angiotensin converting enzyme 2; CD147 antigen; interleukin 6; interleukin 8; luteinizing hormone; testosterone; transmembrane protease serine 2; tumor necrosis factor; abdominal pain; coronavirus disease 2019; disease association; DNA fragmentation; DNA methylation; editorial; human; Leydig cell; male; male fertility; orchitis; oxidative stress; protein expression; scrotal pain; seminiferous tubule; Sertoli cell; sperm quality; spermatogonium; spermatozoon density; testis; testis injury