Pneumonia

Pneumonia is an infection or inflammation of the tiny air sacs in one or both lungs. The air sacs may fill with fluid or pus, making it harder to breathe and get enough oxygen. What is pneumonia like can vary widely: illness may be mild, or it may become life-threatening. Pneumonia can affect people of any age and may be caused by bacteria, viruses, fungi, or less common factors.

Pneumonia symptoms can begin suddenly or develop gradually, depending on the cause, a person’s age, and overall health. Symptoms of pneumonia in adults may interfere with normal activities, while infants and older adults may show less typical signs. Walking pneumonia symptoms are often milder, but they still deserve medical attention.

Pneumonia itself is not always contagious. However, viruses and bacteria that cause some cases can spread through respiratory droplets, close contact, or contaminated hands and surfaces. Exposure does not always lead to pneumonia; a person’s immune system, health conditions, and other risk factors also affect whether an infection develops into pneumonia.

Pneumonia risk factors can increase the chance of developing an infection or the risk of serious complications. Some factors, such as age and chronic illness, cannot be changed, while others, such as smoking and infection exposure, may be reduced. Knowing these factors can help people and clinicians plan prevention and seek care early.

Many people recover from pneumonia with appropriate care, but the illness can become serious or affect other organs. Complications are more likely in older adults, infants, people with chronic conditions, and those with weakened immunity. This is why pneumonia can sometimes be deadly and why worsening symptoms need prompt medical evaluation.

Diagnosis is based on the medical history, symptoms, physical examination, oxygen level, and tests selected according to the suspected cause and severity. A clinician may assess how quickly symptoms began, listen to the lungs, and look for signs of infection or low oxygen. Testing helps distinguish pneumonia from other causes of cough and breathing problems.

Pneumonia treatment depends on whether the cause is bacterial, viral, fungal, or another type, as well as symptom severity and the person’s overall health. Some people can recover at home with supportive care, while severe illness may require oxygen or hospital treatment. A clinician should guide the treatment plan rather than relying on self-diagnosis.

Pneumonia prevention combines recommended vaccines with steps that reduce exposure to respiratory infections. Avoiding tobacco smoke and managing chronic conditions may also lower risk or reduce the chance of severe illness. Ask a clinician which vaccines and preventive measures are appropriate for your age and health.

Many people improve with appropriate care, but recovery varies from person to person. Cough and fatigue may continue after fever and breathing improve, so recovery does not always happen all at once. How long does pneumonia last depends on the cause, severity, treatment response, and a person’s general health.