title: Virulence of H5N1 influenza virus in Cattle Egrets (Bubulcus ibis).
abstract: In Vietnam, Cattle Egrets (Bubulcus ibis) are common in a variety of habitats, such as freshwater marshes, beaches, and paddy fields. They are also found associated with cattle (Bos spp.) and occasionally with pigs (Sus scrofa), goats (Capra hircus), and horses (Equus caballus) and are kept for insect control in households. In this study, six Cattle Egrets were experimentally infected intranasally with highly pathogenic avian influenza (AI) A/duck/Vietnam/40D/04 (H5N1) to investigate a possible epidemiologic role for Cattle Egrets in outbreaks of H5N1 AI in Vietnam. The Cattle Egrets were highly susceptible to the infection and either died within a week or had to be euthanized. Five uninfected chickens housed with the inoculated Cattle Egrets from day 1 to day 8 postinfection showed no signs of disease or mortality. This observation was most probably due to the low-level virus shedding by the Cattle Egrets. We concluded that Cattle Egrets are not significant reservoir hosts for H5N1 AI virus.
authors: Virology Department, National Institute of Veterinary Research, 86 Truong Chinh Street, Dong Da District, Hanoi, Vietnam. ducphuong67@yahoo.com
authors: Do Quy
authors: do Q
authors: Phuong
authors: Nguyen Tien
authors: NT
authors: Dung
authors: Poul Henrik
authors: PH
authors: Jörgensen
authors: Dao Thanh
authors: DT
authors: Van
authors: Dao Duy
authors: DD
authors: Tung
authors: Jens Peter
authors: JP
authors: Christensen
mesh_terms: D000818:Animals; D000829:Animals, Domestic / Q000821:virology; D000835:Animals, Wild / Q000821:virology; D001717:Birds; D002645:Chickens; D004197:Disease Reservoirs / Q000662:veterinary* / Q000821:virology; D004198:Disease Susceptibility / Q000662:veterinary* / Q000821:virology; D053124:Influenza A Virus, H5N1 Subtype / Q000472:pathogenicity*; D005585:Influenza in Birds / Q000473:pathology / Q000635:transmission* / Q000821:virology*; D014744:Vietnam; D017201:Virus Shedding