However, increases in messenger RNA (mRNA) levels for replication-dependent interferon-λ1 (IFN-λ1) (Fig. 1h, top) and IFN-β (Supplementary Fig. 1c) and the antiviral molecule viperin (Fig. 1h, bottom) were not observed until 16–20 h post infection. Here, IFNL1 is linked to infection.