Figure 4From: First infection by all four non-severe acute respiratory syndrome human coronaviruses takes place during childhood Anti-S IgM positivity rates of individual HCoVs according to age group. (A) Anti-S IgM positivity rates for HCoV-229E; (B) Anti-S IgM positivity rates for HCoV-OC43; (C) Anti-S IgM positivity rates for HCoV-NL63. (D) Anti-S IgM positivity rates for HCoV-HKU1.Back to article page