Doctor's Notes on Upper Respiratory Infection
An infection of the upper respiratory tract can occur in the sinuses, nasal passages, pharynx, and larynx. Most cases of upper respiratory infection are caused by viruses, such as the common cold, and go away on their own with time. Infection with the influenza virus is another type of upper respiratory infection. Less commonly, bacterial infections like whooping cough or group A streptococcus (“strep throat”) may cause infections of the upper air spaces.Depending on the site of the infection, upper respiratory infections can cause sore throat, runny nose, nasal congestion, inflammation of the tonsils, sinus headache, cough, and sneezing. Other possible associated symptoms can include fever, chills, lethargy, fatigue, loss of voice or hoarseness, enlarged lymph nodes in the neck, watery eyes, bad breath, and body aches.
Upper Respiratory Infection Symptoms
Symptoms of the common cold may include:
- stuffiness (nasal congestion), runny nose, low grade fever, post-nasal drip, and cough;
- the cough is usually dry (no sputum from the lung is being produced);
- with post-nasal drip, the cough may bring up some of the nasal secretions that have dripped into the back of the throat; and
- sinusitis symptoms such as fullness in the face, increased nasal drainage, and occasionally pain and fever;
In some infants and children, the upper airways may become inflamed causing croup (laryngotracheobronchitis, acute LTB). In addition to runny nose and stuffiness, the upper airways, especially the larynx can become inflamed causing a croupy or "barking cough."
Upper Respiratory Infection Causes
People "catch" colds when they come into contact with airborne viruses. Most often, the virus spreads from person to person in respiratory droplets from sneezing or coughing. Transmission of viruses can also occur due to poor hand washing techniques An infected person may shed viral particles onto their hands and then pass on these particles to someone else through a handshake or by handing them an object such as a pen or credit card. The second person then touches their own nose, eyes or mouth, thereby acquiring the virus. Some viruses can live on surfaces such as sink faucets, door and drawer handles, table surfaces, pens, and computer keyboards for up to two hours, providing another way of spreading the infection.
People should understand that upper respiratory infections are contagious and are spread from person to person. Individuals are infected with the virus before symptoms arise and are therefore potentially contagious even before they know they are ill. Thus, hygienic measures such as covering sneezes and coughs, and regular hand washing should be a routine habit practiced by everyone even when not ill.
Rhinovirus ("rhino" from the Greek word for nose) and coronavirus are the two most common viruses causing upper respiratory infections. Other viruses including parainfluenza virus, respiratory syncytial virus, and adenovirus can cause colds but may also cause pneumonia, especially in infants and children.
The body’s respiratory system includes the nose, sinuses, mouth, throat (pharynx), voice box (larynx), windpipe (trachea), and lungs. Upper respiratory infections affect the parts of the respiratory tract that are higher on the body, including the nose, sinuses, and throat, while lower respiratory infections affect the airways and lungs.
Upper Respiratory Infection
Types of upper respiratory infection include the common cold (head cold), the flu, tonsillitis, laryngitis, and sinus infection. Of the upper respiratory infection symptoms, the most common is a cough. Other symptoms of upper respiratory infection may include stuffy or runny nose, sore throat, sneezing, muscle aches, and headache.
Lower Respiratory Infection
Lower respiratory infection can be caused by bronchitis, pneumonia, respiratory syncytial virus (RSV), severe flu, or tuberculosis, for example). Lower respiratory infection symptoms include a severe cough that may produce mucus (phlegm), cause shortness of breath, chest tightness, and wheezing when exhaling.
Cold & Flu : Influenza vs. Common Cold QuizQuestion
Which illness is known as a viral upper respiratory tract infection?See Answer
Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.