Anatomy of a Respiratory Tract Infection
People sometimes mistakenly think that all respiratory tract infections are alike. For example, consider the common cold. Each year, an estimated one billion cases of colds are reported in the U.S. But no matter how prevalent this virus might be, it’s far from the only explanation for a sore throat or runny nose.
“Respiratory tract infection” describes any infectious illness that starts in the respiratory system—the part of the body that helps you breathe. The system includes the sinuses, throat, airways, and lungs. Respiratory infections are typically categorized as either an upper respiratory tract infection or a lower respiratory tract infection.
Upper Respiratory Tract Infection
This condition affects the sinuses and the throat. Common upper respiratory infections include:
- A cold
- Pharyngitis or a sore throat
- Sinusitis, also known as a sinus infection
Most upper respiratory tract infections are caused by a virus or bacteria, often spread through contact with somebody sick or by touching a contaminated surface. Anyone can catch these illnesses, but children, older adults, and immunocompromised people have a higher-than-average risk of becoming ill and developing more distressing symptoms.
Lower Respiratory Tract Infection
This condition is often more serious, as it impacts the airways and lungs and impedes breathing. Lower respiratory tract infections include:
- Influenza, also known as the flu
- Bronchitis
- Pneumonia
Mild lower respiratory tract infections are usually forewarned by a cough, which may be accompanied by the expulsion of mucus. Some people also report other physical symptoms, such as a tightness in their chest, chills, or a fever.
Children, older adults, and smokers all share a higher risk for complications from lower respiratory tract infections.
Most Common Types of Respiratory Infections
While upper and lower respiratory tract infections affect different parts of the respiratory system, many people experience similar symptoms including, but not limited to:
- Sore throat
- Runny nose
- Congestion
- Coughing or sneezing
- Fatigue and lethargy
- Fever
- Muscle and body aches
Since the symptoms of respiratory tract infections are often vague, self-diagnoses aren’t always accurate. In some cases, symptoms that seem mild and characteristic of the common cold—like a sore throat or runny nose—can escalate without warning into a more severe problem that may not respond to bed rest and over-the-counter medication.
Here’s more detail about what symptoms to watch for with each type of illness and when to make an appointment with Core Medicine of Idaho or walk into our urgent care clinic.
Common Cold
Most people catch this virus from another person or from a contaminated surface. Symptoms—which could include a runny nose, cough, or mild fever—typically develop anywhere between one and three days after exposure.
Usually, there’s no reason to visit our clinic for a cold, as home care remedies—such as getting additional rest, staying hydrated, and using a saline rinse to ease congestion—help manage symptoms. However, you might need medical attention if they don’t improve or worsen after a few days.
Pharyngitis
A sore throat is inflammation of the back walls of the throat, the tonsils, and parts of the tongue. Pharyngitis is usually caused by a viral or bacterial infection but can also develop due to seasonal allergies or acid reflux.
Patients with sore throats often report muscle pain and fatigue. In some rare cases, the lymph nodes can swell, too. Complications are rare, but certain types of bacterial pharyngitis might spread outside the respiratory system to other parts of the body.
Sinusitis
This condition presents as swelling or inflammation of the sinuses—four pairs of empty cavities inside the skull that produce mucus and filter out dust, allergens, and environmental pollutants. A sinus infection can be caused by another condition—like the common cold—or develop after regular exposure to pollen or smoke.
People with sinusitis often experience symptoms such as stuffy nose, mucus drainage, and pain around their nasal passages. If the condition becomes chronic—lasting longer than three months—polyps might develop inside the nose, which prompts additional problems.
Influenza
The flu is a highly contagious nose, throat, and lung infection. Flu symptoms—a headache, persistent cough, fatigue, sore throat, and even eye pain—are sometimes confused with those of the common cold. However, influenza-related symptoms are usually more intense and often accompanied by a mid-range fever, muscle aches, and chills.
Bronchitis
This condition develops when the bronchial tubes—which transport air to and from the lungs—are irritated and inflamed. Many bronchitis cases extend from other viral infections. Symptoms, like a cough or excessive mucus production, usually improve within about a week—but, if they worsen or refuse to disappear within three weeks, you may need to see one of our medical professionals.
Pneumonia
This infection creates inflammation in the air sacs of one or both of the lungs. It can be mild, severe, or even life-threatening, and poses the greatest risks of complications for children and older adults.
Most people with pneumonia have chest pain, a cough, and either fever or chills. But, unlike a cold or bronchitis, more complex pneumonia cases can cause symptoms unrelated to the respiratory system, such as nausea, vomiting, and diarrhea.
COVID-19
Novel coronavirus, or COVID-19 and its variants, can start in the upper respiratory tract before spreading to the lungs. It’s highly contagious, often transmitted through casual contact in public places. COVID symptoms vary tremendously but typically include a cough, fever, and fatigue.
Get the Right Treatment at Our Caldwell Urgent Care
You might not need professional treatment for a respiratory tract infection that only causes mild symptoms or seems likely to clear up after a few days. Most respiratory tract illnesses go away on their own, often as quickly as they come.
However, some people are more likely to suffer complications than others. Respiratory tract infections can be especially challenging conditions for:
- Infants
- Young children
- Senior citizens
- Anyone with a compromised immune system
Even healthy adults who think they can beat a bad case of the flu or suspected COVID may need help if their symptoms are severe or last longer than expected. Be on the lookout for these warning signs of a greater problem:
- A fever of 101 degrees or higher lasting more than two days.
- Shortness of breath or significant difficulty breathing.
- A painful cough that lasts longer than two weeks.
If you have concerns about a particularly unpleasant respiratory illness—even if you’re afraid it might be infectious—contact Core Medicine of Idaho to obtain the care you need right away.