Víbrios não coléricos na rotina enterobacteriológica

De 3.250 fezes diarréicas, recebidas para diagnóstico microbiológico em laboratório clínico particular, no Recife, Brasil, isolaram-se 55 (1,7%) linhagens de Vibrio. O estudo foi realizado entre maio de 1989 e maio de 1991. Para o isolamento de Vibrio, os espécimes fecais foram enriquecidos em água peptonada alcalina suplementada com 2% de NaCl e subcultivados em ágar tiosulfato-citrato-sais biliares-sacarose (TCBS). Das espécies isoladas, V. parahaemolyticus foi a mais freqüente (24 cepas), seguida de V. furnissii (15 cepas), V. cholerae não 01 (6 cepas), V. alginolyticus (4 cepas), V. fluvialis (2 cepas) e Vibrio sp. (1 cepa). Do ponto de vista custo-benefício, a baixa taxa de isolamento de Vibrio levanta dúvidas acerca da utilidade do TCBS na rotina enterobacteriológica dos laboratórios clínicos

Multiple linear and principal component regressions for modelling ecotoxicity bioassay response

The ecotoxicological response of the living organisms in an aquatic system depends on the physical, chemical and bacteriological variables, as well as the interactions between them. An important challenge to scientists is to understand the interaction and behaviour of factors involved in a multidimensional process such as the ecotoxicological response.With this aim, multiple linear regression (MLR) and principal component regression were applied to the ecotoxicity bioassay response of Chlorella vulgaris and Vibrio fischeri in water collected at seven sites of Leça river during five monitoring campaigns (February, May, June, August and September of 2006). The river water characterization included the analysis of 22 physicochemical and 3 microbiological parameters. The model that best fitted the data was MLR, which shows: (i) a negative correlation with dissolved organic carbon, zinc and manganese, and a positive one with turbidity and arsenic, regarding C. vulgaris toxic response; (ii) a negative correlation with conductivity and turbidity and a positive one with phosphorus, hardness, iron, mercury, arsenic and faecal coliforms, concerning V. fischeri toxic response. This integrated assessment may allow the evaluation of the effect of future pollution abatement measures over the water quality of Leça River.

Optimization of River Water Quality Surveys by Multivariate Analysis of Physicochemical, Bacteriological and Ecotoxicological Data

This study aims to optimize the water quality monitoring of a polluted watercourse (Leça River, Portugal) through the principal component analysis (PCA) and cluster analysis (CA). These statistical methodologies were applied to physicochemical, bacteriological and ecotoxicological data (with the marine bacterium Vibrio fischeri and the green alga Chlorella vulgaris) obtained with the analysis of water samples monthly collected at seven monitoring sites and during five campaigns (February, May, June, August, and September 2006). The results of some variables were assigned to water quality classes according to national guidelines. Chemical and bacteriological quality data led to classify Leça River water quality as “bad” or “very bad”. PCA and CA identified monitoring sites with similar pollution pattern, giving to site 1 (located in the upstream stretch of the river) a distinct feature from all other sampling sites downstream. Ecotoxicity results corroborated this classification thus revealing differences in space and time. The present study includes not only physical, chemical and bacteriological but also ecotoxicological parameters, which broadens new perspectives in river water characterization. Moreover, the application of PCA and CA is very useful to optimize water quality monitoring networks, defining the minimum number of sites and their location. Thus, these tools can support appropriate management decisions.

Seroprevalência de cólera em área endémica : estudo

Ao longo da história, a cólera tem assolado populações sob a forma de epidemias e pandemias com elevada morbimortalidade, que condicionam o desenvolvimento das regiões atingidas (120.000 óbitos estimados por ano a nível mundial). Em 2001, 94% (173.359 casos) dos casos de cólera foram notificados no continente africano (OMS). A cidade da Beira é considerada área de endemo-epidemicidade de cólera. Na cidade da Beira foi realizado um estudo de seroprevalência de cólera (serogrupo O1), em período inter-epidémico, através do doseamento de anticorpos vibriocida, numa amostra de conveniência de 136 indivíduos adultos sem história de vacinação prévia contra a cólera. Obteve-se uma seroprevalência de 2,2%, que não pode ser extrapolada para a população em geral. Ambas as estirpes do serogrupo O1 (Inaba e Ogawa) foram identificadas. A metodologia utilizada é exequível em regiões com suporte laboratorial básico e pode ter interesse como ferramenta de vigilância epidemiológica da cólera na cidade da Beira, dado que a seroprevalência em anticorpos vibriocida traduz a imunidade de grupo da população. A monitorização da seroprevalência pode contribuir para orientar as estratégias de intervenção no sentido do controlo da cólera, nomeadamente na implementação de uma campanha de vacinação. De facto, tendo em conta o impacto da cólera na população e as limitações da estratégia existente, urge equacionar de forma objectiva o papel da vacinação oral na estratégia de controlo da cólera na cidade da Beira.

Vibrios among patients of good socioeconomic conditions during the cholera epidemic in Recife, Brazil

Between March and July, 1992, we screened for Vibrio all fecal samples submitted for bacteriologic diagnosis at a private clinical laboratory in Recife. Of 1435 cultures examined only 1 (0.07%) was positive for V.cholerae 01, biovar Eltor, serovar Inaba, but 17 (1.2%) yielded non-cholera Vibrio (V.cholerae non-01; V.fluvialis; V.furnissii, V.parahaemolyticus and Vibrio spp). Thus, V.cholerae 01, differently of other enteropathogenic vibrios, spared individuals of good socioeconomic conditions even during the cholera epidemic, which made hundreds of victims in the neighboring slums.

Species and serovars of enteropathogenic agents associated with acute diarrheal disease in Rosario, Argentina

We report the most frequent species and serovars of enteropathogenic organisms in Rosario from 1985 to 1993. Enteropathogenic Escherichia coli was the most prevalent agent affecting 144/570 (25.2%) children; 0111 represented 41.8%, 055: 13.6%, 0119: 12.7%. Among enterotoxigenic E. coli (ETEC) the most frequent were ETEC-ST 0128:H21 and 0153:H45. Shigella spp were isolated in 8.8%; S.flexneri: 7%, principally type 2 (59.5%); S. sonnei: 1.6%, and S. dysenteriae type 2: 0.2%. Campylobacter spp were found in 6.1% of patients; C.jejuni: 4.6%; C. coli: 1.4% and C. lari: 0.2%; except groups 0 13,50 and 0 4 (2 cases each), no predominant serogroups were found. Salmonella was isolated in 2.8% of cases, being the predominant serovar S. typhimurium until 1986, but a dramatically increase of cases due to S. enteritidis was observed since 1987. There was 1.9% of Aeromonas spp and 2 cases due to Vibrio cholerae non 0-1. No Yersinia was found. In patients with gastroenteritis due to Shigella, Campylobacter, Salmonella, or EPEC as the unique pathogen, leukocytes were observed in the faeces in 70%, 50%, 20%, and 10% of cases respectively.

Antibacterial effect (in vitro) of Moringa oleifera and Annona muricata against Gram positive and Gram negative bacteria

Antibacterial effects of aqueous and ethanolic extracts of seeds of moringa (Moringa oleifera) and pods of soursop (Annona muricata) in the concentration of 1:5 and 1:10 in volumes 50, 100, 150 and 200 µL were examined against Staphylococcus aureus, Vibrio cholerae, Escherichia coli (isolated from the organism and the aquatic environment) and Salmonella Enteritidis. Antibacterial activity (inhibition halo > 13 mm) against S. aureus, V. cholerae and E. coli isolated from the whiteleg shrimp, Litopenaeus vannmaei, was detected in aqueous and ethanolic extracts of moringa. E. coli isolated from tilapiafish, Oreochromis niloticus, was sensitive to the ethanolic extract of moringa. The aqueous extracts of soursop showed an antibacterial effect against S. aureus and V. cholerae, but the antibacterial activity by the ethanol extracts of this plant was not demonstrated.

Caracterização das águas residuais produzidas no campus universitário da FCT/UNL

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, para obtenção do Grau de Mestre em Engenharia do Ambiente, Perfil de Engenharia Sanitária

Envolvimento de Aeromonas em surto de doença diarréica aguda em São Bento do Una, Pernambuco

No primeiro semestre de 2004, ocorreu um surto de diarréia em São Bento do Una, Pernambuco, registrando-se 2.170 casos. Nas 582 coproculturas realizadas, 145 (25%) revelaram um enteropatógeno bacteriano, destacando 114 casos (19,5%) com a participação de Aeromonas, representadas por Aeromonas caviae (57/9,8%), Aeromonas veronii biovar sobria (23/3,9%), Aeromonas veronii biovar veronii (15/2,6%) e outras espécies (19/3,2%). Nos 31 episódios restantes (5,3%), foram detectados: V. cholerae O1 Ogawa toxigênico (18/3,1%), Salmonella spp (8/1,4%), Shigella spp (3/0,5%) e Vibrio cholerae não O1/não O139 (2/0,3%).

Significância de anticorpos vibriocidas circulantes em área pós-epidêmica de diarréia, São Bento do Una, Estado de Pernambuco

Verificou-se o nível de anticorpos vibriocidas em 41 indivíduos adultos, sem história passada ou presente de diarréia por Vibrio cholerae O1, residentes no município de São Bento do Una, Pernambuco. Nessa localidade ocorreu no início de 2004 um surto de diarréia, com múltiplos agentes bacterianos envolvidos, incluindo o vibrião colérico. Foi empregado o teste da microtitulação de anticorpos séricos vibriocidas, anti-Ogawa e anti-Inaba, considerando-se como indicativo de infecção por Vibrio cholerae O1, os títulos vibriocidas > 1:640. A freqüência dos reagentes foi de 36 (87,8%) para o sorovar Ogawa, o que evidencia a possível circulação do vibrião colérico, durante e/ou após a epidemia de diarréia.

Development of duplex-PCR for identification of Aeromonas species

Introduction The number of reports of intestinal infections caused by Aeromonas spp. has increased significantly in recent years. In most clinical laboratories, identification of these bacteria is carried out by general phenotypic tests that sometimes do not accurately differentiate Aeromonas and Vibrio. Methods A duplex-polymerase chain reaction (PCR) was developed directed to 2 targets identifying Aeromonas spp. pathogenic to humans. Results The duplex-PCR results were reproducible and specific for Aeromonas spp. pathogenic to humans. Conclusions This method will allow differentiation between Vibrio and Aeromonas spp. in patients with in cholera-like symptoms and can also be used in water quality monitoring.

Estudos higiênicos sôbre os crustáceos e moluscos da Baía de Guanabara (Rio de Janeiro)

Revisão da literatura médica sôbre higiene de crustáceos e moluscos marinhos. Intoxicações por elementos extranhos às carnes de crustáceos e moluscos: por sais de cobre, vegetais tóxicos; estranho e chumbo nas conservas de crustáceos; botulismo. Putrefação de ostras e doenças de ostras provocadas por cogumelos; crustáceos e moluscos guardados em geladeiras bolorentas. Lista das espécies de moluscos comestíveis da Bahia de Guanabara. Lista das espécies de crustáceos comestíveis da Bahia de Guanabara. Veiculação de micro-organismos patogênicos ao homem por intermédio das carnes de crustáceos e de moluscos: veiculação do vibrião colérico, dos bacilos tíficos e paratíficos e de germes do grupo coli e do gênero Proteus. Vitalidade dos bacilos tíficos nas ostras. Listas dos moluscos veiculadores dos agentes causadores das febres tíficas e paratíficas. Conceitos antigos e modernos sõbre intoxicações por crustáceos; partidas de crustáceos salubres ou não conforme o local de venda. Estudos experimentais sôbre a "talassina" princípio tóxico existente em alguns crustáceos. "Mitilotoxina", intoxicações por mexilhões e outros acidentes incriminados aos moluscos. Enterotoxina estavfilocócica em ostras. Métodos de determinação da salubridade dos moluscos; verificações nas ostras brasileiras. Depuração dos crustáceos pelas soluções cloradas. Estabulação de caranguejos denominados vulgarmente de "guaiamus" e "ussás".

Evolutionary Control of Infectious Disease: Prospects for Vectorborne and Waterborne Pathogens

Evolutionary theory may contribute to practical solutions for control of disease by identifying interventions that may cause pathogens to evolve to reduced virulence. Theory predicts, for example, that pathogens transmitted by water or arthropod vectors should evolve to relatively high levels of virulence because such pathogens can gain the evolutionary benefits of relatively high levels of host exploitation while paying little price from host illness. The entrance of Vibrio cholerae into South America in 1991 has generated a natural experiment that allows testing of this idea by determining whether geographic and temporal variations in toxigenicity correspond to variation in the potential for waterborne transmission. Preliminary studies show such correspondences: toxigenicity is negatively associated with access to uncontaminated water in Brazil; and in Chile, where the potential for waterborne transmission is particularly low, toxigenicity of strains declined between 1991 and 1998. In theory vector-proofing of houses should be similarly associated with benignity of vectorborne pathogens, such as the agents of dengue, malaria, and Chagas' disease. These preliminary studies draw attention to the need for definitive prospective experiments to determine whether interventions such as provisioning of uncontaminated water and vector-proofing of houses cause evolutionary reductions in virulence

Diversity of Vibrionaceae bacteria isolated from the haemolymph of the spider crab Maja brachydactyla

Aims: The aim of this study was to characterise and identify vibrios isolated from the haemolymph of apparently healthy adult spider crabs (Maja brachydactyla) wild-caught in the Spanish localities of Galician coast and in the Canary Islands and also from captive animals held at IRTA’s facilities in the Ebro Delta of Catalonia, north-west Spanish Mediterranean coast. Methods and Results: A total of 277 bacterial isolates were obtained, and of these, 171 were characterised with rep-PCR, resulting electrophoretic bands were analysed and clusters formed. Identification of representative strains of each cluster was made by sequencing the 16S rRNA. Samples from animals caught in Galicia and captive at IRTA (around 15–18 C) rendered mostly species belonging to the Splendidus clade (72Æ2 and 76Æ6% respectively), commonly found in cold waters (below 20 C). Higher species diversity was found in the haemolymph of the captive animals. In the warmer Canary Islands waters (around 21 C), the diversity of vibrios is dominated by three clades, Harveyi (Vibrio core group, 39Æ3%), Orientalis (23Æ2%) and Splendidus (21Æ4%) with a species diversity that equals that of the colder captive animals. Conclusions: Differences in the vibrios populations were found in the haemolymph extracted from animals collected from the three localities. Potential new species were found, and their description is under way. Significance and Impact of Study: As with other invertebrates, spider crabs also contain a diverse population of vibrios. These findings should help researchers to diagnose when a crab is infected.