Characterization of Newcastle disease viruses in wild and domestic birds in Luxembourg from 2006 to 2008.
- Clinical and Applied Virology
- Vaccinology and B Cell Immunology
Newcastle disease virus (NDV) is one of the most important viral diseases of birds. Wild birds constitute a natural reservoir of low virulent viruses while poultry are the main reservoir of virulent strains. Exchange of virus between both reservoirs represents a risk for both bird populations. Samples from wild and domestic birds collected between 2006 and 2010 in Luxembourg were analyzed for NDV. Three similar avirulent genotype I strains were found in ducks during consecutive years, suggesting that the virus may have survived and spread locally. However, separate introductions cannot be excluded because no recent complete F gene sequences of genotype I from other European countries are available. Detection of vaccine-like strains in wild waterbirds suggested the spread of vaccine strains, despite the non-vaccination policy in Luxembourg. Among domestic birds, only one chicken was positive for a genotype II strain differing from the LaSota vaccine and exhibiting a so far unrecognized fusion protein cleavage site of predicted lowvirulence. Three genotype VI strains from pigeons were the only virulent strains found. The circulation of NDV in wild and free-ranging domestic birds warrants a continuing surveillance because of increased concern that low virulent wild bird viruses could become more virulent in domestic populations.