The results showed that serum levels of PCT, CRP, IL‐1β, IL‐2, IL‐5, IL‐6, IL‐8, IL‐12p70, IL‐17, and TNF‐α were higher in COVID‐19 patients with bacterial coinfection than in the bacteria‐negative group, suggesting that the above markers may be involved in the development of bacteria coinfection in COVID‐19 patients. Here, CALCA is linked to coinfection.