Dennis J. Alexander

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Newcastle disease (ND), caused by avian paramyxovirus serotype 1 (APMV-1) viruses, is included in List A of the Office International des Epizooties. Historically, ND has been a devastating disease of poultry, and in many countries the disease remains one of the major problems affecting existing or developing poultry industries. Even in countries where ND(More)
A sequence 375 nucleotides in length, which included the region encoding the cleavage activation site and signal peptide of the fusion protein gene, was determined for 174 isolates of Newcastle disease virus (avian paramyxovirus type 1). These were compared with the sequences of 164 isolates published on GenBank, and the resulting alignment was analysed(More)
Substantial variation in the virulence of Newcastle disease virus (NDV) isolates means that the detection of NDV or evidence of infection is insufficient for an adequate diagnosis, as control measures for avirulent viruses are very different to those for virulent viruses. Diagnosis therefore requires further characterization, at least as to whether an(More)
Novel H1N2 influenza A viruses which were first detected in pigs in Great Britain in 1994 were examined antigenically and genetically to determine their origins and establish the potential mechanisms for genetic reassortment. The haemagglutinin (HA) of all swine H 1 N2 viruses examined was most closely related to, but clearly distinguishable both(More)
 Outbreaks of avian influenza due to an H7N1 virus of low pathogenicity occurred in domestic poultry in northern Italy from March 1999 until December 1999 when a highly pathogenic avian influenza (HPAI) virus emerged. Nucleotide sequences were determined for the HA1 and the stalk region of the neuraminidase (NA) for viruses from the outbreaks. The HPAI(More)
Between December 2003 and January 2004 highly pathogenic avian influenza (HPAI) H5N1 infections of poultry were declared in China, Japan, South Korea, Laos, Thailand, Cambodia, Vietnam, and Indonesia. In 2004 an outbreak was reported in Malaysia. In 2005 H5N1 outbreaks were recorded in poultry in Russia, Kazakhstan, Mongolia, Romania, Turkey, and Ukraine,(More)
The amino acid sequence at the F2/F1 cleavage site of the F0 fusion protein of 17 strains of Newcastle disease virus (NDV) was deduced from sequencing a 32 nucleotide area of the genome by reverse transcription and polymerase chain reaction (PCR) techniques. With the addition of sequences at the same area previously published for 9 other viruses comparisons(More)
This paper reviews the worldwide situation regarding avian influenza infections in poultry from 1997 to March 2004. The increase in the number of primary introductions and the scientific data available on the molecular basis of pathogenicity have generated concerns particularly for legislative purposes and for international trade. This has led to a new(More)
From the end of March to the beginning of December 1999, an epidemic of low pathogenicity avian influenza (LPAI) affected the industrial poultry population of northern Italy. The virus responsible for the epidemic was subtyped as H7N1 with an intravenous pathogenicity index (IVPI) of 0.0, and a deduced amino acid sequence of the region coding for the(More)