Since their introduction in the human population in 1968, influenza A viruses of the H3 subtype have evolved continuously to escape recognition and neutralization by antibodies, a component of our immune system. These changes have also reduced the ability of viruses to bind red blood cells, termed hemagglutination, a trait that is widely utilized in laboratories to measure levels of infectious influenza virus in clinical specimens.
Viroclinics Biosciences found a way to detect such virus variants by targeting a more conserved part of the virus that is present in all influenza A virus strains tested since 1934 to date. The rise of virus variants missed by hemagglutination-based techniques was documented for the period between 1999 and 2012, in close collaboration with Erasmus MC Viroscience department scientists. These results and the validity of the new method for quantitating infectious virus in clinical specimens is now reported in Journal of Clinical Microbiology.
The new method requires no additional patient material and forms a prime asset for studies on the effectiveness of novel antiviral treatments against moving targets such as influenza A viruses.
Article: Detection of Nonhemagglutinating Influenza A(H3) Viruses by Enzyme-Linked Immunosorbent Assay in Quantitative Influenza Virus Culture, C. A. van Baalen, C. Elsa, L. Sprong, R. van Beek, E. van der Vries, A. D. M. E. Osterhausa, and G. F. Rimmelzwaana, Journal of Clinical Microbiology, DOI: 10.1128/JCM.03575-13, published online 12 March 2014.