Collaborative studies on the development of national reference standards for potency determination of H7N9 influenza vaccine

Development and characterization of standard reagents for cell-based prepandemic influenza vaccine products

“…The preparation process of these reagents, from virus production to animal immunization, is time-consuming (usually requiring 3~6 months) and difficult. 5 The suitability of Table 5. HI titers of goat antisera generated by immunization with purified H7 antigens.…”

“…28 Similar studies have previously been reported by other scientists. 5,32,33 Additionally, the cell-derived antiserum was compared with the egg-derived antiserum through SRID assays. Cross-relation analysis by SRID assay revealed good consistency among the vaccine antigens from different sources.…”

“…This technique is used for vaccines obtained using the product-release method recommended by the WHO and national regulatory agencies. 5 The reference reagents used in the SRID assay are produced primarily by egg-derived candidate vaccine viruses (CVVs).…”

A novel approach for preparation of the antisera reagent for potency determination of inactivated H7N9 influenza vaccines

“…Previous studies have demonstrated the feasibility of alternative methods for preparing potency antiserum for the SRID assay, and a recent report describes the development of national reference standards for H7N9 vaccines, including a potency antiserum made by immunization with recombinant HA. 22 However, the antiserum lots made using the VLP booster immunization that is described in this report were the first influenza vaccine potency antisera distributed by a WHO ERL to vaccine manufacturers for quantifying the HA in their H7N9 vaccines. Thus, this report serves to document the novel approach used to produce this particular vaccine reagent, as well as to provide additional support for the feasibility of using alternative methods for reagent production.…”

Desenvolvimento da produção da vacina contra uma possível gripe pandêmica A (H7N9).

“…As fases são divididas em números de 1 a 6 que estabelecem níveis mais baixos, 1 e 2 quando são identificados vírus da gripe que prevalecem em animais (reservatórios naturais) e os primeiros casos O tratamento antiviral ainda é considerado uma técnica cara quando utilizada em larga escala, além disso, apresenta restrições para crianças e mulheres grávidas por manifestar efeitos colaterais (CDC, 2010b). Entretanto, em casos de epidemias provocadas por vírus emergentes, a manufatura e a distribuição das vacinas podem demorar de 6 a 8 meses, sendo mais eficaz, nesses casos, o uso dos antivirais para a contenção das epidemias (LONGINI JUNIOR et al, 2004).…”