ATP6AP1 and infection: To date, the intrastrain variability of the EEHV1B ORF-Q protein appears much lower than that observed for the EEHV1A strains; moreover, its homology with EEHV1A strains is only about 20%, suggesting that immunoreactivity to the protein might be able to distinguish between infections with the EEHV1A or EEHV1B variant of EEHV1.