Background Vaccine effectiveness (VE) estimates for 2015-2016 seasonal influenza vaccine are reported from Canada's Sentinel Practitioner Surveillance Network (SPSN). This season was characterized by a delayed 2009 pandemic influenza A(H1N1) virus (A[H1N1]pdm09) epidemic and concurrent influenza B(Victoria) virus activity. Potential influences on VE beyond antigenic match are explored, includin...

To monitor oseltamivir-resistant influenza viruses A (H1N1) (ORVs) with H275Y in neuraminidase (NA) in Japan during 2 influenza seasons, we analyzed 3,216 clinical samples by NA sequencing and/or NA inhibition assay. The total frequency of ORVs was 2.6% (45/1,734) during the 2007-08 season and 99.7% (1,477/1,482) during the 2008-09 season, indicating a marked increase in ORVs in Japan during 1 ...

BACKGROUND Serum antibody to influenza can be used to identify past exposure and measure current immune status. The two most common methods for measuring this are the hemagglutination inhibition assay (HI) and the viral neutralization assay (NT), which have not been systematically compared for a large number of influenza viruses. METHODS A total of 151 study participants from near Guangzhou, ...

Antigenic characterization based on serological data, such as Hemagglutination Inhibition (HI) assay, is one of the routine procedures for influenza vaccine strain selection. In many cases, it would be impossible to measure all pairwise antigenic correlations between testing antigens and reference antisera in each individual experiment. Thus, we have to combine and integrate the HI tables from ...

A new latex agglutination test for rubella virus was used to test sera with a hemagglutination inhibition titer of -8 (97 specimens) or >256 (158 specimens). Maximum latex agglutination test sensitivity was achieved when low-titer sera were tested undiluted and high-titer sera were diluted (1:10). A modification of the protocol of the manufacturer resulted in a latex agglutination-hemagglutinat...

A new latex agglutination test for rubella virus was used to test sera with a hemagglutination inhibition titer of less than or equal to 8 (97 specimens) or greater than or equal to 256 (158 specimens). Maximum latex agglutination test sensitivity was achieved when low-titer sera were tested undiluted and high-titer sera were diluted (1:10). A modification of the protocol of the manufacturer re...

Three feline virus isolates were shown to be members of the reovirus group by their growth characteristics in cell cultures, physicochemical properties, and appearance under an electron microscope. Their close serological relationship to, or identity with, human reovirus type III was revealed by hemagglutination, hemagglutination inhibition, serum neutralization, and gel diffusion tests. One fe...

Goose erythrocytes preserved with glutaraldehyde were compared with fresh cells in hemagglutination and hemagglutination-inhibition tests for arbovirus antigens and antibodies. The glutaraldehyde-fixed cells were as sensitive and specific as theresh erythrocytes and were stable at 4 degrees C for 6 months.

A new diluent (ADGP) for the rubella virus hemagglutination (HA) and hemagglutination-inhibition (HI) tests is described. It was found that the HA and HI titers and the erythrocyte agglutination pattern were improved in ADGP compared to previously described diluents. The influence of the components of ADGP and of various test conditions on optimal HA and HI results were examined.

a dot immunobinding assay ( dia) was used for a quantitative and qualitative assay of rubella antibody. purified antigen and conjugated anti-human immunoglobulin (rahlg) were prepared. nitrocellulose paper dotted with the antigen was added to serially diluted sera or blood samples. the reacting antibodies were visualized by a peroxidase system. development of a colored insoluble substrate was t...