streptococcus infantarius subsp. infantarius and colorectal adenocarcinoma in Kenya

Consumption of traditional fermented dairy products (tFDP) in Africa leads to the ingestion of up to 10(8) Streptococcus infantarius subspecies infantarius (Sii) per millilitre of spontaneously fermented milk Sii is a member of the Streptococcus bovis/Streptococcus equinus complex (SBSEC) for which some members are associated particularly with colorectal cancer or endocarditis. The extent of health risks to tFDP consumers is largely unknown. A hospital-based unmatched case-control study was conducted at Kenyatta National Hospital, Nairobi (Kenya) on 80 cases and 193 controls that were selected exhaustively from patients attending colonoscopy at the hospital. Logistic regression models adjusted for age, sex and residency were used in the statistical analysis. Consumption of tFDP was not associated with CRC (odds ratio (OR) 1.4; 95% Confidence interval (CI) 0.7-2.7; p = 0.34). Risk factors associated with CRC included age above 40 years, and consumption of processed meat and alcohol. Faecal carriage of Sii was significantly higher in persons with colon tumours and polyps compared to controls (8.4% vs 21.6%: OR: 4.6; CI 1.3-15.9). Patients with haemorrhoids represented an unexpected carrier group with significantly higher Sii faecal carriage (30.4%, CI: 17.7-45.8). Consumption of tFDP does not represent risk factors for CRC whereas Sii seems to be associated with CRC. However, there is urgent need to assess this finding also in the general population, investigate the causality of SBSEC, Sii and CRC as well as compare the phylogenetic, functional and genomic relationship between human and dairy Sii with regards to the ongoing application of Sii in FDP production