From 2003 to 2013, Indonesia had the highest number of avian influenza A cases in humans, with 192 cases and 160 fatalities. Avian influenza is caused by influenza virus type A, such as subtype H5N1. This virus has two glycoproteins: hemagglutinin and neuraminidase, which will become the primary target to be neutralized by vaccine. Vaccine is the most effective immunologic intervention. In this...

Full-genome analysis was conducted on the first isolate of a highly pathogenic avian influenza A(H5N1) virus from a human in North America. The virus has a hemagglutinin gene of clade 2.3.2.1c and is a reassortant with an H9N2 subtype lineage polymerase basic 2 gene. No mutations conferring resistance to adamantanes or neuraminidase inhibitors were found.

The contribution of influenza A neuraminidase antibodies to the reaction with whole virus in an enzyme-linked immunosorbent assay (ELISA) was assessed by specific absorption of rabbit hyperimmune sera. Although measurable and independent, the effect of neuraminidase antibodies was less than that of hemagglutinin antibodies. Recombinants with an irrelevant hemagglutinin were used successfully as...

Neuraminidase treatment of human peripheral blood lymphocytes uncovers cell surface receptors that bind purified A hemagglutinin from the snail Helix pomatia. No hemagglutinin was bound to untreated lymphocytes. Binding studies with (125)I-labeled hemagglutinin suggested that the number of receptors on neuraminidase-treated lymphocytes was approximately 1.10(6)/cell. The apparent association co...

The nucleotide sequence of a cloned cDNA copy of the mRNA coding for the hemagglutinin-neuraminidase of the paramyxovirus SV5 was determined. There was a single large open reading frame on the mRNA which encoded a protein of 565 amino acids with a molecular weight of 62,134. The deduced amino acid sequence indicated that the only major hydrophobic region in the protein sufficiently long to anch...

The antigenicity of two parainfluenza=3 virus strains, a "neuraminidasestrong" and a "neuraminidase-weak," was compared. For both strains the amount of hemagglutinin units was equal. The antibody responses to neuraminidase and hemagglutinin were measured on samples of serum and nasal secretion and were found to be similar, irrespective of the strain used for immunization. Anti-neuraminidase act...

Newcastle disease virus isolates from chickens in eastern Uganda in 2001 were found to be velogenic by fusion protein cleavage site sequence analysis and biological characterization; the intracerebral pathogenicity index was 1.8. Analysis of their hemagglutinin-neuraminidase protein gene sequences revealed a novel genotype unrelated to those that caused previous outbreaks.

An H10N9 avian influenza virus (AIV) strain, A/Chicken/Jiangsu/RD5/2013, was isolated in China. The hemagglutinin (HA) and neuraminidase (NA) genes in this strain originated from H10N1 and H7N9 AIVs, respectively, and the other genes derived from H7N3 AIVs. Sequence analysis implies that the H10N9 AIV may be an NA gene donor for the human H7N9 influenza viruses.

Three cases of Newcastle disease virus (NDV) found in nature had the lentogenic motif (112)G-R-Q-G-R-L(117) in their fusion protein cleavage sites. However, both intracerebral pathogenicity and intravenous pathogenicity indexes showed that these NDV isolates were virulent. In comparison with the LaSota live virus vaccine, these viruses had significant genetic variations in the hemagglutinin-neu...