Emerging Pathogens and Infectious Diseases

Research in the Wildlife and Aquatic Veterinary Disease Laboratory (WAVDL)

The Wildlife and Aquatic Veterinary Disease Lab consists of researchers and graduate students with interests in diseases of marine animals. The lab has facilities at both the University of Florida (Gainesville, FL) and the Hubbs-SeaWorld Research Institute (San Diego, CA). We work in close collaboration with SeaWorld Adventure Parks, the U.S. Navy Marine Mammal Program, the National Marine Fisheries Service, and the Florida Fish and Wildlife Conservation Commission. The two primary areas of interest of our lab are infectious diseases, especially viral diseases, of marine mammals and health and disease studies in sea turtles.

Our lab mainly provides expertise in virus discovery and marine mammal viral disease investigation. Pathogen discovery efforts go beyond the simple cataloguing of these agents. Instead, the veterinary relevance of newly discovered pathogens is explored via extensive disease investigations. We develop the tools needed to assess the clinical signs and severity of diseases that are caused by each agent. Using these data, the impact a virus may have on individuals and populations is then determined. A complete work-up of a pathogen typically includes surveillance of multiple wild and managed marine mammal populations for evidence of and frequency of virus and/or exposure. This information is then used to provide the science needed to generate guidelines for disease outbreak management and prevention strategies. Recent pathogen assessments include, but are not limited to poxviruses of seals, sea lions and dolphins, dolphin parainfluenzavirus type 1, San Miguel sea lion virus, dolphin enterovirus, and herpesviruses of whales and dolphins.

Failure of passive antibody transfer in neonatal bottlenose dolphins makes up a distinct, second research component of our lab. Like many other species, the amount of antibodies that dolphin calves receive via the dam’s colostrum significantly influences the survival of neonate dolphins. Failure to obtain these maternal antibodies is common, especially in stranded orphan calves. Our lab has developed protocols for the purification of intravenous-grade dolphin immunoglobulins (IVIG) for therapeutic use. IVIG supplementation protocols are currently based on empirical evidence. We are working closely with veterinary clinicians of various oceanaria and zoological parks to develop effective, science-based IVIG supplementation protocols for bottlenose dolphin calves.

Our work with sea turtles is multi-faceted and includes investigation of causes of sea turtle strandings, infectious disease studies, and human impact concerns such as fisheries by-catch and watercraft collisions. We work closely with sea turtle programs within the National Marine Fisheries Service, state wildlife agencies, the Sea Turtle Stranding and Salvage Network, and rehabilitators.

Diagnostic Techniques in Aquatic Animal Medicine

The ability to test for and gain information about potential disease agents of aquatic animals often is opportunistic depending on the tests available, a researcher’s interest, or tests that have been developed in other domestic species. It therefore is important to understand the assay and its limitations when interpreting results. This guide provides a review of the basic principles of traditional and novel techniques used by clinical and anatomic pathologists, electron microscopists, microbiologists, and molecular and serologic diagnosticians in aquatic animal medicine. It also reviews the appropriate sampling and handling requirements for each technique. The goal is to increase the overall understanding of the available assays, so that results will be evaluated critically and interpreted correctly. We intend that this guide of diagnostic techniques will help maximize the information gained from each physical exam, phlebotomy, biopsy, and necropsy.

The WAVDL does not provide routine diagnostic services. Please contact Dr. Wellehan or Dr. Stacy for inquires regarding our availability for sample submissions and participation in research projects.

Further information on active research projects can be found on the individual profile pages of WAVDL members.

Lab members:

Thomas Waltzek, MS, DVM, PhD

 

Brian Stacy, DVM, PhD, Dipl ACVP

 

 

 

 

 

James Wellehan, DVM, MS, Dipl ACVM, Dipl ACZM

 

 

 

 

 

 

 

 

 

 

Linda Archer, BSc

 

 

 

 

 Jennifer Keene, MS

 

 

 

 

 

 

 

 

 

 

 

Rebecca Rivera, PhD (San Diego)

 

 

 

 

 

 

 

 

 

 

 

Research in Dr. Carlos H. Romero’s Laboratory on marine mammal viruses

Work in my laboratory aims at isolating and characterizing viruses of marine mammals, with special emphasis on those that affect cetaceans and pinnipeds and adversely impact on their health. We use conventional and molecular assays for these purposes and over the years have been accumulating a significant amount of genetic data on viral members of the Caliciviridae, Herpesviridae, Papillomaviridae, Paramyxoviridae, and Poxviridae.

As very little is known about marine viruses’ genetic diversity and dissemination in their marine ecosystem, research efforts also involve developing improved diagnostic assays for virus detection in natural secretions and excretions and in lesions and tissues from affected marine mammals. Sequencing of full virus genomes or recovery of complete genes in the case of large genomes has allowed for the engineering of recombinant antigens and virus-like particles that are being used in ELISA platforms to study virus spread in the US Pacific and Atlantic coasts as well as in waters of the Gulf of Mexico.

The development of a real-time PCR assay has allowed for the identification of previously unknown gammaherpesviruses in mucosal lesions of captive and free-ranging cetaceans that affect the digestive, genital and respiratory tracts. Our group and other research groups hypothesize that the increase in clinical cases of gammaherpesviruses observed over the last decade may be a consequence of marine habitat degradation and relative immunosuppression of marine mammals. Real-time RT-PCR assays have also been developed for the rapid detection and identification of known and emerging marine vesiviruses of Stellar sea lions from Alaska waters. Furthermore, real-time RT-PCR assays recently developed in our laboratories for the detection of morbilliviruses were successfully used to identify a dolphin morbillivirus associated with mass mortality of striped dolphins in waters of the Mediterranean coast of Spain in 2007. These unique real-time assays allow for the first time for the rapid differential diagnosis of dolphin and porpoise morbillivirus.

Current work focuses on viral surveillance and diagnostics for marine mammals in zoos and aquariums worldwide. Fee for service testing is available for all viral agents mentioned above. For more information please visit Dr. Romero’s profile which contains publication and contact information. 

Research in Dr. Sheppard’s Laboratory

Discovery and investigation of the OIE- reportable shellfish pathogen, Perkinsus olseni, in ornamental reef clams, Tridacna crocea, legally imported from Vietnam into the USA (Sheppard and Phillips, 2008); cross-infection potential for domestic shellfish; implications/sentinel role for ocean health and enhanced escalation of pathogen loads in stressed aquatic ecosystems. For more about this discovery see the article in our News section.

Investigation of brevetoxin-induced DNA damage, mitogenesis, and apoptosis in human lung cancer cell lines, collaborative investigation and development of murine cancer models with UF Cancer Center, and detoxification mechanisms in aquatic molluscs and environmental/evolutionary relevance of toxin metabolism for aquatic invertebrate resistance.

Special interest in aquatic invertebrate pathology; pathologist for endangered Partula sp. snails and aquatic invertebrate TAG.

We generally do not test outside samples but will accept samples on an individual basis if contacted directly.

For more information please visit Dr. Barbara Sheppard’s profile which contains publication and contact information.

Please visit Dr. Lisa Farina’s profile for information on her research work.

 

UF Emerging Pathogens Institute