Herpesvirus infection in beluga whales Ole Nielsen, Kathleen A. Burek-Huntington, Lisa L. Loseto, Maria Morell, and Carlos H. Romero

1. Little is known about infectious diseases in beluga. Identifying the viruses that infect belugas and lead to disease can give us clues as to why some populations are healthier than others. The health of belugas is important for two reasons. First, belugas are harvested by hunters who are increasingly concerned with the wholesomeness of the whales they eat. Second, some populations of belugas (e.g., the Cook Inlet belugas in Alaska, USA) are considered Endangered and continue to decline; health may be a factor in these declines.

2. We attempted to isolate and study viruses in beluga using standard cell culture methodology. Isolated viruses were identified by transmission electron microscopy (TEM) and polymerase chain reaction (PCR). Looking at prepared slides of skin lesions under the microscope we attempted to link our virus isolation results to the skin abnormalities we were seeing in some of the Alaskan belugas and attribute a viral cause for these lesions.

3. A novel strain of Alphaherpesvirus designated "Beluga Whale Herpes Virus" or BWHV was isolated from numerous samples from belugas from Alaska and the Inuvialuit Settlement Region (ISR), Northwest Territories, Canada. BWHV was found in skin lesions from sick/dead Alaskan belugas that demonstrated tissue pathologies consistent with herpesvirus infection in other animals. Many ISR belugas were infected with BWHV but generally in better health and did not have the skin lesions observed on Alaskan belugas. We hypothesize that BWHV can be found in all populations of beluga world-wide and may cause significant morbidity in some individuals.

4. We now have a greater understanding of beluga health because of health assessments, including traditional ecological knowledge (TEK), of hunter-harvested, dead/stranded, and live-captured belugas. In particular, samples obtained for this study allowed us to isolate and characterize a new virus, BWHV, from both Alaskan and Canadian belugas. Only through continued monitoring and co-operation with hunters and wildlife management partners can we continue to successfully manage sustainable beluga populations.

The beluga whale is an Arctic cetacean species with a circumpolar distribution and is hunted for subsistence use by indigenous peoples. Hunters are increasingly concerned about the health of the belugas they harvest and feed to their families. Health monitoring is carried out opportunistically in Alaska while hunt monitoring in the Inuvialuit Settlement Region (ISR) in Canada has been has been ongoing since the 1950's.

Herpesviruses are perhaps one of the most successful viruses, capable of infecting most vertebrates which they have done for millions of years. Herpesviruses cause a variety of diseases in humans and animals and most of us are familiar with cold sores and chickenpox both caused by "herpes". Whales and dolphins are known to be infected as well, but herpes infection has not been extensively studied in belugas.

We were able to isolate a new species of herpesvirus, "Beluga Whale Herpes Virus" (BWHV), from both healthy and sick belugas from the ISR and Alaska. This is the first report of the isolation of a herpesvirus from belugas. The virus was found in three different populations of belugas and we hypothesize that it is circulating in all populations of belugas world-wide.

By examining the virus's genetic sequences we found it to be closely related to other herpes species infecting whales and also distantly related to human herpesviruses. This species of virus does not appear to cause disease in humans and poses no threat to hunters coming in contact with infected belugas.

We were also able to isolate the virus from some skin lesions in sick Alaskan belugas that had tissue pathologies consistent with herpes infection. This finding indicates that BWHV is able to cause significant disease in at least some individuals.

Only through continued health monitoring and assessments on healthy as well as dead/stranded belugas can we effectively understand the threats that infectious diseases pose to belugas. Wildlife managers can use the information provided by studies such as this one to ensure that we have sustainable beluga populations for future generations.

Report Abuse

If you feel that this video content violates the Adobe Terms of Use, you may report this content by filling out this quick form.

To report a Copyright Violation, please follow Section 17 in the Terms of Use.