Overview
Respiratory infections are infections of the breathing system, including the nose, sinuses, throat, voice box, airways, and lungs. Examples include the common cold, influenza, COVID-19, bronchitis, and pneumonia. Some are mild and improve with rest and time, while others can become severe and need medical care.
Key Symptoms
Symptoms may include cough, sore throat, runny or blocked nose, sneezing, fever, chills, body aches, headache, and fatigue. Lower respiratory infections may also cause shortness of breath, chest discomfort, wheezing, or fast breathing. Young children, older adults, and people with weakened immune systems may show fewer typical symptoms or worsen quickly.
Causes and Risk Factors
Respiratory infections are most often caused by viruses, but some are caused by bacteria or, less commonly, fungi. They can spread through droplets in the air, close contact, or by touching contaminated hands or surfaces and then touching the face. Risk may be higher with crowding, poor ventilation, smoking or secondhand smoke exposure, chronic lung or heart disease, diabetes, weakened immunity, and not being vaccinated when vaccines are recommended.
Who Is Affected
Anyone can get a respiratory infection. They are especially common in children because their immune systems are still developing and they have close contact with others in schools or childcare settings. People at higher risk of severe illness include infants, older adults, pregnant people, and those with asthma, chronic obstructive pulmonary disease, heart disease, or immune system problems.
Prevention
Wash hands regularly, avoid touching your face with unwashed hands, and cover coughs and sneezes with a tissue or your elbow. Improve airflow by opening windows when possible and avoid close contact with people who are sick. Follow local public health advice about vaccines such as influenza and COVID-19 vaccines, and avoid smoking or exposure to tobacco smoke.
Diagnosis and Tests
A healthcare professional may ask about symptoms, recent exposures, medical history, and how long you have been unwell. They may examine breathing, oxygen levels, temperature, and listen to the chest. Depending on the situation, testing may include a nasal or throat swab for viruses, blood tests, or a chest X-ray if pneumonia or another lung problem is suspected.
Treatment Categories
Treatment depends on the cause and severity. Many mild viral infections are managed with rest, fluids, and symptom relief, while bacterial infections may sometimes need prescription treatment decided by a clinician. People with breathing difficulty, low oxygen levels, dehydration, or complications may need urgent treatment in a clinic or hospital.
When to Seek Medical Care
Seek medical care if symptoms are getting worse, last longer than expected, or include high fever, persistent chest pain, worsening cough, dehydration, or trouble eating and drinking. Infants, older adults, pregnant people, and anyone with long-term lung, heart, or immune conditions should contact a healthcare professional early if they develop significant respiratory symptoms. If you think you may have pneumonia, influenza, COVID-19, or another serious infection, medical advice is important.
When It May Be an Emergency
Get emergency help right away for severe trouble breathing, blue or gray lips or face, confusion, fainting, new inability to stay awake, severe chest pain, or signs of very low oxygen. Emergency care is also needed for infants with breathing pauses, severe chest indrawing, poor feeding, or unusual sleepiness. Rapid worsening can happen with serious infections such as pneumonia or severe viral illness.