Aim: To compare usage of native and formalinized erythrocytes from different animal species in hemagglutination inhibition (HI) test for detection of level of specific antibodies to H5N1 influenza virus in sera of mammals.
Materials and methods: Level of anti-H5 antibodies to influenza H5 control antigen and to influenza viruses A/Common gull/Chany/2006 (H5N1), A/duck/Tuva/01/06 (H5N1), A/Anas platyrhynchos/Chany Lake/9/03 (H5N3) was determined by hemagglutination inhibition test in two influenza A (H5) reference antisera as well as in ferret antisera to native strains of avian influenza virus. Equine, rhesus macaque, sheep, guinea pig, goose, and chicken erythrocytes were used.
Results: Using reference antisera, H5 hemagglutinin was detected in all tested antigens with all used erythrocytes. While testing ferret antisera in HI test with reference antigen, anti-H5 antibodies were not detected or detected in extremely low titre (1/80) and only with equine erythrocytes. In most cases, titers of anti-H5 antibodies in HI test with formalinized erythrocytes were higher than with native ones.
Conclusion: During monitoring for antibodies to H5N1 avian influenza virus in human population it is necessary to use native strains of A/H5N1 along with reference antigen. It is possible to use formalinized equine, rhesus macaque, goose, and chicken erythrocytes.