Respiratory Infections: Symptoms, Causes, and Treatment

Medically Reviewed by Poonam Sachdev on December 03, 2023
5 min read

Respiratory infections refer to any infections of the respiratory system. They can affect your throat, sinuses, lungs, or airways. They're common for people of all ages and aren’t usually serious. But if you get them often, it could be a sign you have another health issue.

Doctors split them into two types: upper and lower respiratory infections. Upper respiratory infections affect your throat and sinuses. These include colds, sinus infections, and sore throats.

Lower respiratory infections usually last longer and are more serious. These infections affect your airways and lungs. They include bronchitis and pneumonia.

The flu can be either an upper or lower respiratory infection.

You may get repeated infections because of various factors in your environment and lifestyle, such as:

  • Contact with other infected people (especially those who are coughing or sneezing)
  • Pollen and other irritants
  • Smoking and secondhand smoke
  • Cold weather
  • Lack of sleep
  • Stress

But sometimes, frequent respiratory infections arise from more serious problems. They include:

Lung disease. People with asthma, cystic fibrosis (CF), or chronic obstructive pulmonary disease (COPD) are more likely to get respiratory infections. These infections can make the symptoms of these chronic conditions worse.

Asthma. One of the most common lung diseases, asthma affects about 262 million people all over the world. COPD is widespread as well, causing more than 3 million deaths each year.

Cystic fibrosis. It is less frequent and affects about 105,000 people globally. CF causes the mucus in the lungs to become thick and sticky. This traps bacteria and viruses in your airways leading to more infections.

Structural issues. The structure of your body can make you more prone to respiratory infections. A deviated septum (in which one of your nasal passages is smaller), nasal polyps (growths in your nasal passages), and other blockages in your airways can lead to sinus infections.

Tumors. If you have lung cancer, a tumor can cause a blockage that results in repeated respiratory infections.

Aspiration. This happens when you breathe in food, liquid, or vomit. The substance gets into your lungs and may cause pneumonia. It's more common in people who have seizures or who abuse drugs or alcohol.

Gastroesophageal reflux disease (GERD). When you have this condition, stomach acid backs up into your airways, irritating your throat and nose. Chronic cough and hoarseness are common complaints.

Alpha-1-antitrypsin (AAT) deficiency. AAT is a protein made in your liver that helps protect your lungs. If you don't have enough of this protein, you're more prone to lung damage from smoking or pollutants in the air. This can lead to lung diseases such as COPD or bronchiectasis. You might also get liver disease. AAT deficiency is more common in people of Northern European ancestry and tends to run in families.

Secondary immune deficiency. This happens when your immune system is damaged by something that affects your body, such as chemotherapy medications, bad burns, malnutrition, or HIV. A weakened immune system makes you more likely to get respiratory infections.

Primary immunodeficiency. This is when you have genetic (inherited) defects that weaken your immune system. They include T-cell and B-cell deficiencies. They’re much less common than secondary immune deficiencies. People with primary immunodeficiency often get pneumonia, bronchitis, and sinus infections.

For upper respiratory tract infections, the symptoms include:

  • Cough
  • Sneezing
  • Sore throat
  • Runny or stuffy nose
  • Headache
  • Mild fever
  • Feeling tired

In a mild lower respiratory tract infection, you might have the same symptoms. But if it gets more serious, you could also have:

  • Fever
  • Heavy cough
  • Fast breathing or difficulty breathing
  • Wheezing
  • Skin turning bluish due to lack of oxygen
  • Chest pain or tightness


Some of the risk factors for adults getting recurring respiratory infections include:

  • Smoking or exposure to secondhand smoke
  • Air pollution
  • Exposure to industrial chemicals
  • Repeated respiratory infections during childhood
  • Regular contact with children
  • Having chronic illnesses like asthma
  • Being underweight
  • Living in crowded conditions

For children, the risks of repeated respiration infections are often a result of:

  • Poor nutrition
  • Attending day care centers
  • Living in crowded conditions
  • Parents smoking
  • Inadequate breastfeeding
  • Lack of immunization
  • Exposure to air pollution (from the use of biofuels for cooking)



Most upper respiratory infections such as the cold or flu can be treated at home. Antibiotics won't usually help because most respiratory infections are caused by viruses. Here's what you can do to care for yourself:

  • Drink plenty of fluids to avoid dehydration. These can include water, juices, ginger ale, and chicken soup.
  • Take a pain killer like acetaminophen (Tylenol) or ibuprofen (Aleve).
  • Get plenty of rest.
  • Use a saline nose spray or make a saline wash to keep your nasal passages clear.
  • Take cold and cough medications. Many of them already contain acetaminophen, so be careful not to take it separately at the same time.
  • If you have a sore throat, soothe it with a gargle made of 1/4 to 1/2 teaspoon of salt dissolved in 4-8 ounces of warm water.
  • If the air is dry, use a humidifier to soothe your throat and nose passages.

Lower respiratory infections can also be treated at home with rest, fluids, and over-the-counter medications. In addition, you may need a bronchodilator inhaler if you are wheezing and short of breath. Some types of pneumonia are caused by bacteria, in which case your doctor may prescribe an antibiotic. In very serious cases, you may need to go to the hospital.

Cold and flu viruses spread easily. When someone who's ill coughs or sneezes, the droplets with the virus enter the air where someone else might inhale them. Viruses are also spread by touching objects such as a doorknob or staircase railing touched by an infected person and then touching your face. Shaking hands or hugging someone who is ill poses a risk as well. Protect yourself from these viruses by doing the following:

  • Wash your hands frequently, with soap for at least 20 seconds. You don't need antibacterial soap. Rinse under running water.
  • Make sure your kids wash their hands properly too.
  • Don't touch your face with your hands. If you've just touched someone with these germs, you're more likely to give yourself the illness.
  • Don't drink out of cups or glasses that others have used. Wash them first.
  • Get a flu vaccine.

If you're the one with the virus:

  • Cover your mouth with a tissue when you cough or sneeze. If you have no tissue, cover your mouth with an elbow rather than your hand.
  • Throw used tissues in the trash. Don't leave them lying around.
  • Wash your hands often, especially after coughing or sneezing.
  • Avoid shaking hands, hugging, or kissing others.
  • Stay home when you're sick.
  • If possible, open the windows in your home or car to decrease the amount of the virus in the air, by allowing outdoor air in.



Most respiratory infections will clear up in 1-2 weeks. Schedule an appointment with your doctor if:

  • Your symptoms get worse or last longer than 3 weeks.
  • You cough up blood.
  • You’re pregnant.
  • You’re over 65.
  • You frequently get infections and can’t pinpoint the cause.
  • You have another condition such as diabetes, cancer, or a heart, lung, or kidney condition. 
  • Your fever is over 102 F for more than 3 days.
  • You have trouble breathing.
  • Your cough is getting worse.
  • Your mucus is increasing or changing color when you cough.
  • You have very swollen glands in your jaw or neck.

Guidelines for when to get medical help are different for children depending on their age.