Assessment of plasma IFNα identified sustained elevated levels within the RP macaque plasma compared to the TypP macaques at both 4–6 and 10–12 weeks post-infection, with 8-fold higher concentrations of IFNα in RP infants (mean 270pg/ml) compared to TyP (33 pg/ml) (Fig 7A). Here, DUSP4 is linked to infection.