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Full-Text Articles in Immunology and Infectious Disease

Evaluation Of The Safety And Efficacy Of Hand Sanitizer Products Marketed To Children Available During The Covid-19 Pandemic, L.E. Gloekler, E.J. De Gandiaga, N.R. Binczewski, (...), Mark J. La Guardia, Et Al Jan 2022

Evaluation Of The Safety And Efficacy Of Hand Sanitizer Products Marketed To Children Available During The Covid-19 Pandemic, L.E. Gloekler, E.J. De Gandiaga, N.R. Binczewski, (...), Mark J. La Guardia, Et Al

VIMS Articles

Hand sanitizer use in the United States (U.S.) increased after the SARS-CoV-2 outbreak. The U.S. Food and Drug Administration (FDA) released temporary manufacturer guidance, changing impurity level limits for alcohol-based hand sanitizers (ABHSs). Since the guidance took effect, the FDA has recommended against using these hand sanitizers due to concerns over safety, efficacy, and/or risk of incidental ingestion. To address current gaps in exposure characterization, this study describes a survey of ABHSs marketed to children available in the U.S., as defined by several inclusion criteria. A subset of ABHSs (n = 31) were evaluated for ethanol and organic impurities using …


The Importance Of Long-Term Data Collection To Understand The Historical And Evolutionary Ecology Of Marine Diseases: The Eastern Oyster Disease System In The Usa, As A Case Study, Ryan Carnegie Jan 2021

The Importance Of Long-Term Data Collection To Understand The Historical And Evolutionary Ecology Of Marine Diseases: The Eastern Oyster Disease System In The Usa, As A Case Study, Ryan Carnegie

VIMS Articles

The epizootics in eastern oysters, Crassostrea virginica, of haplosporidiosis or “MSX” disease caused by Haplosporidium nelsoni, and perkinsosis or “dermo” disease caused by Perkinsus marinus, were two of the most significant marine disease events of the last century. Haplosporidium nelsoni, a protozoan parasite
native to Asian populations of the Pacific oyster Crassostrea gigas, emerged in Delaware Bay in 1957 and Chesapeake Bay in 1959 (Andrews,1962; Haskin et al., 1966), and in the decades that followed caused major mortality events
from the Mid-Atlantic region of the USA to Atlantic Canada. Perkinsus marinus is a native pathogen, also a protozoan, that had …


Polystyrene Microplastics Reduce Abundance Of Developing B Cells In Rainbow Trout (Oncorhynchus Mykiss) Primary Cultures, Patty Zwollo, Fatima Quddos, Carey Bagdassarian, Meredith Evans Seeley, Robert Hale, Lauren Abderhalden Jan 2021

Polystyrene Microplastics Reduce Abundance Of Developing B Cells In Rainbow Trout (Oncorhynchus Mykiss) Primary Cultures, Patty Zwollo, Fatima Quddos, Carey Bagdassarian, Meredith Evans Seeley, Robert Hale, Lauren Abderhalden

VIMS Articles

Environmental microplastic pollution (including polystyrene, PS) may have detrimental effects on the health of aquatic organisms. Accumulation of PS microplastics has been reported to affect innate immune cells and inflammatory responses in fish. To date, knowledge on effects of microplastics on the antibody response is still very limited. Here, we investigated effects of small (0.8–20 μm) PS microplastics on the abundance of B lineage cells in primary cultures of developing immune cells from the anterior kidney of rainbow trout. Both purchased PS microbeads and PS microparticles generated from consumer products were used as microplastic sources. We first show that rainbow …


First Comparison Of French And Australian Oshv-1 Μvars By Bath Exposure, Ca Burge, Kimberly S. Reece, Ak Dhar, P Kirkland, B Morga, L Dégremont, N Faury, B Whipple, A Macintyre, C Friedman Jan 2020

First Comparison Of French And Australian Oshv-1 Μvars By Bath Exposure, Ca Burge, Kimberly S. Reece, Ak Dhar, P Kirkland, B Morga, L Dégremont, N Faury, B Whipple, A Macintyre, C Friedman

VIMS Articles

Economically devastating mortality events of farmed and wild shellfish due to infectious disease have been reported globally. Currently, one of the most significant disease threats to Pacific oyster Crassostrea gigas culture is the ostreid herpesvirus 1 (OsHV-1), in particular the emerging OsHV-1 microvariant genotypes. OsHV-1 microvariants (OsHV-1 μvars) are spreading globally, and concern is high among growers in areas unaffected by OsHV-1. No study to date has compared the relative virulence among variants. We provide the first challenge study comparing survival of naïve juvenile Pacific oysters exposed to OsHV-1 μvars from Australia (AUS μvar) and France (FRA μvar). Oysters challenged …


Characterization Of Microsporidian Ameson Herrnkindi Sp. Nov. Infecting Caribbean Spiny Lobsters Panulirus Argus, Hamish J. Small, Gd Stentiford, Dc Behringer, Ma Freeman, Nam Atherley, Kimberly S. Reece, Jeffrey D. Shields Oct 2019

Characterization Of Microsporidian Ameson Herrnkindi Sp. Nov. Infecting Caribbean Spiny Lobsters Panulirus Argus, Hamish J. Small, Gd Stentiford, Dc Behringer, Ma Freeman, Nam Atherley, Kimberly S. Reece, Jeffrey D. Shields

VIMS Articles

The Caribbean spiny lobster Panulirus argus supports a large and valuable fishery in the Caribbean Sea. In 2007-2008, a rare microsporidian parasite with spore characteristics typical of the Ameson genus was detected in 2 spiny lobsters from southeast Florida (FL). However, the parasite species was not confirmed by molecular analyses. To address this deficiency, reported here are structural and molecular data on single lobsters displaying comparable ‘cotton-like’ abdominal muscle containing ovoid microsporidian spores found at different locations in FL in 2014 and 2018 and in Saint Kitts and Nevis Islands in 2017. In the lobster from 2014, multiple life stages …


Parasitic Dinoflagellate Hematodinium Perezi Prevalence In Larval And Juvenile Blue Crabs Callinectes Sapidus From Coastal Bays Of Virginia, Hj Small, Jp Huchin-Mian, Ks Reece, Km Pagenkopp Lohan, Mj Butler Iv, Jd Shields Jun 2019

Parasitic Dinoflagellate Hematodinium Perezi Prevalence In Larval And Juvenile Blue Crabs Callinectes Sapidus From Coastal Bays Of Virginia, Hj Small, Jp Huchin-Mian, Ks Reece, Km Pagenkopp Lohan, Mj Butler Iv, Jd Shields

VIMS Articles

The parasitic dinoflagellate Hematodinium perezi infects the American blue crab Callinectes sapidus and other decapods along the Eastern seaboard and Gulf of Mexico coast of the USA. Large juvenile and adult blue crabs experience high mortality during seasonal outbreaks of H. perezi, but less is known about its presence in the early life history stages of this host. We determined the prevalence of H. perezi in megalopae and early benthic juvenile crabs from multiple locations along the Virginia portion of the Delmarva Peninsula. The DNA of H. perezi was not detected in any megalopae collected from several locations within the …


Method For Serial Passage Of Infectious Hematopoietic Necrosis Virus (Ihnv) In Rainbow Trout, Juliette Doumayrou, M. Gray Ryan, Andrew R. Wargo Jan 2019

Method For Serial Passage Of Infectious Hematopoietic Necrosis Virus (Ihnv) In Rainbow Trout, Juliette Doumayrou, M. Gray Ryan, Andrew R. Wargo

VIMS Articles

Transmission is a fundamental component of pathogen fitness. A better understanding of pathogen transmission can greatly improve disease management. In particular, controlled studies of multiple rounds of natural transmission (i.e. serial passage) can provide powerful epidemiological and evolutionary inferences. However, such studies are possible in only a few systems because of the challenges in successfully initiating and maintaining transmission in the laboratory. Here we developed an efficient and reproducible cohabitation method for conducting controlled experiments investigating the effects of serial passage on infectious hematopoietic necrosis virus (IHNV) in rainbow trout. This method was used to investigate the transmission efficiency and …


Rising Temperatures, Molting Phenology, And Epizootic Shell Disease In The American Lobster, Maya Groner, Jeffrey D. Shields, Df Landers, J Swenarton, Jm Hoenig Nov 2018

Rising Temperatures, Molting Phenology, And Epizootic Shell Disease In The American Lobster, Maya Groner, Jeffrey D. Shields, Df Landers, J Swenarton, Jm Hoenig

VIMS Articles

Phenological mismatchmaladaptive changes in phenology resulting from altered timing of environmental cuesis an increasing concern in many ecological systems, yet its effects on disease are poorly characterized. American lobster (Homarus americanus) is declining at its southern geographic limit. Rising seawater temperatures are associated with seasonal outbreaks of epizootic shell disease (ESD), which peaks in prevalence in the fall. We used a 34-year mark-recapture data set to investigate relationships between temperature, molting phenology, and ESD in Long Island Sound, where temperatures are increasing at 0.4 degrees C per decade. Our analyses support the hypothesis that phenological mismatch is linked to the …


Laboratory Studies On The Effect Of Temperature On Epizootic Shell Disease In The American Lobster, Homarus Americanus, Britnee N. Barris, Jeffrey D. Shields, Hamish J. Small, Juan Pablo Huchin-Mian, Patricia O'Leary, Et Al Jul 2018

Laboratory Studies On The Effect Of Temperature On Epizootic Shell Disease In The American Lobster, Homarus Americanus, Britnee N. Barris, Jeffrey D. Shields, Hamish J. Small, Juan Pablo Huchin-Mian, Patricia O'Leary, Et Al

VIMS Articles

Epizootic shell disease (ESD) is a persistent threat to the population of American lobsters, Homarus americanus H. Milne-Edwards, 1837, in Long Island Sound and off southern New England, USA. ESD is caused by a bacterial dysbiosis that occurs in association with increased water temperature and exposure to anthropogenic stressors. Temperature is a leading factor driving the severity and incidence of ESD. Our objective was to quantify disease progression and dynamics in relation to host molting and mortality at three rigorously controlled temperatures (6, 12, and 18 °C) over a 5–6-mo period. Lobsters were photographed at various time points and image …


Bottom-Up Control Of Parasites, David S. Johnson, Richard Heard Oct 2017

Bottom-Up Control Of Parasites, David S. Johnson, Richard Heard

VIMS Articles

Parasitism is a fundamental ecological interaction. Yet we understand relatively little about the ecological role of parasites compared to the role of free-living organisms. Bottom-up theory predicts that resource enhancement will increase the abundance and biomass of free-living organisms. Similarly, parasite abundance and biomass should increase in an ecosystem with resource enhancement. We tested this hypothesis in a landscape-level experiment in which salt marshes (60,000 m2 each) received elevated nutrient concentrations via flooding tidal waters for 11 yr to mimic eutrophication. Nutrient enrichment elevated the densities of the talitrid amphipod, Orchestia grillus, and the density and biomass of its …


Transmission Routes Maintaining A Viral Pathogen Of Steelhead Trout Within A Complex Multi-Host Assemblage, Rachel Breyta, Ilana Brito, Paige Ferguson, Gael Kurath, Kerry Naish, Maureen Purcell, Ar Wargo, Shannon Ladeau Jan 2017

Transmission Routes Maintaining A Viral Pathogen Of Steelhead Trout Within A Complex Multi-Host Assemblage, Rachel Breyta, Ilana Brito, Paige Ferguson, Gael Kurath, Kerry Naish, Maureen Purcell, Ar Wargo, Shannon Ladeau

VIMS Articles

This is the first comprehensive region wide, spatially explicit epidemiologic analysis of surveillance data of the aquatic viral pathogen infectious hematopoietic necrosis virus (IHNV) infecting native salmonid fish. The pathogen has been documented in the freshwater ecosystem of the Pacific Northwest of North America since the 1950s, and the current report describes the disease ecology of IHNV during 2000-2012. Prevalence of IHNV infection in monitored salmonid host cohorts ranged from 8% to 30%, with the highest levels observed in juvenile steelhead trout. The spatial distribution of all IHNV-infected cohorts was concentrated in two sub-regions of the study area, where historic …


Impact Of Anguillicolides Crassus On American Eels (Anguilla Rostrata), Andrew Wargo, Rob Latour, Troy D. Tuckey, Wolfgang K. Vogelbein Oct 2015

Impact Of Anguillicolides Crassus On American Eels (Anguilla Rostrata), Andrew Wargo, Rob Latour, Troy D. Tuckey, Wolfgang K. Vogelbein

Presentations

American eels Anguilla rostrata are infected by an introduced parasitic nematode Anguillicoloides crassus, which can cause extreme necrosis of their swimbladders, yet effects on the eel population are currently unknown. We collected 3 eel life stages (glass, elver, and yellow) and the presence of A. crassus and swimbladder damage in each eel was quantified. The preliminary data show over 60% prevalence and an even higher prevalence of damaged swimbladders.


The Role Of Mycobacteriosis In Elevated Natural Mortality Of Chesapeake Bay Striped Bass: Developing Better Models For Stock Assessment And Management : A Final Report, Wolfgang K. Vogelbein, John Hoenig, David Gauthier, Matthew Smith, Phil Sadler, Howard Kator, Martha Rhodes Aug 2012

The Role Of Mycobacteriosis In Elevated Natural Mortality Of Chesapeake Bay Striped Bass: Developing Better Models For Stock Assessment And Management : A Final Report, Wolfgang K. Vogelbein, John Hoenig, David Gauthier, Matthew Smith, Phil Sadler, Howard Kator, Martha Rhodes

Reports

Mycobacteriosis is a chronic systemic disease of fishes caused by bacteria belonging to the genus Mycobacterium. The disease currently affects striped bass throughout Chesapeake Bay and prevalence is higher than 90% in certain age groups. Two recently described species, M. shottsii and M. pseudoshottsii, are the most common isolates obtained from diseased fish and are considered the primary etiologic agents. Recent indications that natural mortality (M) has become elevated in Chesapeake Bay striped bass and that mycobacteriosis may be the underlying cause, has caused concern among fishermen, fisheries managers and scientists. However, fundamental questions, such as transmission mode, duration of …


Status Of The Major Oyster Diseases In Virginia 2006-2008 A Summary Of The Annual Oyster Disease Monitoring Program, Ryan Carnegie, Eugene M. Burreson Dec 2009

Status Of The Major Oyster Diseases In Virginia 2006-2008 A Summary Of The Annual Oyster Disease Monitoring Program, Ryan Carnegie, Eugene M. Burreson

Reports

Fall Survey sampling revealed P. marinus levels to be generally normal to high in Virginia tributaries. By 2007 P. marinus was present on every oyster reef sampled, and by the end of the 2006-2008 period the parasite was probably causing some mortality throughout Virginia waters. Data for H. nelsoni are still incomplete for 2006/7 because of funding limitations, but in 2008 H. nelsoni was observed at 17 of 31 sampled reefs, a marked expansion in distribution since 2003/4. A significant MSX disease outbreak occurred in the Great Wicomico River in 2008, as a mild winter and a long period of …


Characterization Of A Rediscovered Haplosporidian Parasite From Cultured Penaeus Vannamei, Lm Nunam, Dv Lightner, Cr Pantoja, Na Stokes, Kimberly S. Reece Feb 2007

Characterization Of A Rediscovered Haplosporidian Parasite From Cultured Penaeus Vannamei, Lm Nunam, Dv Lightner, Cr Pantoja, Na Stokes, Kimberly S. Reece

VIMS Articles

Mortalities of Penaeus vannamei, cultured in ponds in Belize, Central America, began during the last part of the grow-out cycle during the cold weather months from September 2004 through February 2005. Tissue squashes of infected hepatopancreata and histological examination of infected shrimp revealed that the mortalities might have been caused by an endoparasite. To confirm the diagnosis, DNA was extracted from ethanol preserved hepatopancreata and the small-subunit rRNA gene was sequenced. The 1838 by sequence was novel and phylogenetic analysis placed the P. vannamei parasite within the phylum Haplosporidia as a sister taxon to a clade that includes Bonamia and …


Globally Distributed Mycobacterial Fish Pathogens Produce A Novel Plasmid-Encoded Toxic Macrolide, Mycolactone F, B S. Ranger, E A. Malone, L Mosi, S Adusumilli, R E. Lee, A Coloni, M Rhodes, Plc Small Nov 2006

Globally Distributed Mycobacterial Fish Pathogens Produce A Novel Plasmid-Encoded Toxic Macrolide, Mycolactone F, B S. Ranger, E A. Malone, L Mosi, S Adusumilli, R E. Lee, A Coloni, M Rhodes, Plc Small

VIMS Articles

Mycobacterium ulcerans and Mycobacterium marinum are closely related pathogens which share an aquatic environment. The pathogenesis of these organisms in humans is limited by their inability to grow above 35 degrees C. M. marinum causes systemic disease in fish but produces localized skin infections in humans. M. ulcerans causes Burulli ulcer, a severe human skin lesion. At the molecular level, M. ulcerans is distinguished from M. marinum by the presence of a virulence plasmid which encodes a macrolide toxin, mycolactone, as well as by hundreds of insertion sequences, particularly IS2404. There has been a global increase in reports of fish …


Status Of The Major Oyster Diseases In Virginia 2005 A Summary Of The Annual Monitoring Program, Ryan Carnegie, Eugene M. Burreson Jul 2006

Status Of The Major Oyster Diseases In Virginia 2005 A Summary Of The Annual Monitoring Program, Ryan Carnegie, Eugene M. Burreson

Reports

More normal riverflows and salinities returned in 2005 after two very wet years. Temperatures were somewhat colder than normal during the winter, and warmer during the summer. The physical environment was generally more favorable for parasite activity, and thus brought a slight increase in prevalence and intensity of the oyster diseases caused by Perkinsus marinus (Dermo) and Haplosporidium nelsoni (MSX). Among quarterly James River Survey sites, maximum annual P. marinus prevalences returned to levels typical of the mid- 1990s, before the years of drought. P. marinus prevalence reached 92% at Wreck Shoal, 56% at Point of Shoal, 68% at Horsehead …


B Cell Heterogeneity In The Teleost Kidney: Evidence For A Maturation Gradient From Anterior To Posterior Kidney, Patty Zwollo, Suzanne Cole, Erin Bromage, Stephen Kaattari Jun 2005

B Cell Heterogeneity In The Teleost Kidney: Evidence For A Maturation Gradient From Anterior To Posterior Kidney, Patty Zwollo, Suzanne Cole, Erin Bromage, Stephen Kaattari

VIMS Articles

The fish immune system is quite different from the mammalian system because the anterior kidney forms the main site for hematopoiesis in this species. Using transcription factor-specific Abs derived from the murine system, together with anti-trout Ig Abs and Percoll gradient separation, we analyzed B cells from trout kidney sections and compared them to those from spleen and blood. For this study, immune cells were separated by Percoll gradients, and the resulting subpopulations were defined based on expression of B cell-specific transcription factors Pax-5 and B lymphocyte-induced maturation protein-1, as well as proliferative and Ig-secreting properties. Comparison of kidney, blood, …


Status Of The Major Oyster Diseases In Virginia 2004 A Summary Of The Annual Monitoring Program, Ryan Carnegie, Eugene M. Burreson Mar 2005

Status Of The Major Oyster Diseases In Virginia 2004 A Summary Of The Annual Monitoring Program, Ryan Carnegie, Eugene M. Burreson

Reports

2004 was the second very wet year in a row. While rainfall and streamflows were normal in winter and early spring, and just slightly above average during the summer, the fall of 2004 was nearly as wet as the year before. Salinities were again depressed throughout the lower Bay. Water temperatures were below normal during the winter, but typical otherwise. Low salinities and, in the winter, temperatures brought continued abatement in the oyster diseases caused by Perkinsus marinus (Dermo) and Haplosporidium nelsoni (MSX). Among quarterly James River Survey sites, maximum annual P. marinus prevalences were the lowest they had been …


Status Of The Major Oyster Diseases In Virginia 2003 A Summary Of The Annual Monitoring Program, Ryan Carnegie, Lisa M. Ragone Calvo, Eugene M. Burreson Jun 2004

Status Of The Major Oyster Diseases In Virginia 2003 A Summary Of The Annual Monitoring Program, Ryan Carnegie, Lisa M. Ragone Calvo, Eugene M. Burreson

Reports

Low temperatures and salinities brought abatement in the oyster diseases caused by Perkinsus marinus (Dermo) and Haplosporidium nelsoni (MSX) for the first time since 1998. In the James River, P. marinus prevalences were the lowest they had been since 1998. In summer and fall, when P. marinus is normally most prevalent, it was found in a maximum of 72% of oysters at Wreck Shoal and in less than half the oysters at Horsehead Rock and Point of Shoals. Advanced infections were very rare. Haplosporidium nelsoni had disappeared completely from quarterly James River samples by July


Plasmablast And Plasma Cell Production And Distribution In Trout Immune Tissues, E S. Bromage, I M. Kaattari, P Zwollo, S L. Kaattari Jan 2004

Plasmablast And Plasma Cell Production And Distribution In Trout Immune Tissues, E S. Bromage, I M. Kaattari, P Zwollo, S L. Kaattari

VIMS Articles

These studies describe the in vitro and ex vivo generation of plasmablasts and plasma cells in trout (Oncorhynchus mykiss) peripheral blood and splenic and anterior kidney tissues. Cells were derived either from naive trout and cultured with the polyclonal activator, Escherichia coli LPS, or from trout that had been immunized with trinitrophenyl-keyhole limpet hemocyanin. Hydroxyurea was used to resolve populations of replicating (plasmablast) and nonreplicating (plasma cell) Ab-secreting cells (ASC). Complete inhibition of Ig secretion was only observed within the PBL. Both anterior kidney and splenic lymphocytes possessed a subset of ASCs that were hydroxyurea resistant. Thus, in vitro production …


Status Of The Major Oyster Diseases In Virginia 2002 A Summary Of The Annual Monitoring Program, Lisa M. Ragone Calvo, Eugene M. Burreson Mar 2003

Status Of The Major Oyster Diseases In Virginia 2002 A Summary Of The Annual Monitoring Program, Lisa M. Ragone Calvo, Eugene M. Burreson

Reports

Samples collected monthly from the upper James River sites from January through May showed a decline in P. marinus prevalence during the 4 winter and spring following a typical annual pattern; however, annual minimums were atypically high, particularly at Point of Shoals and Wreck Shoal (12-44%). Unusually high salinity conditions and warm winter temperatures promoted high overwintering survival of the pathogen and an early onset of the disease in the summer months. Perkinsus marinus prevalence increased to 100% at all four of the upper river stations and record high infection intensities were observed at Deepwater Shoal and Horsehead Rock. It …


Are Pfiesteria Species Toxicogenic? Evidence Against Production Of Ichthyotoxins By Pfiesteria Shumwayae, Jp Berry, Kimberly S. Reece, Ks Rein, Dg Baden, Lw Haas, Wl Ribeiro, Jeffrey D. Shields, Rv Snyder, Wolfgang K. Vogelbein, Re Gawley Aug 2002

Are Pfiesteria Species Toxicogenic? Evidence Against Production Of Ichthyotoxins By Pfiesteria Shumwayae, Jp Berry, Kimberly S. Reece, Ks Rein, Dg Baden, Lw Haas, Wl Ribeiro, Jeffrey D. Shields, Rv Snyder, Wolfgang K. Vogelbein, Re Gawley

VIMS Articles

The estuarine genus Pfiesteria has received considerable attention since it was first identified and proposed to be the causative agent of fish kills along the mid-Atlantic coast in 1992. The presumption has been that the mechanism of fish death is by release of one or more toxins by the dinoflagellate. In this report, we challenge the notion that Pfiesteria species produce ichthyotoxins. Specifically, we show that (i) simple centrifugation, with and without ultrasonication, is sufficient to "detoxify" water of actively fish-killing cultures of Pfiesteria shumwayae, (ii) organic extracts of lyophilized cultures are not toxic to fish, (fit) degenerate primers that …


Status Of The Major Oyster Diseases In Virginia 2001 A Summary Of The Annual Monitoring Program, Lisa M. Ragone Calvo, Eugene M. Burreson Feb 2002

Status Of The Major Oyster Diseases In Virginia 2001 A Summary Of The Annual Monitoring Program, Lisa M. Ragone Calvo, Eugene M. Burreson

Reports

Thirty-nine oyster populations were surveyed for disease in fall 2001. Perkinsus marinus was found in all areas sampled and prevalence exceeded 90% at all but 5 sample locations. In the James River P. marinus prevalence ranged from 88-100% at Deepwater Shoal, Horsehead Rock, Point of Shoals, Wreck Shoal, Mulberry Point, Swash, Long Shoal, and Dry Shoal. A lower prevalence was observed down river at Thomas Rock, 72%, and at Nansemond Ridge, 12%. The extremely low prevalence at Nansemond Ridge is likely age and density related; the oyster population was primarily comprised of spat; few small to market oysters were present …


Status Of The Major Oyster Diseases In Virginia 2000 A Summary Of The Annual Monitoring Program, Lisa M. Ragone Calvo, Eugene M. Burreson May 2001

Status Of The Major Oyster Diseases In Virginia 2000 A Summary Of The Annual Monitoring Program, Lisa M. Ragone Calvo, Eugene M. Burreson

Reports

As a consequence of the relatively warm temperatures, high salinities, and high oyster parasite abundances in the fall of 1999, both P. marinus and H. nelsoni were widely distributed throughout oyster populations in Virginia in 2000. Fortunately, however, we did not see severe epizootics of the diseases as observed in some areas in 1999.


Reduction In Dna Binding Activity Of The Transcription Factor Pax-5a In B Lymphocytes Of Aged Mice, J Anspach, G Poulsen, I Kaattari, R Pollock, P Zwollo Jan 2001

Reduction In Dna Binding Activity Of The Transcription Factor Pax-5a In B Lymphocytes Of Aged Mice, J Anspach, G Poulsen, I Kaattari, R Pollock, P Zwollo

VIMS Articles

Aging has been associated with intrinsic changes of the humoral immune response, which may lead to an increased occurrence of autoimmune disorders and pathogenic susceptibility. The transcription factor Pax-5 is a key regulator of B cell development. Pax-5a/B cell-specific activator protein and an alternatively spliced isoform, Pax-Sd, may have opposing functions in transcriptional regulation due to the lack of a transactivation domain in Pax-Sd. To study B cell-specific changes that occur during the aging process, we investigated expression patterns of Pax-Sa and Sd in mature B cells of young and aged mice. RNase protection assays showed a similar transcriptional pattern …


Status Of The Major Oyster Diseases In Virginia 1999 A Summary Of The Annual Monitoring Program, Lisa M. Ragone Calvo, Eugene M. Burreson Feb 2000

Status Of The Major Oyster Diseases In Virginia 1999 A Summary Of The Annual Monitoring Program, Lisa M. Ragone Calvo, Eugene M. Burreson

Reports

As a consequence of the relatively warm temperatures and high salinities severe epizootics of both H. nelsoni and P. marinus occurred in most tributaries in VA. In the upper James River, VA prevalences and intensities of P. marinus were the highest on record. The proportion of advanced infections (moderate and heavy intensity) in October was 60% at Wreck Shoal and 48% at Horsehead Rock suggesting that significant oyster mortalities occurred in these areas. 1 Record high levels of P. marinus were also observed in Virginia's other major tributaries. Of the 39 bay oyster populations surveyed in the fall, P. marinus …


Mortality And Hematology Of Blue Crabs, Callinectes Sapidus, Experimentally Infected With The Parasitic Dinoflagellate Hematodinium Perezi, Jeffrey D. Shields, Christopher M. Squyars Jan 2000

Mortality And Hematology Of Blue Crabs, Callinectes Sapidus, Experimentally Infected With The Parasitic Dinoflagellate Hematodinium Perezi, Jeffrey D. Shields, Christopher M. Squyars

VIMS Articles

On the eastern seaboard of the United States, populations of the blue crab, Callinectes sapidus, experi-ence recurring outbreaks of a parasitic dinoflagellate, Hematodinium perezi. Epizootics fulminate in summer and autumn causing mortalities in high-salinity embayments and estuaries. In laboratory studies, we experimentally investigated host mortality due to the disease, assessed differential hemato-logical changes in infected crabs, and examined proliferation of the parasite.


Status Of The Major Oyster Diseases In Virginia 1998 A Summary Of The Annual Monitoring Program, Lisa M. Ragone Calvo, Eugene M. Burreson Mar 1999

Status Of The Major Oyster Diseases In Virginia 1998 A Summary Of The Annual Monitoring Program, Lisa M. Ragone Calvo, Eugene M. Burreson

Reports

No abstract provided.


Environmental Factors And The Infectious Disease Caused By The Protozoan Parasite, Perkinsus Marinus, In Eastern Oysters (Crassostrea Virginica), Fle Chu Jan 1999

Environmental Factors And The Infectious Disease Caused By The Protozoan Parasite, Perkinsus Marinus, In Eastern Oysters (Crassostrea Virginica), Fle Chu

VIMS Articles

Temperature and salinity are two important factors limiting the distribution and abundance of Perkinsus marinus, a protozoan parasite of Eastern oysters (Crassostrea virginica). Results of laboratory studies ale consistent with field observations and clearly demonstrate that P. marinus susceptibility and disease advancement are positively correlated with temperature, salinity and in situ number of infective cells. Laboratory findings also suggest that environmental degradation may enhance the epizootic, although disease caused by P. marinus in oysters is known to be predominantly exacerbated by elevated temperature and salinity. Oysters cellular defence mechanisms appear ineffective in defence against P. marinus. Also, pollutant esposure caused …