"We never boil our milk, it will cause sore udders and mastitis in our cows"- consumption practices, knowledge and milk safety awareness in Senegal.

BACKGROUND: Milk is a nutrient-rich food that makes an important contribution to diets in several Low and Middle Income Countries such as Senegal. Milk can also harbour several pathogenic microorganisms. As in other low and middle income countries, the dairy industry in Senegal is growing, with an expansion of farms to meet rapidly growing demand in the cities. However, most of the production still happens in the informal sector, and little is known about consumption of milk and milk products, or knowledge, awareness and practices of actors in informal dairy supply chains. METHODS: We conducted structured focus group discussions with dairy farmers and milk processors in three selected regions (Dakar, Thies and Fatick) in Senegal to investigate the consumption practices, awareness of milk borne hazards, and practices relevant to the risk of milk contamination to gain a deeper understanding of drivers of milk-borne diseases. Data on the consumption of milk and milk products were also collected using a closed questionnaire. RESULTS: Results indicate that milk is an important part of the diet in the study regionsand raw milk consumption is very common. The most common milk product consumed was fermented milk. Awareness of milk borne hazards was limited. Several farmers and processors reported risky practices, despite being aware of better practices, due to cultural beliefs. In households, children, pregnant women and older people were prioritised when milk and milk products were distributed. Dairy farmers and milk processors were more concerned with the lack of food for animals, low production and seasonality of production than the safety of the milk and milk products. CONCLUSIONS: Lack of awareness of milk borne infections and some traditional practices put milk and milk product consumers in the study area at high risk of milk borne diseases.. Prioritising certain sub population at households (Pregnant women and children) makes then vulnerable to milk-borne hazards. It will be challenging to change the risky practices as they are motivated by cultural beliefs hence the best strategy to promote milk safety will be to encourage the boiling of milk by consumers.

Brucellosis in dairy herds: A public health concern in the milk supply chains of West and Central Africa.

Ten herd-level cross-sectional studies were conducted in peri-urban dairy production areas of seven West and Central African countries (Burkina Faso, Burundi, Cameroon, Mali, Niger, Senegal and Togo). The objectives were to estimate herd level Brucella spp. seroprevalence and identify risk factors for seropositivity. In each of the ten study areas, herds (between 52 and 142 per area, total = 965) were selected probabilistically and a structured questionnaire was administered to gather information on their structure and management. A bulk milk sample from each herd was tested by indirect ELISA for Brucella spp. For each area, herd seroprevalence estimates were obtained after adjusting for the assumed performance of the diagnostic test. Herd level risk factors for Brucella spp. seropositivity were identified by means of stratified logistic regression, with each peri-urban zone as a stratum. Area-specific models were also explored. Estimated herd seroprevalences were: Lomé (Togo) 62.0% (95% CI:55.0-69.0), Bamako (Mali) 32.5% (95% CI:28.0-37.0), Bujumbura (Burundi) 14.7% (95%CI:9.4-20.8), Bamenda (Cameroon) 12.6% (95% CI:7.6-21.9), Ouagadougou (Burkina Faso) 3.0% (95% CI:1.0-9.1), Ngaoundere (Cameroon) 2.3% (95% CI:1.0-7.0), Thies (Senegal) 1.3% (95% CI:0.1, 5.3), Niamey (Niger) 1.2% (95% CI:0.08-5.3), Dakar (Senegal) 0.2% (95% CI:0.01-1.7) and Niakhar (Senegal) <0.04%. Logistic regression modelling revealed transhumant herds to be at lower risk of infection (adjusted OR: 0.25, 95% CI: 0.13 - 0.5) and in one of the areas (Bamenda), regular purchase of new animals was found to be strongly associated with Brucella spp. seropositivity (adjusted OR = 5.3, 95% CI: 1.4-25.9). Our findings confirm that Brucella spp. circulates among dairy cattle supplying milk to urban consumers in West and Central Africa, posing a serious public health concern. Control programs are urgently needed in areas such as Lomé or Bamako, where more than 30% of the herds show evidence of infection.

Comparative assessment of fluorescence polarization and tuberculin skin testing for the diagnosis of bovine tuberculosis in Chadian cattle.

Effective surveillance of bovine tuberculosis (BTB) in developing countries where reliable data on disease prevalence is scarce or absent is a precondition for considering potential control options. We conducted a slaughterhouse survey to assess for the first time the burden of BTB in Southern Chad. Altogether, 954 slaughter animals were consecutively sampled and tested using the single intra-dermal comparative cervical tuberculin (SICCT) test, a recently developed fluorescence polarization assay (FPA) and routine abattoir meat inspection after slaughter. Gross visible lesions were detected in 11.3% (CI: 9.4-13.5%) of the animals examined and they were mostly located in the lymph nodes and the lung. Significantly more Mbororo zebus (15.0%) were affected by lesions than Arab zebus (9.9%; OR=2.20, CI: 1.41-3.41%; p<0.001). Of all animals tested, 7.7% (CI: 6.2-9.6%) reacted positively to SICCT if OIE guidelines were applied. However, receiver operating characteristic (ROC) analysis using Mycobacterium tuberculosis complex (MTBC) infected animals as the positive population and lesion negative animals as the negative population, revealed a better SICCT performance if the cut-off value was decreased to >2mm. SICCT reactor prevalence rose to 15.5% (CI: 13.3-18.0%) and FPA did not perform better than SICCT, when this setting adapted cut-off was applied.

Antimicrobial resistance of Salmonella isolated from poultry carcasses in Dakar (Senegal)

This study was undertaken to estimate the antimicrobial resistance of Salmonella isolated from raw chicken. From November 2003 to April 2004 a total of 120 chicken carcasses were collected from 36 randomly selected sale points (supermarkets, traditional market, poultry slaughter house, flocks) in the urban and periurban zones of Dakar, Sénégal, and examined for the presence of Salmonella. Salmonella was isolated from 75 (62.5 percent) of the examined samples. Out of the 90 Salmonella isolates obtained, twenty one serotypes were identified, from which the most prevalent were S. Kentuchy 30 percent, S. Muenster (13.3 percent), S. Brancaster (8.8 percent), S. Enteritidis and S. Hadar (6.6 percent). All Salmonella isolates were tested for their susceptibility to 16 selected antimicrobial agents by the agar diffusion method. Seventy one (78.9 percent) isolates were resistant to one or more antimicrobials. Out of 71 resistant Salmonella isolates, 33 (46.5 percent) showed multiple resistance to five or more different antimicrobials. Resistance to ampicillin, trimethoprim, trimethoprim-sulphamethoxazole, tetracyclin and sulphonamides was the most frequent. We found 36 different patterns of multiresistant strains. The high level of antibiotic resistance of foodborne Salmonella isolates in the present study is an indication of indiscriminate and continuous use of subtherapeutic doses of antibiotics in animals. Furthermore, the results showed the possible significance of chicken meat as a source of multiple antimicrobial-resistant Salmonella for human infections and suggest the need for detailed epidemiological study.

O presente estudo foi realizado com o propósito de aviliar a resistência aos antibióticos dos sorovares da Salmonella isolados da carne de frango crua. De novembro de 2003 até abril de 2004, um total de 120 carcaças de frango foram compradas em 13 pontos de venda e 23 centros de criação de frangos. As Salmonella foram isoladas a partir de 75 (62,2 por cento) carcaças analisadas. Vinte e um (21) sorotipos diferentes foram identificados, sendo os mais freqüentes S. Kentucky (30 por cento), S. Muenster (13,3 por cento), S. Brancaster (8,8 por cento), S. Enteritidis e S. Hadar (6,6 por cento). Todos os sorovares de salmonela foram examinados a fim de determinar a resistência à 16 antibióticos. Setenta e quatro (79,6 por cento) foram resistentes à um antibiotico ou mais, das quais 33 (45,6 por cento) mostraram resistência múltipla a cinco antibióticos (ampicilina, trimetoprim, trimetoprim-sulfametoxazol, tetraciclina e sulfonamidas). Foram encontrados 36 perfis diferentes de resistência múltipla. O nível elevado de resistência dos isolados de Salmonella encontrados na carne do presente estudo, é um indicador do uso indevido e contínuo de doses subterapêuticas de antibióticos nos animais. Por outro lado, os resultados do estudo demonstram a importância da carne de frango como fonte potencial de sorovares de Salmonella multiresistentes transmissíveis ao homem e sugerem um estudo epidemiólogico detalhado.

Domestic animals as carriers of Bordetella species in Senegal.

Despite intense efforts to maintain a high level of vaccine coverage against human whooping cough, rural senegalese areas are still endemic for Bordetella pertussis. One explanation being the potential existence of animal reservoirs, the objective of this work was to precise the carriage by domestic animals of bacteria belonging to the genus Bordetella in Senegal. Bacteriological samples (swabs and aspirates) were obtained from various domestic animals living in different parts of the country. No B. pertussis nor B. parapertussis were isolated. However, for the first time to our knowledge, B. bronchiseptica was identified from small ruminants located in Africa. The positive animals were two goats and two sheep from Dakar slaughterhouse together with a goat living in a rural compound. The fact that it was identified in goats and sheep underlines the potential zoonotic of that bacterial species in countries where small ruminants are of economical and cultural relevance.