Morbillivirus infection in cetaceans stranded along the Italian coastline: Pathological, immunohistochemical and biomolecular findings

POPs in free-ranging pilot whales, sperm whales and fin whales from the Mediterranean Sea: Influence of biological and ecological factors

“…This epidemic, believed to have spread through the Gibraltar Strait, was found in stranded striped dolphins (Stenella coeruleoalba) and bottlenose dolphins (Tursiop truncatus), as during the first epizootic event in 1990-1991. For the first time DMV was reported in 25 long-finned pilot whales and four fin whales stranded along the Tuscan coast of Italy Borrell, 1994a, 1994b;Fernàndez et al, 2008;Keck et al, 2010;Di Guardo et al, 2013;Mazzariol et al, 2012). Histoand toxicological analysis showed how all the individuals which succumbed to the infection were highly contaminated, suggesting that accumulation of high levels of hazard substances increase the sensibility of marine mammals to viral infections Borrell, 1994a, 1994b;Gabrielsen, 2007;Mazzariol et al, 2012).…”

Dolphin Morbillivirus Infection in a Captive Harbor Seal (Phoca vitulina)

“…DMV poses a major threat for free-ranging cetaceans. It has been responsible for two epidemics in the Mediterranean Sea (6): the first outbreak (1990 to 1992) affected striped dolphins (Stenella coeruleoalba) (7,8), while the second (2006 to 2011) involved several other species besides striped dolphins, including pilot whales (Globicephala melas), bottlenose dolphins (Tursiops truncatus), Risso's dolphins (Grampus griseus), and fin whales (Balaenoptera physalus) (1,(8)(9)(10)(11). Among pinnipeds, mortality events worldwide have involved harbor seals (Phoca vitulina), gray seals (Halichoerus grypus), Baikal seals (Pusa sibirica), and Caspian seals (Pusa caspica) by either CDV or PDV, an agent closely related to CDV (7).…”

“…Indeed, the repeated independent emergence of CDV in novel species appears to be associated with its adaptation to receptor-binding regions determining virus-host specificity (14). Furthermore, throughout the 2006 to 2011 morbillivirus epidemic in the Mediterranean Sea, DMV infection was repeatedly reported in several species (1,(8)(9)(10)(11). Another unprecedented finding of our study is that DMV may not only infect but also cause severe disease and subsequent mortality in harbor seals, without previous species adaptation, whereas DMV-like infection could not be established as the primary cause of mortality in the monk seals from Mauritania (7).…”

“…DMV has been frequently reported in association with secondary infections from opportunistic bacteria or protozoa such as Toxoplasma gondii (1,7,8,11). In seals, Aeromonas spp.…”

Cetacean morbillivirus in Northern and Southern Hemispheres

“…Furthermore, the agent recovered from the two T. aduncus individuals stranded along the Western Australia coastline was deemed to be, with exclusive reference to the N and P genes, the CeMV more closely related to Measles Virus (MeV) as well as to Peste des Petits Ruminants Virus (PPRV) and Rinderpest Virus (RPV), the archetype morbillivirus (Stephens et al, 2014). Intriguingly, no peculiar inflammatory lesions nor immunohistochemical (IHC) evidence of morbilliviral antigen were observed in the brain of these two animals (Stephens et al, 2014), differently from CeMV-infected cetaceans (Di Guardo and Mazzariol, 2013; Di Guardo et al, 2013) but also similarly to experimentally RPV-infected cattle (Wohlsein et al, 1993). In this respect, while CeMV sequences could be demonstrated in the brain and lung from approximately 40% of the striped dolphins ( Stenella coeruleoalba ) found stranded during the first mid of 2013 along the Tyrrhenian coast of Italy, IHC evidence of morbilliviral antigen was obtained from the brain of only one of these animals (Casalone et al, 2014).…”