Relationships between Environmental Factors and Pathogenic Vibrios in the Northern Gulf of Mexico

ABSTRACT Although autochthonous vibrio densities are known to be influenced by water temperature and salinity, little is understood about other environmental factors associated with their abundance and distribution. Densities of culturable Vibrio vulnificus containing vvh (V. vulnificus hemolysin gene) and V. parahaemolyticus containing tlh (thermolabile hemolysin gene, ubiquitous in V. parahaemolyticus), tdh (thermostable direct hemolysin gene, V. parahaemolyticus pathogenicity factor), and trh (tdh-related hemolysin gene, V. parahaemolyticus pathogenicity factor) were measured in coastal waters of Mississippi and Alabama. Over a 19-month sampling period, vibrio densities in water, oysters, and sediment varied significantly with sea surface temperature (SST). On average, tdh-to-tlh ratios were significantly higher than trh-to-tlh ratios in water and oysters but not in sediment. Although tlh densities were lower than vvh densities in water and in oysters, the opposite was true in sediment. Regression analysis indicated that SST had a significant association with vvh and tlh densities in water and oysters, while salinity was significantly related to vibrio densities in the water column. Chlorophyll a levels in the water were correlated significantly with vvh in sediment and oysters and with pathogenic V. parahaemolyticus (tdh and trh) in the water column. Furthermore, turbidity was a significant predictor of V. parahaemolyticus density in all sample types (water, oyster, and sediment), and its role in predicting the risk of V. parahaemolyticus illness may be more important than previously realized. This study identified (i) culturable vibrios in winter sediment samples, (ii) niche-based differences in the abundance of vibrios, and (iii) predictive signatures resulting from correlations between environmental parameters and vibrio densities.

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Effects of Dry Storage and Resubmersion of Oysters on Total Vibrio vulnificus and Total and Pathogenic (tdh+/trh+) Vibrio parahaemolyticus Levels

Journal of Food Protection ◽

10.4315/0362-028x.jfp-15-017 ◽

2015 ◽

Vol 78 (8) ◽

pp. 1574-1580 ◽

Cited By ~ 10

Author(s):

THOMAS P. KINSEY ◽

KERI A. LYDON ◽

JOHN C. BOWERS ◽

JESSICA L. JONES

Keyword(s):

Vibrio Parahaemolyticus ◽

Storage Time ◽

Vibrio Vulnificus ◽

Ambient Air ◽

Most Probable Number ◽

Probable Number ◽

Ambient Temperatures ◽

Dry Storage ◽

Hemolysin Gene ◽

Thermostable Direct Hemolysin

Vibrio vulnificus (Vv) and Vibrio parahaemolyticus (Vp) are the two leading causes of bacterial illnesses associated with raw shellfish consumption. Levels of these pathogens in oysters can increase during routine antifouling aquaculture practices involving dry storage in ambient air conditions. After storage, common practice is to resubmerge these stored oysters to reduce elevated Vv and Vp levels, but evidence proving the effectiveness of this practice is lacking. This study examined the changes in Vv and in total and pathogenic (thermostable direct hemolysin gene and the tdh-related hemolysin gene, tdh+ and trh+) Vp levels in oysters after 5 or 24 h of dry storage (28 to 32°C), followed by resubmersion (27 to 32°C) for 14 days. For each trial, replicate oyster samples were collected at initial harvest, after dry storage, after 7 days, and after 14 days of resubmersion. Oysters not subjected to dry storage were collected and analyzed to determine natural undisturbed vibrio levels (background control). Vibrio levels were measured using a most-probable-number enrichment followed by real-time PCR. After storage, vibrio levels (excluding tdh+ and trh+ Vp during 5-h storage) increased significantly (P < 0.001) from initial levels. After 7 days of resubmersion, Vv and total Vp levels (excluding total Vp in oysters stored for 5 h) were not significantly different (P > 0.1) from levels in background oysters. Vv and total and pathogenic Vp levels were not significantly different (P > 0.1) from levels in background oysters after 14 days of resubmersion, regardless of dry storage time. These data demonstrate that oyster resubmersion after dry storage at elevated ambient temperatures allows vibrio levels to return to those of background control samples. These results can be used to help minimize the risk of Vv and Vp illnesses and to inform the oyster industry on the effectiveness of routine storing and resubmerging of aquaculture oysters.

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Vibrio vulnificus and Vibrio parahaemolyticus in U.S. Retail Shell Oysters: A National Survey from June 1998 to July 1999

Journal of Food Protection ◽

10.4315/0362-028x-65.1.79 ◽

2002 ◽

Vol 65 (1) ◽

pp. 79-87 ◽

Cited By ~ 100

Author(s):

DAVID W. COOK ◽

PAUL O'LEARY ◽

JEFF C. HUNSUCKER ◽

EDNA M. SLOAN ◽

JOHN C. BOWERS ◽

...

Keyword(s):

United States ◽

North Atlantic ◽

Vibrio Parahaemolyticus ◽

Vibrio Vulnificus ◽

Gulf Coast ◽

The United States ◽

Most Probable Number ◽

Probable Number ◽

Hemolysin Gene ◽

Thermostable Direct Hemolysin

From June 1998 to July 1999, 370 lots of oysters in the shell were sampled at 275 different establishments (71%, restaurants or oyster bars; 27%, retail seafood markets; and 2%, wholesale seafood markets) in coastal and inland markets throughout the United States. The oysters were harvested from the Gulf (49%), Pacific (14%), Mid-Atlantic (18%), and North Atlantic (11%) Coasts of the United States and from Canada (8%). Densities of Vibrio vulnificus and Vibrio parahaemolyticus were determined using a modification of the most probable number (MPN) techniques described in the Food and Drug Administration's Bacteriological Analytical Manual. DNA probes and enzyme immunoassay were used to identify suspect isolates and to determine the presence of the thermostable direct hemolysin gene associated with pathogenicity of V. parahaemolyticus. Densities of both V. vulnificus and V. parahaemolyticus in market oysters from all harvest regions followed a seasonal distribution, with highest densities in the summer. Highest densities of both organisms were observed in oysters harvested from the Gulf Coast, where densities often exceeded 10,000 MPN/g. The majority (78%) of lots harvested in the North Atlantic, Pacific, and Canadian Coasts had V. vulnificus densities below the detectable level of 0.2 MPN/g; none exceeded 100 MPN/g. V. parahaemolyticus densities were greater than those of V. vulnificus in lots from these same areas, with some lots exceeding 1,000 MPN/g for V. parahaemolyticus. Some lots from the Mid-Atlantic states exceeded 10,000 MPN/g for both V. vulnificus and V. parahaemolyticus. Overall, there was a significant correlation between V. vulnificus and V. parahaemolyticus densities (r = 0.72, n = 202, P < 0.0001), but neither density correlated with salinity. Storage time significantly affected the V. vulnificus (10% decrease per day) and V. parahaemolyticus (7% decrease per day) densities in market oysters. The thermostable direct hemolysin gene associated with V. parahaemolyticus virulence was detected in 9 of 3,429 (0.3%) V. parahaemolyticus cultures and in 8 of 198 (4.0%) lots of oysters. These data can be used to estimate the exposure of raw oyster consumers to V. vulnificus and V. parahaemolyticus.

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Ecology of Vibrio parahaemolyticus and Vibrio vulnificus in the Coastal and Estuarine Waters of Louisiana, Maryland, Mississippi, and Washington (United States)

Applied and Environmental Microbiology ◽

10.1128/aem.01296-12 ◽

2012 ◽

Vol 78 (20) ◽

pp. 7249-7257 ◽

Cited By ~ 101

Author(s):

Crystal N. Johnson ◽

John C. Bowers ◽

Kimberly J. Griffitt ◽

Vanessa Molina ◽

Rachel W. Clostio ◽

...

Keyword(s):

United States ◽

Organic Carbon ◽

Dissolved Organic Carbon ◽

Vibrio Parahaemolyticus ◽

Vibrio Vulnificus ◽

Environmental Parameters ◽

The United States ◽

Sea Surface ◽

Content Type ◽

Thermostable Direct Hemolysin

ABSTRACTVibrio parahaemolyticusandVibrio vulnificus, which are native to estuaries globally, are agents of seafood-borne or wound infections, both potentially fatal. Like all vibrios autochthonous to coastal regions, their abundance varies with changes in environmental parameters. Sea surface temperature (SST), sea surface height (SSH), and chlorophyll have been shown to be predictors of zooplankton and thus factors linked to vibrio populations. The contribution of salinity, conductivity, turbidity, and dissolved organic carbon to the incidence and distribution ofVibriospp. has also been reported. Here, a multicoastal, 21-month study was conducted to determine relationships between environmental parameters andV. parahaemolyticusandV. vulnificuspopulations in water, oysters, and sediment in three coastal areas of the United States. Because ecologically unique sites were included in the study, it was possible to analyze individual parameters over wide ranges. Molecular methods were used to detect genes for thermolabile hemolysin (tlh), thermostable direct hemolysin (tdh), andtdh-related hemolysin (trh) as indicators ofV. parahaemolyticusand the hemolysin genevvhAforV. vulnificus. SST and suspended particulate matter were found to be strong predictors of total and potentially pathogenicV. parahaemolyticusandV. vulnificus. Other predictors included chlorophylla, salinity, and dissolved organic carbon. For the ecologically unique sites included in the study, SST was confirmed as an effective predictor of annual variation in vibrio abundance, with other parameters explaining a portion of the variation not attributable to SST.

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Predicting the Presence of Leptospires in Rodents from Environmental Indicators Opens Up Opportunities for Environmental Monitoring of Human Leptospirosis

Remote Sensing ◽

10.3390/rs13020325 ◽

2021 ◽

Vol 13 (2) ◽

pp. 325

Author(s):

Leon Biscornet ◽

Christophe Révillion ◽

Sylvaine Jégo ◽

Erwan Lagadec ◽

Yann Gomard ◽

...

Keyword(s):

Infectious Disease ◽

Environmental Factors ◽

Control Strategies ◽

Sampling Site ◽

Rattus Rattus ◽

Environmental Parameters ◽

Environmental Indicators ◽

Small Island ◽

Urban Landscapes ◽

Infection Prevalence

Leptospirosis, an environmental infectious disease of bacterial origin, is the infectious disease with the highest associated mortality in Seychelles. In small island territories, the occurrence of the disease is spatially heterogeneous and a better understanding of the environmental factors that contribute to the presence of the bacteria would help implement targeted control. The present study aimed at identifying the main environmental parameters correlated with animal reservoirs distribution and Leptospira infection in order to delineate habitats with highest prevalence. We used a previously published dataset produced from a large collection of rodents trapped during the dry and wet seasons in most habitats of Mahé, the main island of Seychelles. A land use/land cover analysis was realized in order to describe the various environments using SPOT-5 images by remote sensing (object-based image analysis). At each sampling site, landscape indices were calculated and combined with other geographical parameters together with rainfall records to be used in a multivariate statistical analysis. Several environmental factors were found to be associated with the carriage of leptospires in Rattus rattus and Rattus norvegicus, namely low elevations, fragmented landscapes, the proximity of urbanized areas, an increased distance from forests and, above all, increased precipitation in the three months preceding trapping. The analysis indicated that Leptospira renal carriage could be predicted using the species identification and a description of landscape fragmentation and rainfall, with infection prevalence being positively correlated with these two environmental variables. This model may help decision makers in implementing policies affecting urban landscapes and/or in balancing conservation efforts when designing pest control strategies that should also aim at reducing human contact with Leptospira-laden rats while limiting their impact on the autochthonous fauna.

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Risk and Environmental Factors Associated with the Presence of Canine Parvovirus Type 2 in Diarrheic Dogs from Thessaly, Central Greece

Pathogens ◽

10.3390/pathogens10050590 ◽

2021 ◽

Vol 10 (5) ◽

pp. 590

Author(s):

Maria Kantere ◽

Labrini V. Athanasiou ◽

Alexios Giannakopoulos ◽

Vassilis Skampardonis ◽

Marina Sofia ◽

...

Keyword(s):

Environmental Factors ◽

Clinical Symptoms ◽

Gastrointestinal Disease ◽

Environmental Parameters ◽

Canine Parvovirus ◽

Geographical Information ◽

Factors Associated ◽

Working Dogs ◽

Canine Parvovirus Type 2

Canine parvovirus type 2 (CPV-2) primarily infects dogs, which are the main host reservoir, causing severe gastrointestinal disease associated with immunosuppression. The present study was conducted in Thessaly, Greece and aimed to identify risk and environmental factors associated with CPV-2 infection in diarrheic dogs. Fecal samples were collected from 116 dogs presenting diarrhea and were tested by polymerase chain reaction (PCR) for the presence of CPV-2 DNA. Supplementary data regarding clinical symptoms, individual features, management factors and medical history were also gathered for each animal during clinical evaluation. Sixty-eight diarrheic dogs were found to be positive for the virus DNA in their feces. Statistical analysis revealed that CPV-2 DNA was less likely to be detected in senior dogs, while working dogs, namely hounds and shepherds, had higher odds to be positive for the virus. Livestock density and land uses, specifically the categories of discontinuous urban fabric and of human population density, were identified as significant environmental parameters associated with CPV-2 infection by using Geographical Information System (GIS) together with the Ecological Niche Model (ENM). This is the first description of the environmental variables associated with the presence of CPV-2 DNA in dogs’ feces in Greece.

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The impact of environmental variables on the spread of COVID-19 in the Republic of Korea

Scientific Reports ◽

10.1038/s41598-021-85493-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yong Kwan Lim ◽

Oh Joo Kweon ◽

Hye Ryoun Kim ◽

Tae-Hyoung Kim ◽

Mi-Kyung Lee

Keyword(s):

Environmental Factors ◽

Virus Disease ◽

Environmental Parameters ◽

Environmental Data ◽

Republic Of Korea ◽

Metropolitan Region ◽

Health Concern ◽

Ozone Level ◽

The Republic ◽

The Impact

AbstractCorona virus disease 2019 (COVID-19) has been declared a global pandemic and is a major public health concern worldwide. In this study, we aimed to determine the role of environmental factors, such as climate and air pollutants, in the transmission of COVID-19 in the Republic of Korea. We collected epidemiological and environmental data from two regions of the Republic of Korea, namely Seoul metropolitan region (SMR) and Daegu-Gyeongbuk region (DGR) from February 2020 to July 2020. The data was then analyzed to identify correlations between each environmental factor with confirmed daily COVID-19 cases. Among the various environmental parameters, the duration of sunshine and ozone level were found to positively correlate with COVID-19 cases in both regions. However, the association of temperature variables with COVID-19 transmission revealed contradictory results when comparing the data from SMR and DGR. Moreover, statistical bias may have arisen due to an extensive epidemiological investigation and altered socio-behaviors that occurred in response to a COVID-19 outbreak. Nevertheless, our results suggest that various environmental factors may play a role in COVID-19 transmission.

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Effects of Temperature and Salinity on Vibrio vulnificus Population Dynamics as Assessed by Quantitative PCR

Applied and Environmental Microbiology ◽

10.1128/aem.70.9.5469-5476.2004 ◽

2004 ◽

Vol 70 (9) ◽

pp. 5469-5476 ◽

Cited By ~ 115

Author(s):

Mark A. Randa ◽

Martin F. Polz ◽

Eelin Lim

Keyword(s):

Population Dynamics ◽

Water Temperature ◽

Water Column ◽

Quantitative Pcr ◽

Vibrio Vulnificus ◽

Most Probable Number ◽

Salinity Regime ◽

Optimal Salinity ◽

Probable Number ◽

Barnegat Bay

ABSTRACT The abundance of Vibrio vulnificus in coastal environments has been linked to water temperature, while its relationship to salinity is less clear. We have developed a culture-independent, most-probable-number quantitative PCR approach to examine V. vulnificus population dynamics in Barnegat Bay, N.J. Based on the combined analysis of our results from Barnegat Bay and from the literature, the present data show that (i) V. vulnificus population dynamics are strongly correlated to water temperature and (ii) although the general trend is for V. vulnificus abundance to be inversely correlated with salinity, this relationship depends on salinity levels. Irrespective of temperature, high abundances of V. vulnificus are observed at 5 to 10 ppt, which thus appears to be the optimal salinity regime for their survival. At 20 to 25 ppt, V. vulnificus abundances show a positive correlation to salinity. Unsuccessful attempts to resuscitate V. vulnificus, combined with our inability to detect cells during the winter despite an assay adapted to detect viable but nonculturable (VBNC) cells, suggest that the decline and eventual disappearance of V. vulnificus from the water column during the winter months is due primarily to a significant reduction in population size and is not only the consequence of cells entering the VBNC state. These findings are in line with the hypothesis that the sediment serves as a refuge for a subpopulation of V. vulnificus over the winter and weather-driven mixing events during the spring initiate a summer bloom in the water column.

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Floristic study and assessment of the environmental factors governing the distribution of riparian plants in the Zat sub-Basin: Tensift Watershed, Morocco

Journal of Animal & Plant Sciences ◽

10.35759/janmplsci.v45-2.3 ◽

2020 ◽

Vol 45 (2) ◽

pp. 7900-7915

Author(s):

Mostakim Lahcen ◽

Fetnassi Nidal ◽

Ghamizi Mohamed

Keyword(s):

Environmental Factors ◽

Pearson Correlation ◽

Ecological Status ◽

Environmental Parameters ◽

Quality Parameters ◽

Phosphorus Concentration ◽

Factors Affecting ◽

Riparian Plants ◽

Emergent Plants ◽

Significant Difference

Measuring the phytodiversity and determining environmental factors affecting the abundance and distribution of riparian plants of Zat sub-basin in Morocco were carried out in this study. A hypothesis was tested whether there is any statistically significant difference in environmental parameters and plants communities among the Zat River and its tributaries. For this purpose, water quality parameters such as temperature, pH, salinity, electrical conductivity, Dissolved Oxygen, nitrate and phosphorus concentration, and riparian plants diversity were estimated at 17 stations along the Zat River and its tributaries during the periods (2018 and 2019). The Canonical Correspondence Analysis (CCA) and Pearson correlation were preformed to assess the relationship between environmental parameters, and the distribution and abundance of riparian plants inventoried. The presence of 113 species was recorded, distributed between 43 families and 97 genera, 9 of which were floating-leaved, 24 submerged, and 80 emergent plants. The rare and threatened species inventoried were represented by 7 taxa, whereas 6 species are reported as endemic. Raunkiaer classification showed a dominance of therophytes (38.39%) over the other groups. According to CCA, the abiotic parameters (DO, elevation, salinity and nitrate concentration) were statistically significant parameters governing the distribution and abundance of the riparian plants inventoried. The results obtained reveal the state of the riparian vegetation in the Zat subBasin, therefore we can consider them as a reliable component for the assessment of the ecological status of the aquatic environment.

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Dynamic Subspecies Population Structure of Vibrio Cholerae in Dhaka, Bangladesh

10.21203/rs.3.rs-364004/v1 ◽

2021 ◽

Author(s):

Mohammad Islam ◽

Tania Nasreen ◽

Kevin Y. H. Liang ◽

Fatema-Tuz Johura ◽

Paul C. Kirchberger ◽

...

Keyword(s):

Vibrio Cholerae ◽

Temporal Dynamics ◽

Sampling Period ◽

Amplicon Sequencing ◽

Rapid Expansion ◽

Capital City ◽

Dhaka City ◽

Physiochemical Parameters ◽

Subspecies Level ◽

Abundance And Distribution

Abstract Cholera has been endemic to the Ganges delta for centuries. Although the causative agent, Vibrio cholerae, is autochthonous to coastal and brackish water, cholera occurs continually in Dhaka, the inland capital city of Bangladesh which is surrounded by fresh water. Despite the persistence of this problem, little is known about the environmental abundance and distribution of lineages of V. cholerae, the most important being the pandemic generating lineage (PG) consisting mostly of serogroup O1 strains. To understand spatial and temporal dynamics of PG and other lineages belonging to the V. cholerae species in surface water in and around Dhaka city, we used qPCR and high throughput amplicon sequencing. Seven different freshwater sites across Dhaka were investigated for six consecutive months and physiochemical parameters were measured in situ. Total abundance of V. cholerae was found to be relatively stable throughout the six months sampling period, with 2×105 to 4×105 genome copies/L at six sites and around 5 ×105 genome copies/L at the site located in the most densely populated part of Dhaka city. PG O1 V. cholerae was present in high abundance during the entire sampling period and composed between 24-92% of the total V. cholerae population, only showing occasional but sudden reductions in abundance. In instances where PG O1 lost its dominance, other lineages underwent a rapid expansion while the size of the total V. cholerae population remained almost unchanged. Intraspecies richness of V. cholerae was positively correlated to salinity, conductivity and total dissolved solids (TDS), while it was negatively correlated to dissolved oxygen (DO) concentration in water. Interestingly, negative correlation was observed specifically between PG O1 and salinity, even though the changes in this variable were minor (0-0.8 ppt). Observations in this study suggest that at the subspecies level, population composition of naturally occurring V. cholerae can be influenced by fluctuations in environmental factors, which can lead to altered competition dynamics among the lineages.

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