Avian Influenza Virus Antibodies in Pacific Coast Red Knots (Calidris canutus roselaari)

Abstract

ABSTRACT:Prevalence of avian influenza virus (AIV) antibodies in the western Atlantic subspecies of Red Knot (Calidris canutus rufa) is among the highest for any shorebird. To assess whether the frequency of detection of AIV antibodies is high for the species in general or restricted only to C. c. rufa, we sampled the northeastern Pacific Coast subspecies of Red Knot (Calidris canutus roselaari) breeding in northwestern Alaska. Antibodies were detected in 90% of adults and none of the chicks sampled. Viral shedding was not detected in adults or chicks. These results suggest a predisposition of Red Knots to AIV infection. High antibody titers to subtypes H3 and H4 were detected, whereas low to intermediate antibody levels were found for subtypes H10 and H11. These four subtypes have previously been detected in shorebirds at Delaware Bay (at the border of New Jersey and Delaware) and in waterfowl along the Pacific Coast of North America.

Intercontinental genetic structure and gene flow inDunlin (Calidris alpina), a potential vector of avian influenza

“…; Johnson et al. ) indicates that the evolution of new strains remains problematic and that Dunlin are a potential route for HPAI to reach and spread within North America.…”

“…This is particularly pertinent given that Dunlin are highly susceptible to infection with the H5N1 HPAI, and that some individuals may live to spread the disease, possibly after undergoing a migration (Hall et al 2011). Although only a few Dunlin sampled in western North America have been documented with actively shedding AI (Ip et al 2008;Iverson et al 2008;US-FWS and USGS 2011), the continued emergence of new HPAI strains (e.g., H5N8, H7N9) and the fact that most efforts to date have detected prior exposure (i.e., antibodies, see Pearce et al 2012;Johnson et al 2014) indicates that the evolution of new strains remains problematic and that Dunlin are a potential route for HPAI to reach and spread within North America.…”

Avian Influenza Virus Status and Maternal Antibodies in Nestling White Ibis (Eudocimus albus)

“…In the yellow-legged gull (Larus michahellis) and mallard, egg yolk AIV antibody prevalence, as determined by NP bELISA, is lower than adult antibody prevalence detected at the same time and location, indicating that not all antibody-positive females pass antibodies to their offspring [17,18]. Maternal AIV antibody passage is variable among aquatic birds; adult northeastern Pacific red knots (Calidris canutus roselaari) had an estimated AIV antibody prevalence of >90%, but no sampled nestlings (<2 weeks old, n = 16) had detectible antibodies based on bELISA analysis [30]. The mothers of the ibis nestlings in this study transferred antibodies to their offspring, and in many cases, these antibodies persisted for several weeks.…”

Red knots in Europe - a dead end host species or a new niche for highly pathogenic avian influenza?

“…Red knot subspecies Calidris canutus rufa and Calidris canutus roselaari have been investigated serologically in the U.S. (Delaware Bay and Alaska) with high antibody abundance against the LPAIV subtypes H3, H4, H10 and H11 (46, 1). Serological investigations of red knots have also been carried out in the East Atlantic Flyway with positive findings, while virological investigations yielded mostly negative results (12).…”