Format

Send to

Choose Destination
Emerg Infect Dis. 2009 Aug;15(8):1252-9. doi: 10.3201/eid1508.081754.

Reproducibility of serologic assays for influenza virus A (H5N1).

Author information

1
University of Leicester, UK. iain.stephenson@uhl-tr.nhs.uk

Abstract

Hemagglutination-inhibition (HI) and neutralization are used to evaluate vaccines against influenza virus A (H5N1); however, poor standardization leads to interlaboratory variation of results. A candidate antibody standard (07/150) was prepared from pooled plasma of persons given clade 1 A/Vietnam/1194/2004 vaccine. To test human and sheep antiserum, 15 laboratories used HI and neutralization and reassortant A/Vietnam/1194/2004, A/turkey/Turkey/1/2005 (clade 2.2), and A/Anhui/1/2005 (clade 2.3.4) viruses. Interlaboratory variation was observed for both assays, but when titers were expressed relative to 07/150, overall percentage geometric coefficient of variation for A/Vietnam/1194/2004 was reduced from 125% to 61% for HI and from 183% to 81% for neutralization. Lack of reduced variability to clade 2 antigens suggested the need for clade-specific standards. Sheep antiserum as a standard did not reliably reduce variability. The World Health Organization has established 07/150 as an international standard for antibody to clade 1 subtype H5 and has an assigned potency of 1,000 IU/ampoule.

PMID:
19751587
PMCID:
PMC2815968
DOI:
10.3201/eid1508.081754
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for CDC-NCEZID Icon for PubMed Central
Loading ...
Support Center