Mycoplasma pneumonia is caused by a mycoplasma infection, which may develop when your immunity is lowered or when you are infected by someone else. Mycoplasma is an atypical pathogen that can infect the body and cause pneumonia, which is known as mycoplasma pneumonia. When the body’s immunity declines, Mycoplasma can attack the body and spread to the lower respiratory tract causing pneumonia. For example, it may develop when you are tired and cold. Mycoplasma pneumonia is also contagious. If someone has a mycoplasma infection, he or she may spread the infection to others around them, thus causing the onset of mycoplasma pneumonia.