Hemagglutination Assay for Influenza Virus
- 112 Downloads
The hemagglutination assay (HA) is a tool used to screen cell culture supernatant or amniotic-allantoic fluid harvested from embryonated chicken eggs for hemagglutinating agents, such as type A influenza. The HA is not an identification assay, as other agents also have hemagglutinating properties. Live and inactivated viruses are detected by the HA test. Amplification by virus isolation in embryonated chicken eggs or cell culture is typically required before HA activity can be detected from a clinical sample. The test is, to some extent, quantitative as one hemagglutinating unit (HAU) is equal to approximately 5–6 log10 of virus. It is inexpensive and relatively simple to conduct. Several factors (e.g., the quality of chicken erythrocytes, laboratory temperature, laboratory equipment, technical expertise of the user) may contribute to slight differences in the interpretation of the test each time it is run. This chapter will describe the methods validated and used by the US National Veterinary Services Laboratories for screening and identification of hemagglutinating viruses.
Key wordsHemagglutination Avian influenza virus Type A influenza Influenza detection Virus titer
- 1.WHO manual on animal influenza diagnosis and surveillance (2002). World Health Organization, Geneva, SwitzerlandGoogle Scholar
- 2.Grimes S (2002) A basic laboratory manual for the small-scale production and testing of I-2 newcastle disease vaccine. Food and agriculture organization of the United NationsGoogle Scholar
- 3.Swayne DE, Senne D, Suarez DL (2008) Avian influenza. In: Dufour-Zavala L, Swayne DE, Glisson J et al (eds) Isolation and identification of avian pathogens, 5th edn. American Association of Avian Pathologists, Jacksonville, FL, pp 128–134Google Scholar
- 5.OIE (2018) Manual of diagnostic tests and vaccines for terrestrial animals: avian influenza. World Organization for Animal Health (OIE). http://www.oie.int/standard-setting/terrestrial-manual/access-online/. Accessed 14 Jan 2019