The difference between upper respiratory and lower respiratory tract infections
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As cystic fibrosis (CF) causes excessive mucus production, respiratory tract infections (RTI) — such as those caused by the common cold or influenza — can be quite common and cause more severe symptoms.
On its own, CF can cause chronic symptoms such as sinus inflammation (sinusitis), shortness of breath, and cough. These symptoms can progress into serious issues, including lung collapse.
For people with CF, viral or bacterial infections can lead to lengthy respiratory illness, which is associated with a decline in lung function and a higher risk of death.
There are two types of RTIs that can affect people with CF: upper and lower.
Upper RTIs
An upper RTI happens when a virus or bacteria enter the respiratory system, and mostly affects the upper airways — namely the nose, sinuses, pharynx, larynx, and esophagus.
Causes
The common cold is, in the vast majority of cases, caused by rhinovirus. Other viruses associated with the common cold include adenovirus, parainfluenza virus, and enterovirus. Rhinovirus causes up to 80% of all respiratory infections in peak seasons.
Cold symptoms can begin as soon as 10 to 12 hours after infection, last for between seven and 10 days, and as long as three weeks. Adults can have two to three colds in a year, while children may have up to eight bouts of the common cold.
Viruses are passed from person to person through respiratory droplets or hand-to-hand contact. Children are particularly at risk, as they wash their hands less frequently, and are more likely to put their fingers into their mouth and nose.
Other causes of upper respiratory infections include the influenza virus and respiratory syncytial virus (RSV). Roughly 15% of sore throats (pharyngitis) are caused by bacteria; the most common is Staphylococcus pyogenes, a Group A streptococcus, which causes strep throat.
Symptoms
Symptoms of upper RTI can include:
- sore throat, tonsillitis (inflammation of the tonsils), laryngitis
- sinus infection (congestion, runny nose)
- sneezing, coughing
- headache
- fever
- body ache
- fatigue.
Lower RTIs
Lower RTIs involve the trachea and the lungs, including the bronchi and bronchioles and the alveoli.
Lower RTIs include bronchitis and bronchiolitis — characterized by inflammation of the bronchi and bronchioles, respectively — as well as pneumonia.
Causes
Lower RTIs can be caused by a variety of microbes, including viruses and bacteria.
There are two different types of bronchitis: acute bronchitis, which is temporary and usually occurs after the flu or a cold; and chronic bronchitis, which is far more serious. It can cause months of coughing, lasting at least three months to years.
Bronchiectasis, a common complication of CF that is caused by long-term inflammation or obstruction of the airways, can be made worse by bronchitis and pneumonia.
Pneumonia is when the small air sacs of the lungs (called alveoli) become inflamed and fill with fluid, potentially leading to respiratory failure and death, and is a complication of lung infections caused by viruses, certain bacteria, and fungi.
One study showed that people of European descent who have CF are genetically at higher risk of developing pneumonia, compared to those of African descent.
In people with CF, bacterial infections pose a particular hazard, especially those with Pseudomonas aeruginosa.
Persistent RTIs with bacteria such as Pseudomonas aeruginosa can lead to further inflammatory damage in the lungs
Symptoms
Bronchitis symptoms include:
- cough with mucus
- chest discomfort
- slight fever and chills
- fatigue
- shortness of breath.
Pneumonia symptoms include:
- cough with mucus
- chest pain when coughing
- fever and chills
- body ache
- fatigue
- shortness of breath
- confusion and disorientation
- nausea and vomiting.
Diagnosis of bronchitis and pneumonia usually starts with a healthcare professional listening to the lungs, and can include tests such as a chest X-ray, sputum tests, and pulmonary function tests.
Treatment
Treatment for upper and lower RTIs is usually directed to address the pathogenic agent and/or to help manage the symptoms. Hospitalization might be required in more severe cases.
Standard treatments for upper and lower RTIs include:
- bronchodilators used to open airways, making it easier to breathe
- antibiotics used to treat bacterial infections of the lungs
- cough medicine, to calm cough.
How to avoid getting an RTI
There are precautions that a person with CF can take to reduce the likelihood of developing an RTI. These include:
- wearing a properly fitted mask in public
- staying up to date on vaccinations against influenza, RSV, and COVID-19
- frequent hand washing
- using hand sanitizer and antimicrobial soap
- avoiding large groups of people, especially indoors.
People with CF also have to take precautions when in healthcare settings to avoid person-to-person transmission of pathogens. These measures include:
- staying 6 feet away from other people with CF
- staggered clinic appointments
- wearing a properly fitted mask
- regular pulmonary function tests.
The COVID-19 pandemic brought changes to the way healthcare is delivered to people with CF, with the move to telemedicine and remote monitoring through the use of spirometers and oximeters at a person’s home.
One study reported, however, differences in telehealth use and care perceptions by ethnicity, race, and socioeconomic characteristics among people with CF, with people of color being less likely to have had a telehealth visit from a healthcare professional.
If a person with CF or their family members have caught a virus leading to the common cold, influenza, RSV, COVID-19, or another respiratory infection, it’s important to:
- stay home, to avoid spreading it to others
- wash hands frequently or use hand sanitizer
- consult a healthcare provider if symptoms worsen.
Cystic Fibrosis News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.
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FAQs about upper and lower respiratory tract infections
Respiratory tract infections can be treated with medications, including bronchodilators and, in some cases, antibiotics. More severe cases may require treatment in hospital.
Upper respiratory tract infection symptoms can include a sore throat, tonsillitis, laryngitis, sinus infection, sneezing and coughing, headache, fever, body ache, and fatigue. Lower respiratory tract infection symptoms can range from cough with mucus, chest pain while coughing, fevers and chills, body ache, fatigue, and shortness of breath. In the case of pneumonia, symptoms can also include disorientation, along with nausea and vomiting.
Lower respiratory tract infections involve the trachea and the lungs, including the bronchi and bronchioles, and the alveoli. Bronchitis and pneumonia are two of the most common causes of lower respiratory infection.
An upper respiratory tract infection happens when a virus or bacteria enters the respiratory system, and mostly affects the upper airways, namely the nose, sinuses, pharynx, larynx, and esophagus. The common cold is one of the most frequent causes of upper respiratory infection.
On its own, cystic fibrosis (CF) can cause chronic symptoms such as excess mucus production, sinus inflammation (sinusitis), shortness of breath, and cough. In these patients, viral or bacterial infections can lead to lengthy respiratory illness, which is associated with a decline in lung function and a higher risk of death.
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