The 1992 Epizootic of Newcastle Disease in Double-Crested Cormorants in North America

Abstract

In the summer of 1992, morbidity and mortality in juvenile double-crested cormorants (Phalacrocorax auritus; DCC) attributable to Newcastle disease virus (NDV) was observed for the first time in seven northern USA states and one Canadian province, and recurred in three western Canadian provinces. Based on clinical signs and laboratory diagnostic findings, DCC mortality from NDV occurred in 59 of the 63 nesting colonies and two of three non-colony sites investigated. An estimate of in excess of 20,000 DCC died, with mortality rates ranging from Ͻ1 to 37% in Great Lakes colonies to 20 to 92% in Minnesota (USA) and North and South Dakota (USA) colonies. Sick juvenile white pelicans (Pelecanus erythrorhynchos) exhibiting signs similar to sick cormorants, and dead pelicans were observed in Minnesota and North Dakota. Mortality rates in pelican colonies were as high as in the adjacent cormorant colonies, but no cause for the mortality of an estimated 5,000 pelicans was determined. No evidence of NDV was found in other species nesting in proximity to affected cormorants. Although the source of the NDV infection is unknown in cormorants, the simultaneous onset of the epizootics in juvenile birds over a wide geographic area implies that the virus was acquired by adults prior to migration and was carried back to nest sites, exposing susceptible nestlings. The possible transmission of this virus from free-ranging wild birds to domestic poultry is a concern. Based on repeated epizootics in cormorants since 1990, NDV seems to be established in DCC.

Clinicopathological Characterization in Poultry of Three Strains of Newcastle Disease Virus Isolated From Recent Outbreaks

“…The involvement of the respiratory system was minimal. As described for the cormorants infected with NDV, 5,10,[22][23][24] clinicopathological findings in the chickens involved mainly the nervous system, suggesting that the tropism and the behavior of the virus were similar in different hosts. The development of clinical disease in chickens inoculated with a strain rescued from wild birds (cormorant) underlines the important role that wild birds could have in the natural or accidental transmission of virulent strain to commercial flocks.…”

Hematology, Plasma Chemistry, and Serology of the Flightless Cormorant (Phalacrocorax Harrisi) in the Galápagos Islands, Ecuador

“…On Isabela Island, where part of the flightless cormorant population resides, backyard chickens and broiler chicken farms are found and antibodies to Newcastle disease virus (NDV) have been reported (Gottdenker et al, 2005). Mortality associated with NDV has occurred in double-crested cormorants in North America (Glaser et al, 1999), and it is uncertain how naÏve flightless cormorants would respond to infection. Furthermore, other poultry diseases detected in the islands (Gottdenker et al, 2005) could affect the cormorants.…”

Serosurvey for Selected Infectious Agents in Two Sympatric Species of Cormorants (Phalacrocorax Atriceps and Phalacrocorax Magellanicus) From Coastal Patagonia, Argentina

“…There are no studies on the health status of cormorants in Patagonia, and most disease reports in cormorants worldwide are limited to outbreaks of Newcastle disease (Blaxland, 1951;Wobeser et al, 1993;Glaser et al, 1999;Artois et al, 2002, Diel et al, 2012. Notwithstanding, Travis et al (2006) found antibodies for avian adenovirus and Chlamydophila psittaci in the Flightless Cormorant (Phalacrocorax harrisi) in the Galápagos Islands, Ecuador.…”