Influenza B virus in seals

National Influenza Center, Department of Virology, Erasmus University, Doctor Molewaterplein 50, 3015 GE Rotterdam, Netherlands.
Science (Impact Factor: 31.48). 06/2000; 288(5468):1051-3. DOI: 10.1126/science.288.5468.1051
Source: PubMed

ABSTRACT Influenza B virus is a human pathogen whose origin and possible reservoir in nature are not known. An influenza B virus was isolated from a naturally infected harbor seal (Phoca vitulina) and was found to be infectious to seal kidney cells in vitro. Sequence analyses and serology indicated that influenza virus B/Seal/Netherlands/1/99 is closely related to strains that circulated in humans 4 to 5 years earlier. Retrospective analyses of sera collected from 971 seals showed a prevalence of antibodies to influenza B virus in 2% of the animals after 1995 and in none before 1995. This animal reservoir, harboring influenza B viruses that have circulated in the past, may pose a direct threat to humans.

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