We found that a cluster enriched in complement system genes, including C1NH, C1QA/B/C, C1R/S, C3, C4A, C8B, CFB, CR1, FCN1 and MASP1 (see Table 3 for full gene names), was significantly upregulated during the first 2 weeks post infection (Figure 5A). Here, CR1 is linked to infection.