Among numerous cytokines upregulated in COVID-19, only IL-10 has tolerogenic, anti-inflammatory and anti-proliferative properties that, differently from pro-inflammatory cytokines, can be associated with eosinopaenia and lymphopaenia [3]; both early markers of COVID-19 that indicate an early IL-10 involvement in disease progression, possibly before a pro-inflammatory response [3]. This evidence concerns the gene IL10 and COVID-19.