Cetacean Susceptibility to Dolphin Morbillivirus

Rebecca J. Gast, Biology
Andrea Bogomolni, Biology



Over the last 25 years, marine morbilliviruses have caused high mortality in cetaceans and pinnipeds worldwide resulting in the death of tens of thousands of marine mammals. The severity of infection has resulted in population level consequences in susceptible species. In 1988 and in 2002 phocine distemper virus (PDV) killed over half the population of harbor seals in Europe. Relatively conserved strains of PDV that exhibit little genetic variability appear to induce few differences in host adaptation, pathogenesis and epidemiology. In contrast, the more divergent group of cetacean morbillivirus (CeMV) exhibits a broader range of host adaptation, pathogenesis and epidemiology patterns making it increasingly difficult to predict and manage outbreaks in cetaceans.
Dolphin morbillivirus is currently implicated in an Unusual Mortality Event (UME), involving over 1,500 bottlenose dolphin deaths in the U.S. Northeast and Southeast Atlantic. Despite several large scale epizootic events due to various strains of morbillivirus, susceptibility, pathogenesis and epidemiology are still not fully understood. To predict the effects of the virus and to develop any effective individual or population wide models and interventions, including the possibility of vaccination programs, an understanding of susceptibility, transmission and reservoir dynamics of the viruses are necessary. In this project, we will examine the range of host susceptibility and pathogenesis to DMV by examining tissues to identify host reservoir species and using in vitro infection experiments to test susceptibility.