24 pad nitrocellulose glass slides with a set of 33 HA1 proteins printed on each pad. The slides can be used for HA antibody profiling for group level assessment of exposures to influenza viruses in small sample volumes from humans and animals (birds, horses, pigs, bats, carnivores a.o.) in very small volumes of serum (10 μL). Each slides can be used for 24 sera. Scanning and analysis services are included.