Saudi Arabia's King Salman's lung infection: What causes the condition?

Saudi Arabia's 88-year-old King Salman has been diagnosed with a lung infection and will undergo treatment with antibiotics after falling ill with a fever and joint pain, state media reported early Monday. King Salman underwent medical examinations at the Royal Clinics at Al Salam Palace in Jeddah, the Red Sea port city, the state-run Saudi Press Agency said. It was found that there was a lung infection, and the medical team decided that he should undergo a treatment programme consisting of antibiotics until the infection went away, the report said. In April, the monarch entered a hospital for medical checks and was later discharged. A lung infection affects the airways or the lung tissue itself. They are caused by various microorganisms, including bacteria, viruses, and fungi. Common types of lung infections include pneumonia, bronchitis, and bronchiolitis.

What are its symptoms?
Its symptoms can vary depending on the type of infection and its severity. However, most often, the symptoms include coughing, difficulty breathing, chest pain, fever, fatigue, and sometimes coughing up phlegm or mucus. At times, the infection can lead to respiratory failure or sepsis as well. 
What's the treatment for lung infection?
Antibiotics for bacterial infections, antiviral medications for viral infections, and supportive care such as rest, hydration, and fever management are the treatments generally prescribed for lung infections. Hospitalization may be necessary in certain cases, especially for severe infections or for those with severe health conditions.
(With PTI inputs)