Orientador: Maria Jacira Silva Simões / Banca: José Paschoal Batistuti / Banca: Jonas Contiero / Resumo: A diarréia do viajante é o problema de saúde, mais comum, associado ao turista em termos de freqüência e impacto econômico contribuindo para a perda de rendimentos obtidos pelo turismo, em países em desenvolvimento. O objetivo da presente pesquisa foi identificar os agentes etiológicos mais freqüentes, nos surtos de doença transmitida por alimentos e/ou água em núcleos receptores turísticos, conhecer a sazonalidade e caracterizar a população segundo a idade e os alimentos suspeitos. Baseou-se nas notificações enviadas à Divisão de Doença de Transmissão Hídrica e Alimentar (DDTHA), Centro de Vigilância Epidemiológica (CVE), Secretaria Estadual de Saúde (SES) do Estado de São Paulo, no período 2002 a 2005 e informações das Vigilâncias Sanitárias da Direção Regional de Saúde (DIR). Os núcleos receptores turísticos selecionados foram: cidade de São Paulo e alguns municípios do interior como Águas de São Pedro, Campinas, Campos de Jordão, Franca, Jundiaí, Piracicaba, Pirassununga, Ribeirão Preto, São José dos Campos, São José do Rio Preto e do litoral como Guarujá, Peruíbe, Praia Grande, Santos e Ubatuba. Os resultados mostraram que o núcleo receptor turístico cidade de São Paulo, notificou 304 surtos, 3382 casos/doentes e dois óbitos. Do interior foram notificados 116 surtos e 8016 casos/doentes e três óbitos. Do litoral foram notificados 11 surtos, 253 casos/doentes e três óbitos, compreendendo um total de 431 surtos, sendo 129.340 comensais, 11.651 casos/doentes e 8 óbitos. Os agentes etiológicos mais freqüentes foram : vírus (58,08%), bactérias (72,72%), protozoários (4,67%), helmintos (0,83%), fungos (0,15%) e produtos químicos (0,12%). A freqüência dos agentes etiológicos foi: Rotavirus 31,86%; coliformes 28,38%; Salmonella sp. 13,55% (Salmonella Enteritidis 5,08% e Salmonella Typhimurium 2,88%)... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Travelers' diarrhea is the most common travel-related health problem in terms of frequency and economic impact. Travelers' diarrhea also contributes to loss of income from tourism in developing countries. The aim of the present study was to find the principle pathogens involved in outbreaks of food poisoning in tourist centers, and discover in what season the outbreaks occur, and age of the population. This study was based on informations sent to Divisão de Doença de Transmissão Hídrica e Alimentar (DDTHA), Centro de Vigilância Epidemiológica (CVE), Secretaria Estadual de Saúde (SES) do Estado de São Paulo and Vigilâncias Sanitárias da Direção Regional de Saúde (DIR) from 2002 - 2005. The tourist centers selected for the study were: São Paulo city; Águas de São Pedro, Campinas, Campos de Jordão, Franca, Jundiaí, Piracicaba, Pirassununga, Ribeirão Preto, São José dos Campos, São José do Rio Preto; Guarujá, Peruíbe, Praia Grande, Santos, and Ubatuba. The results showed that São Paulo city reported 304 outbreaks, 3,382 cases/disease and two deaths. From the interior of the state of São Paulo (116 outbreaks), 8016 cases/disease and 3 deaths were registered. From the coast (11 outbreaks), 253 cases/disease and 3 deaths were registered. In total there were 431 outbreaks, 129,340 persons exposed, 11,651 cases/disease and 8 deaths. The etiological agents were bacteria (72.72%), virus (58.08%), protozoa (4.67%), nematodes (0.83%), fungi (0.15%) and chemical products (0.12%). The frequency of causative pathogens was: Rotavirus 31.86%, coliforms 28.38%... (Complete abstract click electronic access below) / Mestre

Submitted by ISAMERY AUXILIADORA MACHADO DE SARMIENTO null (isamerymachado@yahoo.com) on 2016-08-24T00:16:43Z No. of bitstreams: 1 Archivo combinado tese completa con link Isa.pdf: 3685365 bytes, checksum: 2df7162dfd0eb21c6e675c7966fce592 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-08-25T20:40:51Z (GMT) No. of bitstreams: 1 machadodesarmiento_ia_dr_bot.pdf: 3685365 bytes, checksum: 2df7162dfd0eb21c6e675c7966fce592 (MD5) / Made available in DSpace on 2016-08-25T20:40:51Z (GMT). No. of bitstreams: 1 machadodesarmiento_ia_dr_bot.pdf: 3685365 bytes, checksum: 2df7162dfd0eb21c6e675c7966fce592 (MD5) Previous issue date: 2016-06-30 / As doenças de transmissão alimentar (DTA) por bactérias constituem um problema de saúde pública no mundo. O objetivo do trabalho foi identificar por métodos microbiológicos e moleculares a presença de Campylobacter spp., Salmonella spp. e Escherichia coli em frangos de Botucatu-SP, Brasil. Sessenta (60) amostras de frangos resfriados de diferentes marcas foram coletadas aleatoriamente em diferentes estabelecimentos localizados tanto na periferia, quanto no centro da cidade de Botucatu, SP, no período de julho a outubro de 2015. Posteriormente, Campylobacter spp, Salmonella spp e E. coli foram isolados através de métodos microbiológicos convencionais. A confirmação das bactérias isoladas se realizou por provas bioquímicas e PCR. Além disso, as provas para determinar a resistência antimicrobiana e a existência de gene integron classe 1 foram realizadas. Os resultados demostraram a presença de três das principais bactérias que causam doenças de origem alimentar em carcaças de frango provenientes de supermercados e casas de carne de Botucatu. A prevalência de Campylobacter, Salmonella, e E. coli foi 38,3%, 13,3% e 60%, respectivamente. A resistência antimicrobiana dos isolados foi elevada e presença do gene íntegron classe 1 foi identificada em alguns agentes patogénicos. / The transmission of Foodborne Diseases (FBD) by bacteria constitutes a public health problem in the world. The objective of this study was to identify by microbiological and molecular methods the presence of Campylobacter spp., Salmonella spp. and Escherichia coli in broiler chickens at Botucatu, SP, Brazil. Sixty samples of chilled chickens of different brands were randomly collected from supermarkets and meat houses located in both the periphery and the center of the city, in the period from July to October 2015. Later, Campylobacter spp., Salmonella spp., and E. coli were isolated by conventional microbiological methods. Confirmation of the isolated bacteria was performed by biochemical and PCR tests. In addition, proofs to determine antimicrobial resistance and the existence of class 1 integron gene were carried out. Results confirmed the presence of the three assessed bacteria in poultry carcasses from selected establishments. The prevalence was 38.3%, 13.3% and 60% to Campylobacter, Salmonella and E. coli, respectively. Antimicrobial resistance of the isolates was high and the presence of integron class 1 gene has been identified in some pathogens.

Orientador: Noeme Sousa Rocha / Resumo: As doenças de transmissão alimentar (DTA) por bactérias constituem um problema de saúde pública no mundo. O objetivo do trabalho foi identificar por métodos microbiológicos e moleculares a presença de Campylobacter spp., Salmonella spp. e Escherichia coli em frangos de Botucatu-SP, Brasil. Sessenta (60) amostras de frangos resfriados de diferentes marcas foram coletadas aleatoriamente em diferentes estabelecimentos localizados tanto na periferia, quanto no centro da cidade de Botucatu, SP, no período de julho a outubro de 2015. Posteriormente, Campylobacter spp, Salmonella spp e E. coli foram isolados através de métodos microbiológicos convencionais. A confirmação das bactérias isoladas se realizou por provas bioquímicas e PCR. Além disso, as provas para determinar a resistência antimicrobiana e a existência de gene integron classe 1 foram realizadas. Os resultados demostraram a presença de três das principais bactérias que causam doenças de origem alimentar em carcaças de frango provenientes de supermercados e casas de carne de Botucatu. A prevalência de Campylobacter, Salmonella, e E. coli foi 38,3%, 13,3% e 60%, respectivamente. A resistência antimicrobiana dos isolados foi elevada e presença do gene íntegron classe 1 foi identificada em alguns agentes patogénicos. / Abstract: The transmission of Foodborne Diseases (FBD) by bacteria constitutes a public health problem in the world. The objective of this study was to identify by microbiological and molecular methods the presence of Campylobacter spp., Salmonella spp. and Escherichia coli in broiler chickens at Botucatu, SP, Brazil. Sixty samples of chilled chickens of different brands were randomly collected from supermarkets and meat houses located in both the periphery and the center of the city, in the period from July to October 2015. Later, Campylobacter spp., Salmonella spp., and E. coli were isolated by conventional microbiological methods. Confirmation of the isolated bacteria was performed by biochemical and PCR tests. In addition, proofs to determine antimicrobial resistance and the existence of class 1 integron gene were carried out. Results confirmed the presence of the three assessed bacteria in poultry carcasses from selected establishments. The prevalence was 38.3%, 13.3% and 60% to Campylobacter, Salmonella and E. coli, respectively. Antimicrobial resistance of the isolates was high and the presence of integron class 1 gene has been identified in some pathogens. / Doutor

Em um total de 90 amostras de hortaliças, incluindo 30 de alface, 30 de agrião e 30 de escarola, foi verificada a ocorrência de Aeromonas do grupo A. hydrophila, empregando-se os métodos de semeadura direta em ágar amido-amplicilina (contagem) e após enriquecimento em caldo tripticase-soja adicionado de ampicilina (teste de presença/ausência). As incubações foram feitas a 28&#186;C, durante 24 horas. A presença dessas bactérias foi detectada em 43 (47,8%) das amostras analisadas, com contagens variando de < 102 a 2, 0x 106UFC/g. As amostras de agrião foram as que revelaram, na contagem, com maiores números de Aeromonas spp. Das 43 amostras positivas para Aeromonas spp. 9 (21,0%) revelaram-se com números superiores a 104 UFC/g. sendo que 7 eram de agrião . Dentre as amostras de hortaliças analisadas, as de agrião revelaram-se com positividade para Aeromonas do grupo A. hydrophila (70,0%) significativamente maior em relação às de alface (43,3%) e de escarola (30,0%) a nível de 5%. Não foram observadas diferenças significativas entre as positividades obtidas através do método de semeadura direta em placas e do teste de presença/ausência para as amostras de alface e de agrião. Para as amostras de escarola, a positividade foi significativamente mais alta no teste de presença/ausência. Do total de 143 cepas confirmadas como sendo do gênero Aeromonas, 138 (96,5%) eram de A. caviae, 4 (2,8%) de A. hydophila e 1 (0,7%) que, pelas suas características, foi considerada como Aeromonas atipica. Dos resultados obtidos, pode-se depreender que as hortaliças dos tipos analisados, alface, agrião e escarola, dado os níveis de contaminação observados, podem representar risco aos consumidores. / A total of 90 retail vegetable samples, including 30 of lettuce, 30 of water-cress and 30 of escarole were examined for the presence of Aeromonas of the A. hydrophila group, using two different isolation methods. One of the methods envolved direct plating on starch-ampicinin agar for the purpose of enumeration and the other one, after enrichment in trypticase-soy broth with ampicillin, for detection, both using 24 hour incubation at 28&#176C. Aeromonas spp. Were detected in 43 (47.8%) samples and their numbers varied from less than 102 up to 2.0x106 CFU/g. The water-cress samples were the ones to show greater numbers of Aeromonas spp. The counts of 9 (21%) of the 43 positive samples exceeded 104 CFU/g, 7 of them consisting of water-cress. The number of water-cress positive samples (70.0%) was significantly higher at 5% than those of lettuce (43.3%) and those of escarole (30.0%). No significant differences were found in relation to positivity for Aeromonas spp. Between both isolation methods used, regarding the lettuce and the water cress samples. On the other hand, with respect to the escarole samples, positivity was significantly superior for the isolation method envolving enrichment. In therms of species level identification, among 143 strains confirmed as being Aeromonas spp., 138 (96.51%) were A, cavia, 4 (2.81%) were A, hvdrophila and 1 (O,7%) was considered as atypical due to its different biochemical profile. The results show that the vegetables examined may represent risk to consumers in terms of presence and numbers of Aeromonas of the A, hvdrophila group.

Introdução: As doenças transmitidas por alimentos (DTA) constituem um grave problema de saúde pública a nível mundial. A Organização Mundial da Saúde estima que mais de um terço da população, incluindo a dos países desenvolvidos, é acometida por surtos de DTA anualmente, embora a maioria dos casos não seja notificada às autoridades sanitárias locais. Objetivo: Analisar a evolução das DTA nas diferentes regiões do Brasil entre 2000 e 2015. Metodologia: O presente estudo, de caráter descritivo, consistiu na análise de dados do Ministério da Saúde e de artigos científicos que tratam das DTA no contexto nacional, no período de janeiro de 2000 a dezembro de 2015. A primeira fase do estudo foi caracterizada pela coleta de dados sobre DTA disponíveis pelo Ministério da Saúde. Na segunda fase, foi realizado o levantamento e análise geral da produção científica brasileira nas seguintes bases de dados: LILACS, SciELO, Scopus, Web of Science, Pubmed e Embase. E na terceira fase do estudo foi traçado o panorama das DTA nas diferentes regiões do Brasil, relacionando os dados oficiais do Ministério da Saúde com os dados das pesquisas publicadas. Resultados: Entre 2000 e 2015 foram registrados no Ministério da Saúde 11.524 surtos de DTA com 219.909 doentes e 167 óbitos e publicados 50 artigos científicos sobre surtos de DTA no Brasil. Foi possível verificar que a região Sudeste apresentou maior prevalência no número de trabalhos publicados e de surtos de DTA. Na análise dos dados do MS observou-se que os alimentos mistos (12,4 por cento ) foram os mais envolvidos nos surtos, seguidos por aqueles preparados com ovos e produtos à base de ovos (8,7 por cento ); o agente etiológico não foi identificado em 57,8 por cento dos surtos e quando identificado, a Salmonella spp. foi o mais frequente (14,4 por cento ) e a maioria dos surtos ocorreram nas residências (36,6 por cento ). Considerando os dados dos artigos, a água foi o alimento que mais surtos de DTA causou (22 por cento ), o agente etiológico mais estudado foi a Salmonella spp. (22 por cento ) e as residências foram os locais mais envolvidos nos surtos (48 por cento ). Conclusões: Os dados obtidos indicam a necessidade de novas políticas públicas de incentivo a notificação dos surtos, bem como o desenvolvimento de programas de orientação e educação em boas práticas de manipulação de alimentos para a população e estabelecimentos produtores de alimentos / Introduction: Foodborne disease is a significant public health problem worldwide. The World Health Organization estimates that more than a third of the world\'s population, including those living in developed countries, is affected by foodborne disease, although many cases are not reported to the local health authority. Purpose: This study aimed to evaluate the occurrence of foodborne disease around different regions of Brazil between 2000 and 2015. Methodology: This is a descriptive study, based on analysis of data from the Brazilian Ministry of Health and from scientific manuscripts regarding foodborne disease at a national level, occurred between January 2000 and December 2015. Data from both sources were evaluated and compared to map the panorama of foodborne disease outbreaks in Brazil. Results: In the period of 2000 to 2015, a total of 11,524 foodborne outbreaks were reported to the Brazilian Ministry of Health, involving 219,909 cases and 167 deaths. In the same period, 50 manuscripts dealing with this topic were published. The largest prevalence of foodborne outbreaks was observed in the Southeast region of Brazil. Based on data from the Brazilian Ministry of Health, mixed foods were the most involved in the outbreaks (12.4 per cent ), followed by those foods prepared with eggs and egg products (8.7 per cent ). In most of the cases, the etiologic agent was not identified (57.8 per cent ). Among those identified, Salmonella spp. was the most frequent (14.4 per cent ), while homes were the main site of occurrence (36,6 per cent ). Based on data from the manuscripts, water was the most involved in the outbreaks (22 per cent ), while Salmonella spp. was the most reported pathogen (22 per cent ) and homes the main site of occurrence (48 per cent ). Conclusion: Notification of foodborne disease outbreaks is one of the fundamental duties to facilitate public health action and needs to be encouraged

Submitted by Aline Batista (alinehb.ufpel@gmail.com) on 2018-05-24T12:20:42Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Anelise_Bravo.pdf: 334250 bytes, checksum: 202476b6e47db168114279f75ea259d0 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-05-24T13:56:04Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Anelise_Bravo.pdf: 334250 bytes, checksum: 202476b6e47db168114279f75ea259d0 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-05-24T13:56:12Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Anelise_Bravo.pdf: 334250 bytes, checksum: 202476b6e47db168114279f75ea259d0 (MD5) / Made available in DSpace on 2018-05-24T13:56:12Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Anelise_Bravo.pdf: 334250 bytes, checksum: 202476b6e47db168114279f75ea259d0 (MD5) Previous issue date: 2017-07-20 / Sem bolsa / A mussarela de leite de búfala, principal tipo de queijo obtido a partir desse leite no Brasil, é um produto novo no mercado, com alta aceitação pelos consumidores e excelentes perspectivas de comércio. O queijo é um alimento rico em nutrientes, o que favorece a proliferação de micro-organismos que podem provocar toxi-infecções ou intoxicações nos consumidores. A gastrenterite estafilocócica é causada pela ingestão de alimentos que contenham enterotoxinas produzidas por Staphylococcus coagulase positiva. Um problema que pode dificultar a eliminação de microorganismos indesejáveis na indústria de alimentos é a formação de biofilme. O objetivo deste estudo foi determinar o efeito da formação de biofilme por Staphylococcus coagulase positiva (SCP) isolados de queijo mussarela de búfala sobre a sensibilidade a sanitizantes. A partir de contagens de SCP realizadas em 50 amostras de queijo mussarela de búfala foram obtidos isolados, que foram comparados entre si por rep-PCR e identificados bioquimicamente e por multiplex PCR. As cepas distintas foram testadas quanto a formação de biofilme em placas de microtitulação. As cepas forte formadoras e uma não formadora de biofilme foram testadas em superfícies de polietileno de alta densidade, aço inoxidável e vidro. Também foram testadas quanto à sensibilidade ao hipoclorito de sódio e ao iodo após a formação do biofilme. Vinte amostras de queijo albergavam SCP, entretanto as contagens estavam dentro dos limites estabelecidos pela legislação brasileira. A rep-PCR mostrou que cada uma das amostras que estavam contaminadas apresentava uma única cepa, as quais foram identificadas como S. aureus. Dois isolados foram classificados como forte formadores de biofilme, sete como moderados formadores, dez fracos formadores e um como não formador de biofilme. As duas cepas forte formadoras produziram biofilme nas três superfícies testadas. A aplicação dos sanitizantes hipoclorito de sódio e iodo promoveu uma redução das populações bacterianas de aproximadamente 2 log em todas as superfícies, tanto das cepas formadoras de biofilme como da não formadora. Embora as cepas formadoras de biofilme não sejam mais resistentes aos sanitizantes hipoclorito de sódio e iodo do que as não formadoras, elas atingem maiores concentrações no biofilme, o que resulta em maiores populações bacterianas remanescentes após a aplicação dos sanitizantes. / The Buffalo milk mozzarella cheese, main type of chesse obtained from this milk in Brazil, is a new product in the market, with high consumer acceptance and excellent prospects for trade. The cheese is rich in nutrients, which favors the proliferation of microorganisms that can cause food toxi-infections in the consumer. The staphylococcal gastro-enteritis is caused by ingestion of food containing enterotoxins produced by coagulase-positive Staphylococcus. One problem that may hinder the elimination of undesirable microorganisms in the food industry is the formation of biofilms. The objective of this study was to determine the effect of biofilm formation by coagulase-positive (CPS) Staphylococcus isolated from buffalo mozzarella cheese on sensitivity to sanitizers. From CPS counts carried out on 50 samples of buffalo mozzarella cheese were obtained isolates, which were compared by rep-PCR and biochemically identified and by multiplex PCR. The distinct strains were tested for biofilm formation in microtiter plates. Strong forming and non-biofilm forming strains were tested on high density polyethylene, stainless steel and glass surfaces. They were also tested for sensitivity to sodium hypochlorite and iodine after biofilm formation. Twenty samples of cheese harbor CPS, however the counts were within the limits established by Brazilian legislation. Rep-PCR showed that each of the samples that were contaminated had a single strain, which was identified as S. aureus. Two isolates were classified as strong biofilm formers, seven as moderate formers, ten weak formers and one as non-biofilm builder. The two strong forming strains produced biofilm on the three surfaces tested. The application of sodium hypochlorite and iodine sanitizers promoted a reduction of approximately 2 log bacterial populations on all surfaces of both the biofilm and non-forming strains. Although biofilm forming strains are no longer resistant to sanitizers sodium hypochlorite and iodine than non-forming sanitizers, they reach higher concentrations in the biofilm, resulting in larger bacterial populations remaining after application of the sanitizers.

Magister Public Health - MPH / This study is aimed to assess the extent of street food vendor information and education on food safety. Aim: To determine the knowledge, attitudes and practices (KAP) of street food vendors, within the City of Johannesburg, with regard to food hygiene and safety. Methods: A descriptive, cross-sectional study utilizing a quantitative research approach. Data was collected through face-to-face interviewing of street food vendors, with observations of general hygiene and cleanliness. Data was captured in Excel and imported into CDC Epi Info version 3.4.3 (2007) for analysis. Numerical data was analyzed using descriptive statistics and categorical data was analyzed using frequencies. Bivariate analysis was used to establish differences between regions with high and low proportions of street food vendors with regard to knowledge, practices and attitudes variables. / South Africa

Water and food borne Escherichia coli O157:H7 could be one of the pathogens posing high health risk to patients suffering from Acquired Immunodeficiency Syndrome (AIDS) because of its incrimination in diarrhoea cases in AIDS patients. The present study, which was conducted between March 2005 and August 2006, investigated the prevalence of E. coli O157:H7 in water, meat and meat products and vegetables and its impact on diarrhoeic conditions of confirmed and non-confirmed HIV/AIDS patients in the Amathole District in the Eastern Cape Province of South Africa. The water samples used in the study were obtained from stand pipes supplying treated drinking water to communities residing in Fort Beaufort, Alice, Dimbaza and Mdantsane whereas borehole waters were sampled from Ngwenya and Kwasaki. The meat and meat products and vegetable samples were purchased from shops, butcheries, supermarkets and open air markets in Fort Beaufort, Alice and Mdantsane. The stool swabs used in the study were obtained from HIV/AIDS and outpatient clinics at Frere Hospital in East London. A total of 180 each of water, meat and meat products and vegetable samples and another 360 stool samples were analyzed for E. coli O157:H7. Presumptive E. coli O157 was isolated from the samples by culture-based methods and confirmed using Polymerase Chain Reaction techniques. Anti-biogram as well as risk assessment were also carried out using standard methods. The viable counts of presumptive E. coli O157 for water samples ranged between 3.3 × 104 and 1.71 × 105 CFU/ml, and between 1.8 × 104 and 5.04 × 106 CFU/g for meat and meat products, whereas those for vegetables ranged between 1.3 × 103 and 1.6 × 106 CFU/g. The counts of presumptive E. coli O157 for the water and vegetable samples were not significantly different whereas those for meat and meat products were found to be significantly different (P ≤ 0.05). The prevalence rates of presumptive E coli O157 in meat and meat products was 35.55 percent (64/180), and 25.55 percent (46/180) and 21.66 percent (39/180) for water and vegetables respectively. Prevalence of presumptive E. coli O157 in the stool samples of HIV/AIDS patients was 36.39 percent (131/360), of which 56.5 percent (74/131) and 43.5 percent (57/131) were from stools of confirmed and non-confirmed HIV/AIDS patients, respectively. Molecular analysis of representative presumptive E. coli O157 indicated that 10.29 percent (4/39) of vegetables; 14.81 percent (4/27) of water and 38.46 percent (5/13) of meat and meat products carried E. coli O157:H7. Also 36 percent (9/25) and 17.24 percent (5/29) of the stool samples were positive for E. coli O157:H7. Antimicrobial susceptibility profile revealed that all of the E. coli O157:H7 isolated from water, meat and meat products and vegetables as well as those isolated from stools of confirmed and non-confirmed HIV/AIDS patients were resistant (R) to gentamycin and erythromycin. However, 75 percent (20/27) of these isolates were resistant (R) to ampicillin and tetracycline whereas approximately 25 percent (6/27) were resistant (R) to nalidixic acid, ceftriaxone, and chloramphenicol. All the isolates (27/27) were susceptible (S) to amikacin. Probability of risk of E. coli O157:H7 infection was high for confirmed HIV/AIDS patients than for the non-confirmed HIV/AIDS patients. Estimated probability of risk of E. coli O157:H7 due to ingestion of water was 1.00 for 100 confirmed and non-confirmed HIV/AIDS patients. Risk due to meat and meat products was estimated at 0.27 and 0.20 and for vegetables at 0.21 and 0.15 per 100 confirmed and non-confirmed HIV/AIDS patients. The findings of this study predicted a possible link between E. coli O157:H7 isolated from drinking water, meat and meat products and vegetables and diarrhoeic conditions in both confirmed and non-confirmed HIV/AIDS patients, and concludes that confirmed HIV/AIDS patients can be at higher risk of contracting water and food borne E. coli O157:H7 than nonconfirmed HIV/AIDS patients. It is thus recommended that proper water treatment and food handling, maximum food and water safety and sanitation as well as personal body hygiene should be maintained, in order to prevent E. coli O157:H7 infections. Education initiatives and active surveillance of E. coli O157:H7 should be taken by all the stake-holders working directly or indirectly towards ensuring enduring sound public health.

Community-acquired Clostridium difficile infections have recently been increasing in incidence and severity. Several studies have isolated C. difficile spores from livestock and retail meats, suggesting that food may play a role in transmission. No research has been done, however, on what food conditions might allow for the survival and/or growth of the bacterium. We therefore modelled the minimum thresholds for C. difficile growth under low pH, water activity (aw), and temperature. We also sampled retail ground meats, cheese, and milk for the presence of C. difficile spores and subtyped food isolates for comparison with clinical strains. We found that C. difficile growth could be prevented by refrigeration temperatures. C. difficile spores were also detected for the first time in Canada in ground lamb, ground turkey, ground chicken, cheese and milk. The majority of these food isolates were genetically similar to epidemic strain NAP7/078, suggesting that food may not be a direct vector for C. difficile transmission, but could still be clinically relevant.

Rapid detection of foodborne pathogen is one of the most urgent problems in the world, because foodborne pathogen could cause serious illness, such as nausea, vomiting and diarrhea. We have developed a sensitive microfluidic system based on dendrimers and aptamers for rapid detection of Escherichia coli O157:H7 at very low cells concentration. Dendrimers, with high level of functional groups and homogeneous spherical shape, are prefect nanoscale polymers used as a template material by increasing sensitivity and specificity of analytes detection in microfluidics. In this work, we develop a sensitive microfluidic system based on dendrimers and aptamers for detecting Escherichia coli O157:H7 at very low cell concentrations. Carboxyl functionalized G7-polyamidoamine (PAMAM-COOH) dendrimers are immobilized on (3-aminopropyl)-trimethoxysilane (APTMS) pretreated microfluidic channels. The aptamers are subsequently conjugated on the immobilized dendrimes through chemicals. The sensitivity and specificity are validated by injecting fluorescein isothiocyanate (FITC) labelled Escherichia coli O157:H7 at various cells concentration into the resulting microchannels, indicating that the detectable cells concentration can be reached as low as 100 (cells/ml) and the detection time is 10 hours. To further exploit and improve the work efficiency our microfluidic device, the microfluidic channel is designed into a staggered herringbone microchannel (SHM) to create the chaotic dynamics inside the microfluidic device, and the SHM is then simulated by a COMSOL software showing that the staggered herringbone structures can improve chaotic dynamics of designed microchannel and will enhance the probability of particles to attach on the surface of microdevice. All the results show that our approach has the potential to develop the field of rapid and accurate detection on foodborne pathogens.