Longitudinal blood counts between 42 and 295 days after the start of anti-PD-1 treatment showed that initiation of steroid therapy on day 200 (day 1 after the onset of hepatitis) was accompanied by a dramatic rise in circulating neutrophils, as previously reported [21], with little change in lymphocyte or monocyte counts (Fig. 3a, b). This evidence concerns the gene PDCD1 and hepatitis A virus infection.