Pathogen Exposure in White Whales (Delphinapterus leucas) in Svalbard, Norway

Abstract

The Svalbard white whale (Delphinapterus leucas) population is one of the smallest in the world, making it particularly vulnerable to challenges such as climate change and pathogens. In this study, serum samples from live captured (2001–2016) white whales from this region were investigated for influenza A virus (IAV) antibodies (Abs) (n = 27) and RNA (n = 25); morbillivirus (MV) Abs (n = 3) and RNA (n = 25); Brucella spp. Abs; and Toxoplasma gondii Abs (n = 27). IAV Abs were found in a single adult male that was captured in Van Mijenfjorden in 2001, although no IAV RNA was detected. Brucella spp. Abs were found in 59 % of the sample group (16/27). All MV and T. gondii results were negative. The results show that Svalbard white whales have been exposed to IAV and Brucella spp., although evidence of disease is lacking. However, dramatic changes in climate and marine ecosystems are taking place in the Arctic, so surveillance of health parameters, including pathogens, is critical for tracking changes in the status of this vulnerable population.

A Review of Circumpolar Arctic Marine Mammal Health—A Call to Action in a Time of Rapid Environmental Change

“…Warmer water temperatures might play a role in the prolonged survival of oocysts of T. gondii in the future, increasing the risk of transport into the Arctic via north-flowing currents such as the North Atlantic Current or though marine invertebrate filter feeders [ 228 ]. White whales (n = 27) from Svalbard, Norway, were tested for T. gondii but were found to be negative [ 237 ], although antibodies have been detected in white whales in the Sea of Okhotsk [ 238 ]. Whilst T. gondii is currently a low mortality risk in the Arctic, an increased incidence could occur if the overall health of populations deteriorates.…”

“…Serological monitoring has confirmed the presence of influenza A in the Canadian Arctic, with white whales and ringed seals being serologically positive; antibodies have also been confirmed in narwhal and bowhead whales [ 292 , 293 ]. In addition, influenza A antibodies have also been detected in white whales in Svalbard, Norway, and in Russia, though there are no reports of clinical disease [ 237 ].…”

Zoonotic Animal Influenza Virus and Potential Mixing Vessel Hosts

“…However, we did not find data on natural infection with IAV, although antibodies against IAVs were detected in guinea pigs raised as livestock in Ecuador [375]. Whales have also been found to be infected with IAV [376][377][378][379]. Mathematical models predicted that AIV transmission by whales via faecal matter along the Atlantic Coast was several times greater than that by migratory birds [380].…”