Microbiological quality of meals in collective catering in Ouagadougou: Essential hygiene practices and public health challenges

 Corresponding author: Hadiza BAWA IBRAHIM. Copyright © 2025 Author(s) retain the copyright of this article. This article is published under the terms of the Creative Commons Attribution License 4.0. Microbiological quality of meals in collective catering in Ouagadougou: Essential hygiene practices and public health challenges Hadiza BAWA IBRAHIM 1, 2, *, Soutongnooma Caroline BOUDA 2, Mahamadou Bello ISSA ADAM 3, Aboubakar OUMAR ALI 2 and Nicolas BARRO 2 1 Department of Life and Earth Sciences /University Lédéa Bernard OUEDRAOGO (ULBO) / Burkina Faso 2 Molecular Biology Laboratory for Epidemiology and Surveillance of Bacteria and Viruses Transmitted by Food and Water/Department of Life and Earth Sciences/University Joseph KI-ZERBO (UJKZ) / Burkina Faso 3 Laboratory of Biochemistry, Biotechnology, Food Technology and Nutrition / Department of Life and Earth Sciences/University Joseph KI-ZERBO (UJKZ) / Burkina Faso GSC Advanced Research and Reviews, 2025, 25(01), 120-129 Publication history: Received on 01 September 2025; revised on 16 October 2025; accepted on 18 October 2025 Article DOI: https://doi.org/10.30574/gscarr.2025.25.1.0308 Abstract Collective catering plays a crucial role, but meal inspections are often insufficient, posing a significant health risk. These meals can be contaminated by pathogenic microorganisms, such as Escherichia coli, Salmonella spp., Staphylococcus aureus, and Shigella sp., which are responsible for many foodborne illnesses. This study aims to assess compliance with good hygiene practices and the microbiological quality of meals in collective restaurants in Ouagadougou, Burkina Faso. Field investigations were conducted to observe hygiene practices and collect samples for analysis. A total of 85 samples of meals and utensils were taken at various points along the service chain and immediately transported to the laboratory at 4°C. These samples were analysed using standard microbiological methods to detect the presence of the mentioned pathogens. The results revealed widespread non-compliance with good hygiene practices. Microbiological analyses revealed that nearly all samples were contaminated, with 97.5% containing at least one pathogen. The primary contaminants were 31/85 (36.47%) for Escherichia coli, 7/85 (8.23%) for Salmonella spp., 8/85 (9.41%) for Shigella sp., and 29/85 (34.11%) for Staphylococcus aureus. Of the 85 samples, 75 showed contamination or co-contamination, representing 88.23%. These findings highlight a high health risk for consumers and emphasise the need to intensify hygiene measures. It is essential to raise awareness and train catering professionals to reduce the prevalence of pathogens and ensure food safety. Keywords: Collective catering; Hygiene practices; Microbiological quality; Public health; Ouagadougou/Burkina Faso 1. Introduction The collective catering sector, particularly street food, has established itself as a key activity in meeting the nutritional needs of the working population. These establishments provide over 80% of city dwellers with access to quick and affordable meals [1, 2]. However, the lack of rigorous health controls and inadequate hygiene practices increases the risk for consumers of contracting foodborne illnesses [3]. Consuming food contaminated with pathogens such as Escherichia coli (E. coli), Salmonella spp., Shigella sp., or Staphylococcus aureus (S. aureus) can lead to mild disturbances or more serious illnesses [4-6]. In Burkina Faso, the sector of collective catering has experienced significant growth, providing a large number of meals daily in Ouagadougou. Although its socio-economic importance is vital, hygiene remains a significant concern. Several studies show that sanitary rules are often neglected due to the high volume of meals prepared, the low level of staff GSC Advanced Research and Reviews, 2025, 25(01), 120-129 121 training, and an unsanitary environment [7-10]. These shortcomings facilitate the multiplication and spread of microorganisms. In this context, this study was conducted to document good hygiene practices and to assess the microbiological quality of meals in collective catering in Ouagadougou. It aims to understand the health risks in this sector better and provides key data for the implementation of preventive measures. 2. Materials and methods 2.1. Framework and type of study This prospective and cross-sectional study was conducted in Ouagadougou, the capital of Burkina Faso, from June to November 2024. It involved six sites of collective catering: Dassasgho, Zone 1, Kossodo, Wemtengha, Zogona, and Patte d'oie. The aim was to assess the hygienic and microbiological quality of the meals served at these locations. The populations studied included restaurant staff and consumers. 2.2. Data collection and surveys Hygiene practices were assessed using surveys that employed the 5M method of Ishikawa (Manpower, Material, Method, Equipment, Environment). A structured questionnaire was used to observe the manufacturing process, equipment handling, utensil cleaning, food storage, as well as the overall condition of the environment, the cleanliness of clothing, and waste management. In total, 70 consumers were also surveyed via an evaluation form to gather their perceptions of hygiene, using a scoring grid (Poor, Good, Very Good, Excellent). The questionnaires were administered to both staff and consumers, with an oral explanation provided for those who were not literate. 2.3. Microbiological analyses 2.3.1. Preparation of samples and decimal dilutions To prepare the samples, 25 g were weighed using a balance and then placed into a bottle containing 225 mL of Buffered Peptone Water (BPW). This mixture was shaken for 3 to 5 minutes to release the microorganisms. Subsequently, serial dilutions were performed using sterile pipettes: 1 mL of the previous solution was transferred into 9 mL of BPW to obtain a 10-1 dilution. 2.3.2. Research and identification of microorganisms The analyses involved identifying and quantifying several pathogenic germs. Regarding the search for Salmonella and Shigella, their isolation and identification were carried out according to the ISO 6579-1:2017 standard. The procedure included a non-selective pre-enrichment step in the EPT (incubation at 37 °C for 18-24 hours), followed by selective enrichments in Müller-Kauffmann tetrathionate and novobiocin (MKTTn) broth, as well as modified RappaportVassiliadis (RVS) broth. Isolation was performed on Xylose Lysine Deoxycholate (XLD) and Salmonella-Shigella (SS) agar plates. Suspected colonies were selected, purified, and then identified using a basic biochemical gallery (urease, indole, oxidation, and Kligler-Hajna tests) before being confirmed with the API 20E gallery. The isolated strains were stored at -20 °C in brain-heart infusion (BHI) broth with 20% glycerol. E. coli detection: The search for E. coli was carried out by inoculating 0.1 mL of the dilutions onto Eosin and Methylene Blue (EMB) agar, followed by incubation at 42 °C for 24 hours. Suspect colonies (green with a metallic sheen) were subjected to a minimal biochemical panel for identification (urease test, indole, and Kligler-Hajna tests) and then to the API 20E panel. The strains were preserved in the same manner as those of Salmonella and Shigella. Search for Staphylococcus aureus: Isolation was carried out by spreading 0.1 mL of the mother solution onto a BairdParker (BP) agar plate and incubating it at 37 °C for 24 to 48 hours. Suspect colonies (black, shiny, with a clear halo) were purified on a Muller-Hinton medium. A coagulase test was then performed to confirm the identification of the Staphylococcus aureus species, in accordance with the AFNOR XP V 08-057-1 standard. 2.4. Interpretation criteria The analysis of the results was carried out in accordance with the criteria of the French Standardisation Association (AFNOR). For Salmonella spp. and Shigella sp., any detection in 25 g of sample indicates that the meal is unfit for consumption, according to standard NF V 08-052. Concerning Staphylococcus aureus, the meal is deemed non-compliant GSC Advanced Research and Reviews, 2025, 25(01), 120-129 122 if the number of colonies reaches or exceeds 102, in accordance with standard NF V 08-057-1. The detection of E. coli serves as an indicator of faecal contamination. 2.5. Statistical analysis The data collected was entered and analysed using Microsoft Excel and SPSS software. 3. Results 3.1. Observations on the environment and hygiene of establishments The inspection of catering sites revealed numerous non-compliances with good hygiene practices. The survey results show a mixed perception among consumers: 60% consider the cleanliness of the premises to be 'acceptable', but only 28.57% find it 'very clean'. Similarly, 57.14% of utensils and dishes are deemed 'acceptable' in terms of cleanliness, compared to only 15.71% that are 'well clean'. Furthermore, 65.71% of participants observed no significant improvement in sanitary conditions (Table 1). Table 1 Study of the environment of catering sites Variables Terms Frequency Percentage (%) Cleanliness of premises Very clean 0 0 Acceptable 2 25 Not very clean 5 62.5 Not clean 1 12.5 Total 100 Cleanliness of kitchen utensils and dishes Very clean 0 0 Acceptable 3 37.5 Not very clean 3 37.5 Not clean 2 25 Total 10 Raw material Clean property 0 0 Acceptable 2 25 Not very clean 4 50 Not clean 2 25 Total 10 The methods of food storage are inadequate: half of the raw materials are left exposed to the air. An inappropriate mixture of vegetables, meats, and fish has been observed in the refrigerators. Wastewater management is deficient, with the same water sometimes used for all dishwashing operations (Figure 1). These practices significantly increase the risk of cross-contamination and bacterial growth. GSC Advanced Research and Reviews, 2025, 25(01), 120-129 123 Figure 1 Dishwashing operation in the visited restaurants 3.2. Characteristics of staff and consumers 3.2.1. Staff practices The staff observation revealed a deficiency in personal protective equipment, including lab coats, closed-toe shoes, and hairnets. The lack of soap for frequent hand washing directly exposes the food to contamination risks. It was also observed that 100% of the female staff wear a headscarf, a practice that does not replace a hairnet to ensure protection. The lack of professionalism in food handling and manual task execution increases health risks. 3.2.2. Knowledge and habits of consumers The survey reveals that the majority of the population is male (60%, n = 42), with a predominantly undergraduate level of education (45.71%) or a master's degree (34.29%). It is positive to note that 92.86% of consumers have access to information on good hygiene practices, mainly through training (51.43%). Regarding habits, 85.71% of participants occasionally consume these meals, and 67.14% eat them on-site. The use of sachets as containers is widespread (74.29 %), which poses a hygiene risk. The majority prefer hot meals (94.29 %). 3.2.3. Consumer satisfaction and characteristics of the samples Figure 2 Consumer satisfaction level regarding the served meals Regarding satisfaction, 67.14% of consumers find it 'good', while a notable percentage (27.14%) perceive it as 'bad'. Only 4.28% rate it as 'very good' and 1.42% as 'excellent' (Figure 2), which suggests there is room for improvement. GSC Advanced Research and Reviews, 2025, 25(01), 120-129 124 3.3. The different meals served in collective catering sites The study analysed a total of 85 samples, including 77 meals and eight utensils. The tested dishes represented a wide variety of traditional meals (beans, rice, various sauces, etc.). The temperature of the meals at the time of purchase varied significantly, ranging from 7 °C to 80 °C. Table 2 presents the list and number of different foods collected, along with the temperature at the time of purchase. Table 2 Sampled different dishes Food/meals/materials Temperature °C/Sample Number of samples collected by restaurant type Beans 55 - 62.2 4 Rice with peanut sauce 57 - 74 5 Porridge 57.1 1 Fatty rice 44.8 - 80 3 Yoghurt 22 - 26 3 Degué small millet 21 - 32 5 Degué couscous 7 - 30 3 Cakes 35 - 37 3 Salad 36.6 - 37 6 Atieké 32 - 50.3 7 Degué 24 - 26 7 Macaroni + raw vegetables 37 - 36.6 2 Alloco 38 1 Babenda 63 1 Chilli - 1 Couscous beans 48.8 - 66 3 Rice with tomato sauce 58 - 55 2 Fish sandwich 37 1 Wheat flour cakes 66 1 Powdered milk - 2 Bean soup 37.3 1 Spaghetti with soumbala 36 1 Rice with vegetable sauce 65 - 62 2 Spaghetti/shell pasta 62.2 1 Plates - 3 Spoons - 2 Bowl of degué 36 1 Tray 36 1 Sauce bowl - 1 Potato stew 40 1 Beans and rice 40 1 GSC Advanced Research and Reviews, 2025, 25(01), 120-129 125 Bean sauce 40 1 Spaghetti 38 1 Raw vegetables 32 1 Couscous 40 1 Fish 37 1 Atiéké sauce 32 1 Total 85 3.4. Microbiological quality of food and utensils Microbiological analyses revealed a high level of contamination in the samples. Out of 85 samples, 75 cases, or 88.23%, showed contamination. E. coli was the most frequently isolated germ, with a prevalence of 36.47%, followed by Staphylococcus aureus (34.11%), Shigella sp. (9.41%), and Salmonella spp. (8.23%) (Table 3). This high presence of E. coli is a clear indicator of faecal contamination and a widespread lack of adherence to good hygiene practices. Table 3 Distribution of germs isolated in the sample dishes Germs sought Number (n=85) Frequency % E. coli 31 36.47 Staphylococcus aureus 29 34. 11 Shigella sp. 8 9, 41 Salmonella spp. 7 8.23 Total contamination and co-contamination 75 88.23 3.4.1. Distribution of germs by sample type The study revealed varied contamination levels depending on the categories of food and utensils analysed. Utensils Among the eight utensils analyzed, 5 showed contamination, with the most common germ being Staphylococcus aureus, at a prevalence of 62.5%. One case of Salmonella spp. and another of Shigella sp. were also isolated (Table 4). These results highlight the role of utensils as vectors of cross-contamination. Table 4 Distribution of germs isolated from restaurant utensils Utensils Number Pathogens tested for E. coli Salmonella spp. Staphylococcus aureus Shigella sp. Plates 3 - 01 01 01 Spoons 2 - - 01 - Sick bowl 1 - - 01 - Plateau 1 - - 01 -- Sauce bowl 1 - - 01 - Total 08 - 01 05 01 GSC Advanced Research and Reviews, 2025, 25(01), 120-129 126 Meal based on cereals and starchy foods Among the 23 samples analyzed, E. coli was the most common, at 39.13%, followed by Staphylococcus aureus at 26.08% and Shigella sp. at 17.39%. A case of Salmonella spp. was also identified (Table 5). Table 5 Distribution of germs isolated in cereal and starchy food meals Food/meals Number Pathogens sought E. coli Salmonella spp. Staphylococcus aureus Shigella sp. Peanut sauce Riz 5 01 01 - 01 Fat rice 3 01 - - - Atieké 7 02 - 02 01 Atiéké sauce 1 01 - 01 - Macaroni + raw vegetables 2 01 - - - Rice with vegetable sauce 2 01 - 01 01 Spaghetti or coquillette 1 - - - - Spaghetti 1 01 - 01 01 Couscous 1 01 - 01 - Total 23 09 01 06 04 Meal based on legumes Among the 10 legume samples, significant contamination was identified: 50% by Staphylococcus aureus, 40% by E. coli, and 10% by Salmonella spp.. Table 6 Distribution of germs isolated from leguminous meals Food/meals Number Pathogens tested for E. coli Salmonella spp. Staphylococcus aureus Shigella sp. Beans 4 02 - 01 - Couscous beans 3 01 01 01 - Beans and rice 1 - - 01 - Bean soup 1 - - 01 - Bean sauce 1 01 - 01 - Total 10 04 01 05 - Meal based on dairy products Contamination was identified in 21 samples. Staphylococcus aureus was present in 28.57% of cases, followed by E. coli (19.04%) and Shigella sp. (4.76%) (Table 7). GSC Advanced Research and Reviews, 2025, 25(01), 120-129 127 Table 7 Distribution of germs isolated from dairy-based meals Foods/meals Number Pathogens tested for E. coli Salmonella spp. Staphylococcus aureus Shigella sp. Yoghurt 3 - - - - Degué small millet 5 01 01 Degué couscous 3 01 - - - Degué 8 02 - 03 - Powdered milk 2 - - 03 - Total 21 04 - 06 01 Meal based on fruits and vegetables Seven samples of fruits and vegetables, particularly in salads and raw vegetables, were collected. The identified pathogens include E. coli in 4 cases (57.14%), Salmonella spp. in 2 cases (28.57%), and Staphylococcus aureus in 2 cases (28.57%). Meal based on meat and mixed products Contamination has been detected in all meat product samples (by E. coli and Staphylococcus aureus). Mixed meals showed the presence of various pathogens, highlighting the risk associated with the complexity of the dishes. 4. Discussion Field inspections have uncovered apparent non-compliance with Good Hygiene Practices (GHP) in collective restaurants in Ouagadougou. The staff have limited appropriate protective gear, such as aprons or hairnets. The premises are poorly maintained, infested with pests, and the food storage methods are inadequate. More than half of the raw materials are stored outdoors, and the cold chain is frequently broken. These findings support several studies, notably those by some authors, which highlight that poor environmental hygiene contributes to food contamination [11, 12]. Microbiological analysis reveals a direct link between poor practices and health risks. The most prevalent pathogen is E. coli (36.47%), indicating faecal contamination and inadequate personal and environmental hygiene. The presence of Staphylococcus aureus (34.11%) is also concerning, as it is often associated with human contamination by food handlers through their hands, hair, and nasal passages. This supports our observations regarding the lack of protective equipment and poor handwashing practices. Our findings align with similar studies in Algeria, such as those by [13-16], which all reported a high occurrence of these germs in meals. Although most served meals are hot, often exceeding 50°C, pathogenic bacteria such as Salmonella spp. and Shigella sp. have been found in 8.23% and 9.41% of samples, respectively. This result, which differs from [17], who detected none of these bacteria, is likely due to post-cooking contamination. According to the United Nations Food and Agriculture Organization and World Health Organization, temperatures above 70°C are sufficient to kill most bacteria, indicating that their presence likely results from improper handling or cross-contamination after cooking [2]. This aligns with [18], who showed that cooked foods are at high risk when handled without proper sanitary precautions. The detection of germs indicating faecal contamination and pathogens in the majority of analysed meals indicates a significant public health problem in Ouagadougou. Previous research in Burkina Faso has already indicated that legumes are among the high-risk products, which is confirmed by our results [19]. Furthermore, our observations support those of [20], who demonstrated that poorly washed vegetables can be sources of contamination. These findings emphasise the urgent need to raise awareness and train catering staff in good hygiene practices, in order to significantly reduce the presence of pathogenic agents and ensure the food safety of consumers. GSC Advanced Research and Reviews, 2025, 25(01), 120-129 128 5. Conclusion This study highlights that meals served in collective catering establishments in Ouagadougou pose significant public health risks. On-site investigations revealed frequent violations of good hygiene practices (GHP), including the lack of proper uniforms, improper food storage, and inadequate environmental management. These hygiene issues are confirmed by microbiological analyses, which show high contamination levels in meals and utensils. Pathogens such as E. coli, Salmonella spp., Shigella sp., and Staphylococcus aureus were identified, confirming the risk of food poisoning. Based on these results, it is crucial to take immediate corrective actions. Continuous staff training and enhanced health surveillance are necessary. These steps will significantly reduce contamination risks and enhance food safety for consumers in Ouagadougou/Burkina Faso. Compliance with ethical standards Acknowledgments We express our gratitude to the managers of collective restaurants for their cooperation in this study. We also extend our thanks to the vendors interviewed for their willingness to participate. 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