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negative vibrios were isolated from seawater, sediment, plankton, and animal samples taken from 80 sites from Miami, Fla., to Portland, Maine. Of these, 4.2% were able to ferment lactose. The lactose-positive strains isolated from the various samples correlated positively with pH and turbidity of the water, vibrios in the sediment and oysters, and total bacterial counts in oysters. Negative correlations were obtained for water salinity. Numerical taxonomy was performed on 95 of the lactose-fermenting environmental isolates and 23 reference strains. Five clusters resulted, with the major cluster containing 33 of the environmental isolates and all of the Vibrio vulnificus reference strains. The 33 isolates, which produced an acid reaction in lactose broth within hours of initial inoculation, represented 20% of all lactose-fermenting vibrios studied. These isolates were nearly identical phenotypically to clinical strains of V. vulnificus studied by the Centers for Disease Control, Atlanta, Ga., and by our laboratory, and their identification was confirmed by DNA-DNA hybridization studies. V. vulnificus was isolated from all sample types and from Miami to Cape Cod, Mass., and comparison of the environmental parameters of the eight subsites yielding this species with those of all 80 subsites revealed no significant differences. The majority of the isolates were obtained from animals, with clams providing most (84%) of these. On injection into mice, 82% of the V. vulnificus isolates resulted in death. Members of the remaining four clusters contained strains which differed from V. vulnificus in such phenotypic traits as luminescence and in urease or H2S production. None of the other reference cultures, including nine other Vibrio species, were contained in the remaining clusters, and these isolates could not be identified. Most of these were also lethal for mice. Phenotypic differences, potential pathogenicity, and geographic distribution of the five clusters were examined. It is concluded that V. vulnificus is a ubiquitous organism, both geographically and in a variety of environmental sources, although it occurs in relatively low numbers. The public health significance of this organism and of the other unidentified lactose-fermenting Vibrio species is discussed. Vibrio vulnificus is a lactose-fermenting, opportunistic human pathogen capable of causing death in mice within 2.5 h (3, 19) and in humans within 2 or 3 days (2, 6). Although infections apparently can occur in otherwise healthy individuals (11), human disease typically results from ingestion of contaminated seafood or from infection of a wound, frequently of crab or oyster origin (2). Studies from our laboratory and from case histories suggest that persons with elevated serum iron levels (owing to, e.g., chronic alcoholism, hepatitis, thalassemia major, or hemochromatosis) are especially vulnerable to infection by this organism (2, 27). The organism is able to cause massive damage to the intestinal wall, which probably allows its penetration to the circulator...

Water, sediment, plankton, and animal samples from five coastal sites from North Carolina to Georgia were sampled for their lactose-fermenting vibrio populations. Over 20% of all vibrios tested were sucrose negative and onitrophenyl- ,-D-galactopyranoside (ONPG) positive, suggesting identification as the human pathogen Vibrio vulnificus. These vibrios were isolated from all sample sites and sources (water, sediment, plankton, and animals). Correlations with several of 19 environmental parameters monitored at each site were found for total vibrios. The presence of ONPG-positive, sucrose-negative vibrios was correlated with hydrocarbon levels in the water and, in the case of plankton samples, with salinity. A total of 279 sucrose-negative, ONPG-positive isolates were subjected to numerical taxonomic analysis, which resulted in three major clusters. Cluster I corresponded to and included 11 reference strains of V. vulnificus. Cluster II contained the largest number (133) of isolates, of which the great majority were bioluminescent. Although having a resemblance to V. harveyi, the isolates were ONPG positive and many were H2S positive. Cluster III consisted of strains similar to the group F vibrios (V. fluvialis). Of all of the isolates, 55% were luminescent, of which over 20% were lethal when injected into mice. Problems involved in detecting lactose fermentation among marine vibrios and the potential pathogenicity of these organisms are discussed.

Coastal, benthic communities, such as coral reefs, are at particular risk due to poor water quality caused by hurricanes. In addition to the physical impacts from wave action and storm surge, hurricanes bring significant rainfall resulting in increased runoff from land. Hurricanes Irma and Maria caused record or near-record floods at many locations across Puerto Rico and resulted in major impacts on coastal and benthic ecosystems from heavy rainfall and river discharge. In this study, we use imagery from the moderate resolution Visible Infrared Imaging Radiometer Suite (VIIRS) satellite to quantify the impacts of hurricanes Irma and Maria, which struck Puerto Rico during September 2017, on the water quality of the coastal waters of Puerto Rico using the chlorophyll-a (Chl-a) and the diffuse attenuation coefficient at 490 nm (Kd490) products. The objectives include: (1) quantify the water quality and light attenuation after the hurricanes; (2) compare this event to the climatology of these parameters, and 3) evaluate long-term exposure and exceedances of various coastal areas to low levels of turbidity. The Chl-a inner shelf values increased in 2017 during the months of June (8% above baseline), July (17%), August (5%), September (8%), October (19%), and November (28%) when compared to 2012–2016 baseline data. The values for Chl-a concentration reached and exceeded 0.45 µg/L by August 2017 and persisted above that value until December 2017. The Kd490 inner shelf values for 2017 increased (in percent) for the months of June (4% above baseline), July (9%), August (10%), September (5%), October (12%), and November (7%) when compared to 2012–2016 baseline data. The values of Kd490 in August, September, and December 2017 were the highest seen during 2012–2017. Even with the limitations of spatial resolution and loss of data to cloud cover, the 6-year imagery time-series analysis can provide a useful evaluation of the effects of these two hurricanes on the coastal water quality in Puerto Rico, and quantify the exposure of benthic habitats to higher nutrient and turbidity levels.