For almost 20 years, the neutralizing-epitope site specific for influenza B virus Victoria group isolates was conserved at the "tip" of the hemagglutinin molecule; however, it was not detected in half of the isolates from the 2002-2003 epidemic in Japan. Amino acid substitutions (D164E or N165K) were observed at the "tip", and the epitope was altered. The viral antigenicities were affected, and...

background and aims: influenza a virus infects birds and some mammalian including human. h1 and h3 subtypes are circulated in both human and birds’ population. to determine the prevalence of the mentioned subtypes in birds, different captive bird species in tehran zoo, and affiliated centers in tehran were investigated for virus infection. methods: in this study, between november 2008 and febru...

A sensitive immunoassay procedure for the detection of the thrombopoietic-stimulating factor (TSF) has been developed. This procedure Is similar to the hemagglutination-inhibition (HAl) technique that is available for erythropoietin. For the production of TSF, sheep were made thrombocytopenic by the Injection of antiplatelet serum. TSF from sheep sera was partially purified by column chromatogr...

An enzyme-linked immunosorbent assay (ELISA) using commercially available reagents was compared with standard serological tests for determination of antibody titers in patients with acute measles. The measles-specific ELISA was as sensitive as complement fixation, hemagglutination inhibition, and indirect fluorescent-antibody methods. The ELISA method used was simple, sensitive, inexpensive, an...

We studied whether MF59-adjuvanted influenza vaccine improves immunity against drifted influenza strains in institutionalised elderly with underling chronic health conditions. Sera from a randomized study, comparing MF59-adjuvanted (Sub/MF59, n = 72), virosomal (SVV, n = 39), and split (n = 88) vaccines, were retested using a hemagglutination inhibition (HI) assay against homologous (Northern H...

BACKGROUND In this prospective study we sought to examine seroepidemiological evidence for acute zoonotic influenza virus infection among Romanian agricultural workers. METHODS Sera were drawn upon enrollment (2009) and again at 12 and 24 months from 312 adult agriculture workers and 51 age-group matched controls. Participants were contacted monthly for 24 months and queried regarding episode...

A total of 1,136 samples from 289 households in four provinces in northern Laos were subjected to Japanese encephalitis virus (JEV) and dengue virus hemagglutination inhibition (DENV HI). Overall, antibodies to JEV were detected by HI in 620 (54.6%) of 1,136 people; of which 217 (19.1%) had HI activity against JEV only. Antibodies to DENV4 were detected by HI in 526 (46.3%) of 1,136 people; of ...

In this study, antibody responses after equine influenza vaccination were investigated among 1,098 horses in Korea using the hemagglutination inhibition (HI) assay. The equine influenza viruses, A/equine/South Africa/4/03 (H3N8) and A/equine/Wildeshausen/1/08 (H3N8), were used as antigens in the HI assay. The mean seropositive rates were 91.7% (geometric mean antibody levels (GMT), 56.8) and 93...