Upper Respiratory Tract Infection

Upper respiratory tract infections are among the most common illnesses worldwide, affecting millions of people every year. While these infections can be uncomfortable and disrupt daily life, most are caused by viruses and resolve on their own with proper care and rest.

Table of contents

• What is an upper respiratory tract infection?
• Other names for this condition
• Parts of the body affected
• Signs and symptoms
• What causes upper respiratory infections
• How these infections spread
• How doctors identify the infection
• Treatment approaches
• Possible complications
• How to prevent upper respiratory infections
• What to expect during recovery

What is an upper respiratory tract infection?

An upper respiratory infection (also called URI or URTI) is an illness caused by viruses or bacteria that affects the upper part of your breathing system. This includes your nose, sinuses, throat, and voice box^[1]. These infections happen when germs enter your body, usually through your mouth or nose^[2].

Upper respiratory infections are the most common infectious disease reason for doctor visits worldwide. Despite being generally mild, they significantly affect public health by causing lost productivity and many medical visits^[2].

acute nasopharyngitis, acute coryza, common cold, URI, URTI

Other names for this condition

Upper respiratory infections go by several different names. The most common form is often called the “common cold.” Medical professionals may also refer to these infections as acute nasopharyngitis or acute coryza^[2].

Parts of the body affected

Upper respiratory infections affect the parts of your breathing system above your vocal cords^[1].

• Nose (nasal passages)
• Sinuses
• Throat (pharynx)
• Voice box (larynx)

Signs and symptoms

The symptoms of upper respiratory infections can vary depending on which part of your breathing system is affected and what caused the infection^[1].

Common symptoms include runny or stuffy nose, sneezing, cough, sore throat, headache, and feeling tired^[1]. You may also experience fever, facial pain or pressure, hoarse voice or loss of voice, wheezing, and swollen glands in your neck^[1].

Symptoms typically start one to three days after you come in contact with someone who has the infection^[2]. On average, the illness lasts seven to ten days, though coughing and nasal discharge may continue for two weeks or more even after other symptoms have gone away^[5].

In the first few days of a viral cold, nasal discharge is usually clear. It often becomes cloudy white, yellow, or green over several days, which is a normal part of viral infections and not a sign that antibiotics are needed^[5].

What causes upper respiratory infections

Viruses cause most upper respiratory infections. However, bacteria and even fungi can sometimes be responsible^[1].

The most common viral causes include common cold viruses (especially rhinovirus, which is a type of virus that frequently infects the nose and throat), influenza A and B virus (the flu), SARS-CoV-2 virus (COVID-19), and respiratory syncytial virus (RSV)^[1]. Other viruses that can cause these infections include varicella-zoster virus and herpes simplex virus^[1].

Bacterial causes are less common but include Streptococcus bacteria (like group A strep and Streptococcus pneumoniae), Haemophilus influenzae bacteria, and Moraxella catarrhalis bacteria^[1]. Certain types of fungi, such as Aspergillus and mucormycetes, can also cause upper respiratory infections, though this is rare^[1].

How these infections spread

Yes, the viruses and bacteria that cause upper respiratory infections are contagious and can spread from person to person. Fungi that cause these infections do not spread between people^[1].

These infections spread through several routes. When someone with an infection coughs, sneezes, or talks, tiny droplets containing germs are released into the air^[1]. You can also catch the infection by sharing eating or drinking items like forks, spoons, cups, or water bottles with someone who is sick^[1].

Another way infections spread is through touching objects or surfaces that have germs on them, such as doorknobs, light switches, phones, or toys, and then touching your face^[1].

You are most contagious two days before your symptoms start and remain contagious until about six days after symptoms begin. You become less contagious after you have been fever-free for 24 hours without taking fever-reducing medicine^[3].

How doctors identify the infection

Healthcare providers usually diagnose upper respiratory infections based on your symptoms and simple tests. They will ask about what symptoms you have and how long you have had them^[1].

The physical examination includes looking at your ears and throat and listening to your heart and lungs^[6]. If your symptoms are mild and tests are negative for specific infections like the flu or strep throat, you might have one of hundreds of common cold viruses that doctors don’t often test for^[1].

When needed, providers may use a nasal swab or throat culture to identify the specific cause^[1]. Sometimes they will test for common viruses like flu, COVID-19, and RSV, or perform tests for strep throat. In certain cases, chest X-rays may be done to check for bacterial infections^[6].

Treatment approaches

Most upper respiratory infections are caused by viruses and go away on their own within one to two weeks. You can usually treat your symptoms at home^[3].

If your infection is caused by a virus (like the common cold), it will usually clear up by itself. Antibiotics will not help viral infections because they only work against bacteria^[3]. If your infection is caused by bacteria (like some cases of pneumonia or strep throat), a doctor may prescribe antibiotics^[3].

For symptom relief at home, get plenty of rest and drink lots of water to help loosen mucus and make it easier to cough up^[3]. You can drink a hot lemon and honey drink to help soothe a cough, though this is not suitable for babies under one year old^[3].

If you have a sore throat, gargling with warm salty water can help, though children should not try this^[3]. Raising your head up while sleeping using extra pillows can make breathing easier and help clear your chest of mucus^[3].

Over-the-counter medications can help reduce symptoms. Pain relievers can bring down a fever and help ease a sore throat, headaches, and muscle pain^[3]. Decongestants and nasal sprays may provide relief, though there is little evidence that cough medicines and throat lozenges are very effective^[3].

Some treatments contain both pain relievers and other medicines. If you are taking these medicines separately, be careful not to take more than the recommended dose. Certain treatments are not suitable for children, babies, and pregnant women^[3].

Do not let children breathe in steam from a bowl of hot water as there is a risk of burns. Do not give aspirin to children under 16, and do not smoke as it can make your symptoms worse^[3].

Possible complications

Upper respiratory infections like colds rarely lead to complications. However, infections can sometimes cause inflammation in your lungs, leading to pneumonia^[1].

If bacterial or fungal infections are left untreated, they can travel to other parts of your body and cause serious problems. These include meningitis (infection of the membranes around the brain and spinal cord), rheumatic fever, scarlet fever, sepsis (a life-threatening response to infection), and organ damage^[1].

Children can also develop ear infections (otitis media) after upper respiratory infections. If your child develops ear pain, especially with a fever that does not go away after two days, seek medical attention^[6].

You might be at higher risk for complications if you have certain health conditions or a weakened immune system, or if you are older than 65. Newborns are also at higher risk for severe illness^[1].

How to prevent upper respiratory infections

There are several practical steps you can take to lower your risk of getting an upper respiratory infection^[15].

Stay up to date with recommended vaccinations. Talk to your doctor about what vaccines may be recommended for you and your family, including the annual flu vaccine and the pneumococcal vaccine, which helps prevent pneumonia^[3].

Practice good hygiene by washing your hands regularly and cleaning commonly touched surfaces^[15]. Cover your mouth when you cough or sneeze, and throw away used tissues immediately^[3].

Take steps for cleaner air where possible in places where people live and work^[15]. If you keep getting respiratory infections or you are at high risk, stop smoking if you smoke^[3].

To reduce the chance of passing an infection to others when you are sick, stay home and away from others. Use precautions to prevent spread, such as wearing a mask^[15].

What to expect during recovery

Most upper respiratory infections pass within one to two weeks^[3]. The illness usually lasts seven to ten days after symptoms appear^[5].

You should see a doctor if you have symptoms and you feel very unwell or your symptoms get worse, you have had a high temperature for more than three days, you cough up blood or blood-stained mucus, you have had a cough for more than three weeks, you are pregnant, you are over 65, you have a weakened immune system, or you have a long-term health condition such as heart, lung, or kidney disease^[3].

If symptoms are severe, you may have pneumonia^[3]. Contact your doctor if you develop persistent fever for more than 72 hours, fever that does not come down with pain relievers, shortness of breath, or a deepened cough in the lower chest^[6].

Most people who present with upper respiratory infections benefit from reassurance, education, and instructions for symptom treatment at home. With proper care and rest, full recovery is expected^[6].