Hemagglutination Assay (HA)
Overview
A classical assay for detecting and quantifying viruses (e.g., influenza) that agglutinate red blood cells.
Principle
- Serial dilutions of virus are incubated with RBCs. 
- Agglutination is visually assessed. 
- The highest dilution causing complete agglutination is recorded as the HA titer. 
Applications
- Virus quantification for influenza and other HA viruses 
- Standardization of input material for HAI assays 
- Rapid viral load estimation 
Deliverables from MIV
?? HA titers reported in HA units
?? Well plate images for documentation
?? Technical interpretation for assay planning