Respiratory tract infection

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at September 1, 2016
StartDiseasesRespiratory tract infection

When an individual has an infection in their sinuses, airways or lungs, it is a respiratory tract infection (RTI). The cause is being exposed to either a bacteria or a virus which results in a bacterial infection or viral infection, respectively. Being infected with an RTI is the most common reason most individuals visit their physician.


Definition & Facts

An RTI is defined as any type of infectious disease that is found in a person's lower respiratory tract or upper respiratory tract. There are two types of RTIs. An upper respiratory tract infection will affect a person's throat and nose as well as their sinuses. A lower respiratory tract infection will affect a person's lungs and airways.

An RTI can be transmitted or spread in a number of different ways. An upper RTI results in the common cold, acute otitis media or (ear infection), pharyngitis, acute rhinosinusitis, acute bronchitis, and more. A lower RTI could result in tracheitis, pneumonia, bronchiolitis, and others.

It's estimated that RTIs affect men and women at the same levels. Approximately 14 percent of individuals develop some form of RTI annually.

Symptoms & Complaints

An RTI is something that can happen at any time. People experience the symptoms of RTIs most often during the fall and winter months. Some of the early symptoms associated with having an RTI in the upper lungs could include fatigue, runny nose (rhinorrhea), body aches, coughing as well as a sore throat.

Should the RTI advance, an individual could also develop more serious symptoms. This includes chills and a fever as well as difficulty breathing. A person could eventually experience low blood oxygen levels, dizziness, and loss of consciousness.

The estimates of time required to recover from an RTI vary. The symptoms of an RTI will depend on what part of a person's respiratory system is affected, and if the infection is from a bacteria or virus. The level of the infection will also impact the symptoms.

The most common development from an RTI is a middle ear infection. According to the US Centers for Disease Control and Prevention (CDC) after seeing a doctor, an ear infection resulting from an RTI could take four days for recovery. An acute sore throat could take a week, and bronchitis could take as long as three weeks to run its course.


RTIs are infectious. This means it is something that can easily move from person to person. When an individual has an RTI, droplets of fluids from them contain the virus and can be launched into the air any time they cough or sneeze. A person could also become infected if someone who has an RTI touches a surface, and it is then touched by another person.

There are a number of different causes of RTIs. Adenovirus is a type of microorganism that is able to cause a person to develop an RTI. This type of virus is made up of more than 49 different types of viruses. They are known to result in pneumonia, the common cold, and bronchitis.

There is also pneumococcus. This is a form of bacterium that can causes a person to develop bacterial meningitis. It also has the ability to cause respiratory illnesses such as pneumonia.

The main cause of the common cold is rhinoviruses. The common cold is usually not complicated with most people. The exception is the very young as well as very old individuals who have a weakened immune system. In these situations, a cold can result in an acute respiratory infection.

Diagnosis & Tests

In order to confirm if a person has an RTI, a physician will examine a patient's lungs. This will be done by listening to a person's breathing. Any type of fluid or inflammation in the lungs will be noted. In early stages, an RTI will go away in a short period of time.

If the infection becomes severe, a computed tomography (CT) scan or X-ray may be needed to determine the condition of an individual's lungs. It's also possible for a physician to use pulmonary function tests as a diagnostic tool.

Another diagnostic method is pulse oximetry. This is able to determine how much oxygen is getting into a person's lungs. A physician may also ask for a sputum sample. This is the material that a person will cough up from their lungs. This will be done to determine what type of virus is responsible for causing the symptoms.

A nasal or throat swab culture will take a sample of the cells and mucus in a person's throat and nose. The sample will be tested for both virus and bacteria presence. Physicians also may request a urine sample be taken. This will help show the specific type of bacterial infection affecting a person's health.

Treatment & Therapy

The main method of treatment for a viral RTI involves symptomatic support. A person will be advised to increase their intake of fluids to address fluid loss from a loss of appetite, runny nose, fevers and more. There are currently no know herbal remedies that have shown to conclusively shorten the duration of an RTI.

Many health experts discourage doctors from using antibiotics to treat common RTIs in healthy patients, especially because many are caused by viruses. Studies have shown that using antibiotics does not significantly decrease recovery time and the overprescribing of antibiotics may contribute to antimicrobial resistance and the emergence of 'super-bugs'.

When dealing with the common cold, oral doses of a nasal decongestant can be effective for short-term relief with adults by reducing 'stuffy nose' symptoms. Decongestants are not recommended for children who are 12 years of age or younger as well as individuals with high blood pressure (hypertension).

In some situations, physicians will recommend corticosteroids to decrease inflammation in airway passage as well as reduce swelling. Over-the-counter cough medications have proven to be effective in dealing with the symptoms of an upper RTI. Honey is also effective in decreasing the severity of a cough. With young children, an inhaled epinephrine could be used. This will decrease the airway spasms in RTIs and is often used with children who have croup.

Prevention & Prophylaxis

There are a number of measures a person can take to avoid developing and RTI. Some of them seem simple, but studies have shown they are very effective when it comes to decreasing incidents of RTIs. Regularly washing hands with soap and hot water is important - especially when preparing food or after a person blows their nose.

Coughing or sneezing into a tissue then putting it in the trash is important. Everyone should cover their mouths with coughing or sneezing. This will prevent RTI bacteria from getting into the air and infecting another person. Sharing of any drinking glasses, cups or cutlery should also be avoided.