This study was carried out to verify the possibility that ducks are sources of Newcastle disease (ND) virus infection for chickens in mixed flocks. Immunosuppressed (IS) and non immunosuppressed (NIS) birds, at three different antibody levels (medium, low and absent) were used; the titres having been induced through vaccination, and Immunosuppression done using dexamethazone. Each of the 3 resp...

This study described some essential viral and sera-characteristics of A/H7N9 virus infection in a 61-year old case patient. With the antiviral therapy and respiratory support, the patient showed a significant decrease of viral loads from 6.72 log10 copies/mL to 0 in 22 days, and a correlated increase of serum hemagglutination inhibition titers during the same period. Phylogenetic analysis demon...

A total of 104 elderly patients were immunized with one or two doses of the commercial 1985-1986 inactivated influenza vaccine formulation. Two types of vaccines (split virus [SV] vaccine and whole virus [WV] vaccine) and one or two doses 1 month apart were given. No difference in local or systemic reactions was noted among the four groups. The reciprocal geometric mean hemagglutination inhibit...

BACKGROUND The recent H1N1 influenza pandemic illustrated the shortcomings of the vaccine manufacturing process. The A/California/07/2009 H1N1 pandemic influenza vaccine or A(H1N1)pdm09 was available late and in short supply as a result of delays in production caused by low yields and poor antigen stability. Recombinant technology offers the opportunity to shorten manufacturing time. A trivalen...

INTRODUCTION .............. ................................ 591 DISCOVERY AND DEFINITIONS ............................................. 591 SEROLOGICAL METHODS ............................................. 592 Hemagglutination (HA), Hemolysis, and Hemagglutination Inhibition (HAI) ... 592 Other Serological Methods ............................................. 593 CHEMISTRY .......................

Both preexisting immunity to influenza and age have been shown to be correlates of influenza vaccine responses. Frailty, an indicator of functional impairment in older adults, was also shown in one study to predict lower influenza vaccine responses among nonveterans. In the current study, we aimed to determine the associations between frailty, preexisting immunity, and immune responses to influ...

BACKGROUND H5 DNA priming was previously shown to improve the antibody response to influenza A(H5N1) monovalent inactivated vaccine (MIV) among individuals for whom there was a 24-week interval between prime and boost receipt. This study defines the shortest prime-boost interval associated with an improved response to MIV. METHODS We administered H5 DNA followed by MIV at intervals of 4, 8, 1...

It was customary for medical students with some ambition to seek their way to a biomedical research group. I was intrigued by viruses, and virology was one of the few subjects in medical school that I studied with real interest. Next, in late 1966, I was incredibly lucky to meet Antti Vaheri (later Professor of Virology) who had just returned to Finland from the Wistar Institute in Philadelphia...

Antibody titers measured by hemagglutination inhibition (HAI) correlate with protection against influenza virus infection and are used to specify criteria for vaccine licensure. In a randomized, controlled trial of seasonal influenza vaccination in 773 children aged 6-17 years, we estimated that HAI titers of 1:40 against A(H1N1)pdm09 and B(Victoria lineage) were associated with 48% (95% confid...

Among 368 Thai men who have sex with men with paired serum samples collected before and during the 2009 H1N1 influenza pandemic, we determined influenza A (H1N1)pdm09 seroconversion rates (≥4-fold rise in antibody titers by hemagglutination inhibition or microneutralization assays). Overall, 66 of 232 (28%) participants seroconverted after the first year of A(H1N1)pdm09 activity, and 83 of 234 ...