Medical cases have proved that raising pigeons or frequent close contact are prone to cryptococcal pneumonia  Cryptococcus may not only exist in pigeon feces, but also spread through the air  in addition, frequent contact with Cryptococcus carriers may also be caused by infection  At the same time, there are healthy carriers of Cryptococcus
Xiao Zhang suffered from acute pneumonia and was diagnosed by the doctor as cryptococcal pneumonia
Xiao Zhang never comes into contact with sick people, so if his disease is not infected by Cryptococcus in pigeon feces, it must have been airborne