RESUMO
Among the Cronobacter genus, Cronobacter sakazakii is the most common species posing a severe health risk for newborns, infants and children. Some infant formulas, cereal-based foods, and food production environments may be the potential reservoirs of C. sakazakii. This pathogen possesses different virulence factors encoded by different virulence genes. Therefore, characterizing these genes is important for distinguishing pathogenic strains from nonpathogenic ones. The objective of this study was to characterize some virulence genes [OmpA, OmpX, zpx, and Cpa] by real-time polymerase chain reaction (PCR) in C. sakazakii isolates from a total of 120 samples (20 each of milk powder, starch, rice flour, semolina, infant formula and dust samples from food production environments). Overall, 13 isolates (7 from milk powder, 2 rice flour, 1 semolina, and 3 dust) were cultured, identified by bioMérieux API® 20E test kit, and then subjected to real-time PCR application for screening the target virulence-associated genes. Our results showed that all of 13 isolates were positive for the virulence genes OmpA, OmpX, zpx, and Cpa. In summary, our study revealed that some of the analyzed foods and environmental samples were contaminated with pathogenic C. sakazakii with its virulence-associated markers, far above the allowable limit; and therefore, this level of contamination may pose a severe health threat for newborns, infants, and children.(AU)
Dentre o gênero Cronobacter, Cronobacter sakazakii é a espécie mais comum que representa um grave risco para a saúde dos recém-nascidos, bebês e crianças. Algumas formulas infantis para crianças, alimentos a base de cereais e locais de produção de alimentos, foram considerados como potenciais locais de contaminação de C. sakazakii. Este patógeno possui diferentes agentes de virulência codificados por diferentes genes de virulência. Portanto, a caracterização dos genes é importante para distinguir as cepas patogênicas das não patogênicas. O objetivo deste estudo foi caracterizar os diferentes genes de virulência [OmpA, OmpX, zpx, and Cpa] em C. sakazakii isolados em um total de 120 amostras (20 de cada uma delas - leite em pó, amido, farinha de arroz, sêmola, comida para bebês e amostras de poeira provenientes dos ambientes de produção de alimentos) por reação em cadeia da polimerase em tempo real (RT-PCR). No total, foram cultivadas 13 estirpes (7 de leite em pó, 2 de farinha de arroz, 1 de sêmola e 3 poeiras) e depois identificadas pelo kit de teste bio Mérieux API® 20E. As estirpes identificadas foram submetidas ao PCR em tempo real para caracterizar os genes alvo associados à virulência. Os resultados mostraram que todos os genes C. sakazakii isolados eram patogênicos e positivos às OmpA, OmpX, zpx e Cpa com um padrão de coexistência. Em resumo, o nosso estudo revelou que os alimentos e os ambientes de produção de alimentos analisados constituíam uma ameaça à saúde dos recém-nascidos, bebês e crianças devido à contaminação por C. sakazakii patogênico como marcadores associados à virulência.(AU)
Assuntos
Humanos , Recém-Nascido , Lactente , Criança , Cronobacter sakazakii , Infecções por Enterobacteriaceae/transmissão , Fatores de Virulência , Alimentos Infantis/virologia , Grão Comestível/virologia , Turquia , Reação em Cadeia da PolimeraseRESUMO
OBJECTIVE: HIV transmission has been associated with offering a child food prechewed by an HIV-infected caregiver. We assessed awareness of prechewing and oral prewarming of food by an adult before offering it to a child among HIV-infected pregnant women and clinical investigators in 3 Latin American countries. METHODS: HIV-infected pregnant women at 12 sites (Eunice Kennedy Shriver National Institute of Child Health and Human Development International Site Development Initiative Perinatal Longitudinal Study in Latin American Countries, a prospective cohort trial) in Argentina, Brazil, and Peru were administered a screening survey about prechewing/prewarming of infant foods and cautioned against these feeding practices. Survey responses were analyzed, overall, and stratified according to country. RESULTS: Of the 401 HIV-infected pregnant women interviewed, 34% had heard about prechewing (50% from Argentina, 32% from Brazil, and 36% from Peru), 23% knew someone who prechewed food for infants, and 4% had prechewed food in the past. Seventeen percent had heard about oral prewarming of food, 13% knew someone who prewarmed food for infants, and 3% had prewarmed food for an infant in the past. Women who reported knowing someone who prechewed were more likely to also know someone who prewarmed food (P < .0001). Few site investigators anticipated that their patients would be aware of these practices. CONCLUSIONS: Prechewing food, a potential risk factor for HIV transmission, and orally prewarming food, which has not been associated with HIV transmission but might expose a child to blood from an HIV-infected adult, are not uncommon practices in Latin America. Both practices should be further investigated. Site investigator responses underscore that health care providers could be missing information about cultural practices that patients may not report unless specifically asked.