PIKFYVE and infection: Apilimod, the PIKfyve inhibitor used in these studies, has recently been proposed as a drug to investigate further for the treatment of COVID-19 (Kang et al., 2020; Ou et al., 2020; Riva et al., 2020), and also blocks the infection of Ebola virus in cells (Nelson et al., 2017; Qiu et al., 2018).