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Respiratory Infections 101

Reviewed by: HU Medical Review Board | Last reviewed: September 2022 | Last updated: December 2023

Respiratory infections affect the nose, sinuses, throat, and airways. These infections can cause symptoms such as congestion, cough, and shortness of breath.1

For people who live with certain chronic medical conditions, respiratory infections can be dangerous. If you have breathing problems or a health condition that impacts your lungs, protecting yourself from respiratory infections is crucial. Get to know the types, signs, and symptoms of respiratory infections so you can get treated right away.1-3

Types of respiratory infections

There are 2 main types of respiratory infections: upper and lower.

Upper respiratory infections affect the sinuses and throat. This type of infection is very common. An example of an upper respiratory infection is the common cold.2

Lower respiratory infections affect the airways and lungs. These infections often are more serious and typically last longer than upper respiratory infections. An example of a lower respiratory infection is bronchitis. Bronchitis is inflammation of the lining inside your airway tubes (bronchioles).2,4

What causes respiratory infections?

Respiratory infections typically are caused by respiratory viruses. Some common viruses that can cause respiratory infections are:1,2,5

Respiratory viruses can be spread from person to person in 2 ways:1

  • Respiratory droplets in the air – When you breathe in an infected person's germs after they cough or sneeze, you could get sick.
  • Physical contact – Coming into close contact with others who are sick can lead to infection. This can also include touching objects or surfaces with the virus on them and then touching your eyes, nose, or mouth.

People can spread some respiratory viruses before they show any signs or symptoms of infection. These viruses include the flu and COVID-19.1

Symptoms of respiratory infections

The symptoms you may experience with a respiratory infection include:2

  • Cough, with or without mucus (phlegm)
  • Fever
  • Runny nose
  • Sore throat
  • Hoarse voice
  • Swollen lymph nodes
  • Fatigue

At-risk people who get a respiratory infection may have certain complications. For example, if you have asthma, a respiratory infection can make your asthma symptoms worse. An infection can also trigger an asthma attack.1

Other complications may include:1-3

  • Severe symptoms such as breathing problems, high fever, wheezing, and dizziness
  • Bronchiolitis – inflammation in the small airways of the lungs
  • Pneumonia – an infection that causes fluid to build up in the lungs
  • Congestive heart failure – when the heart cannot pump enough blood and oxygen to the rest of the body

Who is most at risk of complications?

For most people, respiratory infections will clear up on their own with plenty of rest and fluids. But some people are at increased risk of health complications.1-3

Those who are most at risk of complications from a respiratory infection are:1-3

  • Young children
  • People with certain chronic health conditions, such as:
    • Asthma
    • Chronic obstructive pulmonary disease (COPD)
    • Heart failure
    • Type 2 diabetes
  • Adults with weakened immune systems
  • Adults over the age of 65

Diagnosing respiratory infections

Diagnosing a respiratory infection starts with a visit to your doctor. They will perform a physical exam to look at your nose, ears, and throat. They will also listen to your lungs.2

If your doctor suspects you have a lung infection, they may recommend additional tests, such as:2

  • Chest X-ray
  • Computed tomography (CT) scan
  • Lung function test, which measures how well your lungs are working
  • Nasal swab
  • Throat swab
  • Sputum test, which tests the phlegm that may be present in your lungs

Treating respiratory infections

Respiratory infections will usually go away on their own. Here are some ways to manage your symptoms if you have a respiratory infection:2

  • Get plenty of rest.
  • Drink plenty of liquids to stay hydrated.
  • Take over-the-counter fever reducers and pain relievers, like ibuprofen and acetaminophen.
  • Continue to take medicines for your other health conditions, unless your doctor says otherwise.

If your symptoms last longer than 2 weeks, contact your doctor.2

Your doctor may prescribe an antiviral medicine for the flu or COVID-19. This will depend on your age, your medical history, and other factors.6,7

Because most respiratory infections are caused by viruses, antibiotics usually do not help. Antibiotics are effective only for infections caused by bacteria. Pneumococcus is an example of a bacteria that can cause respiratory infections. Infection with this bacteria can lead to serious illnesses like pneumonia or meningitis.2

If you think you may have a respiratory infection, contact your doctor. They will advise you about the treatment plan that is right for you.1,2

Preventing respiratory infections

Several vaccines that can help prevent respiratory infections are available. If you live with a chronic condition that increases your risk of a respiratory infection, take action to prevent infection.1,2

These practices can help reduce your chances of an infection and spreading a virus to others:1,2,5

  • Get vaccinated for COVID-19, the flu, pneumococcal disease, and RSV.
  • Wear a mask when out in public and around large groups of people.
  • Wash your hands often, with soap and water, for at least 20 seconds.
  • Avoid touching your eyes, nose, and mouth with unwashed hands.
  • Avoid contact with others who are sick.
  • Stay at home if you feel sick.

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