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INTRODUCTION Escherichia coli (E. coli) O157 is a well-recognized cause of watery diarrhea, hemorrhagic colitis, and hemolyticuremic syndrome. (1) Reported vehicles for E. coli O157 infection include ground beef, unpasteurized […]

The genus Salmonella has 2 species, bongori and enterica; the latter species is divided into 6 subspecies: enterica (I), salamae (II), arizonae (IIIa), diarizonae (IIIb), houtenae (IV), and indica (VI). [...]

The genus Shewanella is currently composed of more than 50 species that inhabit a range of marine environs and ecosystems. Several members of this genus, including S. oneidensis, have been identified that could potentially play key roles in environmental processes such as bioremediation of toxic elements and heavy metals and serving as microbial fuel cells. In contrast to this beneficial role, shewanellae are increasingly being implicated as human pathogens in persons exposed through occupational or recreational activities to marine niches containing shewanellae. Documented illnesses linked to Shewanella include skin and soft tissue infections, bacteremia, and otitis media. At present, it is unclear exactly how many Shewanella species are truly bona fide human pathogens. Recent advances in the taxonomy and phylogenetic relatedness of members of this genus, however, support the concept that most human infections are caused by a single species, S. algae. Some phylogenetic data further suggest that some current members of the genus are not true Shewanella species sensu stricto. The current review summarizes our present knowledge of the distribution, epidemiology, disease spectrum, and identification of microbial species focusing on a clinical perspective. [ABSTRACT FROM AUTHOR]

Several sub-Saharan African countries, including Zambia, have initiated national voluntary medical male circumcision (MC) programs to reduce HIV incidence. In-depth interviews were conducted with twenty female sex workers (FSWs) in Lusaka to examine their understanding of MC and experiences with circumcised clients. Knowledge of MC was derived primarily through informal sources, with very few FSWs reporting exposure to MC educational campaigns. MC was not widely believed to be protective against HIV, however it was viewed by some as protective against STIs. Three FSWs reported having sex with recently circumcised clients, and most reported that men often used their MC status to try to convince FSWs to forego condoms. Findings suggest that FSWs, already at high risk for HIV infection, may face additional pressure toward higher risk behavior as a result of MC. As MC services are expanded, programs should support FSWs' efforts to protect themselves by providing information about what MC can - and cannot - offer for HIV/STI infection prevention. [ABSTRACT FROM AUTHOR]

Different groups of green-lipped mussels (Perna viridis) were exposed to the same net amount of a genotoxicant mixture of four polycyclic aromatic hydrocarbons ([PAHs]; anthracene, fluoranthene, pyrene, and benzo[a]pyrene) and four organochlorine pesticides ([OCs]; a-hexachlorocyclohexane (HCH), aldrin, dieldrin, and p,p'-DDT) for four weeks under different regimes that simulated various scenarios of fluctuating toxicant levels in the marine environment. Micronucleus (MN) formation in gill cells was studied at the end of each week. Micronucleus frequencies increased with continual addition of genotoxicants, and did not diminish significantly under conditions of either gradually decreasing concentrations or cessation of exposure for one to two weeks, suggesting that the MN response may persist over relatively long exposure periods. An almost two-fold higher mean MN frequency was recorded in a chronic exposure group than in an acute group that had received the same net nominal dose of genotoxicants, indicating that chronic exposure may lead to a greater genotoxic impact than acute exposure. The results suggested that in field studies, MN response should be monitored at multiple time points in order to elucidate the effects of potentially fluctuating toxicant levels. Finally, MN formation was positively correlated with both nominal contaminant levels and tissue levels of the genotoxicants. These findings suggest that MN responses can be a sensitive indicator of exposure to relatively low levels of genotoxicants and that MN response in mussel gill cells can be a stable biomarker of genotoxicity. [ABSTRACT FROM AUTHOR]

Presents a study that identified cases and determined risk factors for an outbreak of Escherichia coli O157: nonmotile infections in children attending a summer day care program in California. Methodology; Results; Discussion.

In this study, a suite of sublethal stress biomarkers were analysed in the sediment-dwelling bivalve, Austrovenus stutchburyi, with a view to using them as pollution monitoring tools. Shellfish were transplanted from a relatively uncontaminated site to four sites in a different harbour with different levels of contaminants in the sediment, where they were exposed in-situ for 2 and 8 weeks. A range of sublethal stress biomarkers were selected on the basis of their potential to provide ecologically relevant information (adenylate energy charge, total adenylate nucleotide pool, glycogen and RNA). Adenylate energy charge was lower at contaminated sites after 2 weeks, but recovered after 8 weeks, whereas total adenylate nucleotide pool was depressed after 8 weeks at these sites. Glycogen and RNA were found to be significantly higher at the uncontaminated site after both 2 and 8 weeks. These data suggest the potential application of biomarkers in coastal pollution monitoring. [ABSTRACT FROM AUTHOR]

Investigates Escherichia coli 0157 and Salmonella infections associated with alfalfa sprouts in California in 1996 to 1998. Indication of outbreaks; Cases of gastrointestinal illness or urinary tract infection; Problems with the way sprouts are produced; Isolation of outbreak strains of Salmonella from sprouts and seeds supplied by sprout growers.

It has been almost 10 years since a major review on the association of Aeromonas with human disease has been published. During that period the number of valid species in the genus has grown to 14, with a new family (Aeromonadaceae) established to house this genus. Despite this explosion in the number of new genomospecies, only five (Aeromonas hydrophila, A. caviae, A. veronii, A. jandaei, and A. schubertii) are currently recognized as human pathogens. New syndromes attributed to this genus include hemolytic uremic syndrome, burn-associated sepsis, and a variety of respiratory tract infections, including epiglottitis. Convincing evidence suggests that some aeromonads do cause gastroenteritis, but it is presently unclear whether many of the strains isolated from feces are involved in diarrheal disease. Many questions regarding this genus remain unanswered. [ABSTRACT FROM PUBLISHER]

The role of the genus Edwardsiella in human illness is reviewed. Of the three recognized species, only Edwardsiella tarda has been demonstrated to be pathogenic for humans. Chief infections associated with this species include bacterial gastroenteritis, wound infections such as cellulitis or gas gangrene associated with trauma to mucosal surfaces, and systemic disease such as septicemia, meningitis, cholecystitis, and osteomyelitis. Risk factors that are associated with E. tarda infections include exposure to aquatic environments or exotic animals (e.g., reptiles or amphibia), preexisting liver disease, conditions leading to iron overload, and dietary habits (e.g., raw fish ingestion). Although studies indicate that this bacterium is susceptible to most commonly prescribed antibiotics, fatal gastrointestinal and extraintestinal infections have been described. [ABSTRACT FROM PUBLISHER]

Vibrio hollisae, one of the more recently described halophilic Vibrio species, is infrequently associated with gastrointestinal disease and only rarely recovered from individuals presenting with gram-negative sepsis. In this report we describe two cases of severe gastrointestinal disease associated with V. hollisae in otherwise healthy individuals. In one of these individuals, severe epigastric pain was apparently associated with signs of pseudoappendicitis, necessitating exploratory surgery. In both individuals, infection was associated with the ingestion of raw shellfish. These cases are discussed in light of previous reports on the epidemiology, pathogenesis, and spectrum of disease caused by this unusual pathogen. [ABSTRACT FROM PUBLISHER]