Killian Mary Lea
Diagnostic Virology Laboratory, US Department of Agriculture, National Veterinary Services Laboratories, APHIS, 1920 Dayton Ave., Ames, IA, 50010, USA,
Methods Mol Biol. 2014;1161:3-9. doi: 10.1007/978-1-4939-0758-8_1.
The hemagglutination assay (HA) is a tool used to screen cell culture isolates or amnioallantoic fluid harvested from embryonated chicken eggs for hemagglutinating agents, such as type A influenza. The HA assay 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 1 hemagglutinating unit (HAU) is equal to approximately 5-6 logs of virus. It is inexpensive and relatively simple to conduct. Several factors (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 describes the methods validated and used by the US National Veterinary Services Laboratories for screening and identification of hemagglutinating viruses.
血凝试验（HA）是一种用于筛查细胞培养分离物或从鸡胚收获的羊水尿囊液中是否存在血凝剂（如甲型流感病毒）的工具。HA试验并非鉴定试验，因为其他病原体也具有血凝特性。HA试验可检测活病毒和灭活病毒。通常需要先通过鸡胚或细胞培养进行病毒分离扩增，才能从临床样本中检测到HA活性。该试验在一定程度上具有定量性，因为1个血凝单位（HAU）约等于病毒的5至6个对数。它成本低廉且操作相对简单。每次进行试验时，有几个因素（鸡红细胞质量、实验室温度、实验室设备、操作人员的技术专长）可能会导致试验结果解读出现细微差异。本章介绍了美国国家兽医服务实验室用于筛查和鉴定血凝病毒的经过验证和使用的方法。
