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Vibrio vulnificus (Vv) and Vibrio parahaemolyticus (Vp) are water- and foodborne bacteria that can cause several distinct human diseases, collectively called vibriosis. The success of oyster aquaculture is negatively impacted by high Vibrio abundances. Myriad environmental factors affect the distribution of pathogenic Vibrio, including temperature, salinity, eutrophication, extreme weather events, and plankton loads, including harmful algal blooms. In this paper, we synthesize the current understanding of ecological drivers of Vv and Vp and provide a summary of various tools used to enumerate Vv and Vp in a variety of environments and environmental samples. We also highlight the limitations and benefits of each of the measurement tools and propose example alternative tools for more specific enumeration of pathogenic Vv and Vp. Improvement of molecular methods can tighten better predictive models that are potentially important for mitigation in more controlled environments such as aquaculture. [ABSTRACT FROM AUTHOR]

Vibrio vulnificus (Vv) and Vibrio parahaemolyticus (Vp) are water- and foodborne bacteria that can cause several distinct human diseases, collectively called vibriosis. The success of oyster aquaculture is negatively impacted by high Vibrio abundances. Myriad environmental factors affect the distribution of pathogenic Vibrio, including temperature, salinity, eutrophication, extreme weather events, and plankton loads, including harmful algal blooms. In this paper, we synthesize the current understanding of ecological drivers of Vv and Vp and provide a summary of various tools used to enumerate Vv and Vp in a variety of environments and environmental samples. We also highlight the limitations and benefits of each of the measurement tools and propose example alternative tools for more specific enumeration of pathogenic Vv and Vp. Improvement of molecular methods can tighten better predictive models that are potentially important for mitigation in more controlled environments such as aquaculture.

One of the most challenging aspects in culture independent methods for foodborne pathogens' detection is discrimination of dead and live microorganisms. This study aimed to determine the Vibrio parahaemolyticus in seafoods via direct plate counting (DPC) and toxR-based quantitative loop-mediated isothermal amplification (qLAMP) and to discriminate dead and live cells using propidium monoazide (PMA)-qLAMP. A total of 200 samples including finfishes (n= 100) and shrimps (n= 100), representing the Mediterranean, Black and Aegean sea were collected from supermarkets and fish markets of Konya-Turkey. qLAMP was performed in a Real-Time Turbidimeter and the time threshold (tt) values were yielded in 60 minutes. On DPC, the colonies grown on TCBS Agar was further confirmed by conventional PCR based from gyrB1 gene of Vibrio spp. and toxR gene of V. parahaemolyticus. Virulence property of the isolates were determined by tdh based qLAMP. The detection limit of the qLAMP was 1.2×104 CFU/g in artificially contaminated seafoods. DPC, qLAMP and PMA-qLAMP detected V. parahaemolyticus in 8 (4%), 12 (6%) and 12 (6%) samples, respectively. The CFUs of V. parahaemolyticus detected in qLAMP (5.96±0.10 log10 CFU/ml) and PMAqLAMP (4.71±0.13 log10 CFU/ml) were higher than those of DPC (1.99±0.44 log10 CFU/ml) (P<0.05). The mean tt reduction in PMA treated samples was 1.25±0.38 log10 CFU/sample. The tdh gene was not detected in any of the isolates. In conclusion, the toxR-based PMA-qLAMP method could be an alternative to be used more widely and effective assay for the quantification of live V. parahaemolyticus in seafoods. [ABSTRACT FROM AUTHOR]

Analysis of clinical isolates of Vibrio parahaemolyticus from outbreaks in Chile in the cities of Puerto Montt in 2004 and in Antofagasta in 1998 indicated that 23 of 24 isolates from Puerto Montt and 19 of 20 from Antofagasta belonged to the pandemic clonal complex that emerged in Southeast Asia in 1996.

Vibrio vulnificus and V. parahaemolyticus are natural inhabitants of estuarine environments and may be transmitted to humans by ingestion of raw oysters. This study focused on the use of low temperature pasteurization, to reduce these Vibrio spp. to nondetectable levels, thus reducing the risk of infection associated with raw oyster consumption. Artificially inoculated V. vulnificus and V. parahaemolyticus and naturally-contaminated V. vulnificus in live oysters were pasteurized at 50%deg;C for up to 15min. Samples of processed and unprocessed oysters were enumerated for V. vulnificus, V. parahaemolyticus, and aerobic spoilage bacteria for 0-14 days. Low temperature pasteurization was effective in reducing these pathogens from > 100000 to non-detectable levels in less than 10min of processing. Spoilage bacteria were reduced by 2-3 logs, thus increasing the shelf-life for up to 7 days beyond live unprocessed oysters. Vibrio vulnificus in control oysters was reduced by 102 during ice storage alone. Following pasteurization and during a temperature storage abuse study (24h at 22°C), V. vulnificus was not recovered. During this storage period spoilage bacteria exceeded 1 million/g oyster meat. [ABSTRACT FROM AUTHOR]