Merck Manual

Please confirm that you are not located inside the Russian Federation

honeypot link

Overview of Viral Respiratory Tract Infections in Children


Brenda L. Tesini

, MD, University of Rochester School of Medicine and Dentistry

Reviewed/Revised Jun 2023 | Modified Sep 2023
Topic Resources

Viral respiratory tract infections affect the nose, throat, and airways and may be caused by any of several different viruses.

  • Common respiratory tract infections include the common cold and influenza.

  • Typical symptoms include nasal congestion, a runny nose, scratchy throat, cough, and irritability.

  • The diagnosis is based on symptoms.

  • Treatment aims to relieve symptoms.

  • Good hygiene is the best way to prevent these infections, and routine vaccination can help prevent influenza.

Children develop on average six viral respiratory tract infections each year.

Viral respiratory tract infections are typically divided into

Children sometimes have infections involving both the upper and lower respiratory tracts.

Did You Know...

  • Becoming chilled, wet, or tired does not cause a cold or make a child more likely to catch a cold.

Causes of Viral Respiratory Infections

Many different viruses Overview of Viral Infections A virus is composed of nucleic acid, either DNA or RNA, surrounded by a protein coat. It requires a living cell in which to multiply. A viral infection can lead to a spectrum of symptoms from... read more infect the respiratory tract. In children, rhinoviruses, influenza viruses Influenza (Flu) Influenza (flu) is a viral infection of the lungs and airways with one of the influenza viruses. It causes a fever, runny nose, sore throat, cough, headache, muscle aches (myalgias), and a general... read more (during annual winter epidemics), parainfluenza viruses, respiratory syncytial virus Respiratory Syncytial Virus (RSV) Infection and Human Metapneumovirus Infection Respiratory syncytial virus infection and human metapneumovirus infection cause upper and sometimes lower respiratory tract infections. Respiratory syncytial virus is a very common cause of... read more (RSV), enteroviruses Overview of Enterovirus Infections Enteroviruses are a group of viruses. Enterovirus infections affect many parts of the body and may be caused by any of several different viral strains. Enterovirus infections may be caused by... read more Overview of Enterovirus Infections , coronaviruses Coronaviruses and Acute Respiratory Syndromes (MERS and SARS) Coronaviruses are a large family of viruses that cause respiratory illness ranging in severity from the common cold to fatal pneumonia. There are many different coronaviruses. Most of them cause... read more , and certain strains of adenovirus are the main causes of viral respiratory infections.

Most often, viral respiratory tract infections spread when children's hands come into contact with nasal secretions from an infected person. These secretions contain viruses. When the children touch their nose or eyes, the viruses gain entry and produce a new infection. Less often, infections spread when children breathe air containing droplets that were coughed or sneezed out by an infected person.

For various reasons, nasal or respiratory secretions from children with viral respiratory tract infections contain more viruses than those from infected adults. This increased output of viruses, along with typically lesser attention to hygiene, makes children more likely to spread their infection to others. The possibility of transmission is further enhanced when many children are gathered together, such as in child care centers and schools. Contrary to what people may think, other factors, such as becoming chilled, wet, or tired, do not cause colds or increase a child's susceptibility to infection.

Symptoms of Viral Respiratory Infections

When viruses invade cells of the respiratory tract, they trigger inflammation and production of mucus. This situation leads to nasal congestion, a runny nose, scratchy throat, and cough, which may last up to 14 days. Some children may continue to cough for weeks after the upper respiratory infection has resolved. Fever, with a temperature as high as 101 to 102° F (about 38.3 to 38.9° C), is common in young children or those with influenza. The child's temperature may even rise to 104° F (40° C).

Other typical symptoms in children include decreased appetite, lethargy, and a general feeling of illness (malaise). Headaches and body aches develop, particularly with influenza. Infants and young children are usually not able to communicate their specific symptoms and just appear cranky and uncomfortable.

Complications of viral respiratory tract infections

Because newborns and young infants prefer to breathe through their nose, even moderate nasal congestion can create difficulty breathing. Nasal congestion leads to feeding problems as well because infants cannot breathe while suckling from the breast or bottle. Because infants are unable to spit out mucus that they cough up, they often gag and choke.

The small airways of young children can be significantly narrowed by inflammation and mucus, making breathing difficult. Children breathe rapidly and may develop a high-pitched noise heard on breathing out (wheezing Wheezing in Infants and Young Children Wheezing is a relatively high-pitched whistling sound that occurs during breathing when the airways are partially blocked or narrowed. Wheezing is caused by a narrowing of the airways. Other... read more ) or a similar noise heard on breathing in (stridor Stridor Stridor is a gasping sound during inhalation resulting from a partial blockage of the throat (pharynx), voice box (larynx), or windpipe (trachea). Stridor is usually loud enough to be heard... read more ). Severe airway narrowing may cause children to gasp for breath and turn blue (cyanosis Cyanosis Cyanosis is a bluish or grayish discoloration of the skin resulting from an inadequate amount of oxygen in the blood. Cyanosis occurs when oxygen-depleted (deoxygenated) blood, which is bluish... read more ). Such airway problems are most common with infection caused by parainfluenza viruses, RSV, and human metapneumovirus infection Respiratory Syncytial Virus (RSV) Infection and Human Metapneumovirus Infection Respiratory syncytial virus infection and human metapneumovirus infection cause upper and sometimes lower respiratory tract infections. Respiratory syncytial virus is a very common cause of... read more . Children who are gasping or have cyanosis need to be seen urgently by a doctor.

Diagnosis of Viral Respiratory Infections

  • A doctor's evaluation

Doctors and parents recognize respiratory tract infections by their typical symptoms. Generally, otherwise healthy children with mild upper respiratory tract symptoms do not need to see a doctor unless they have trouble breathing, are not drinking, or have a fever for more than a day or two.

X-rays of the neck and chest may be taken in children who have difficulty breathing, stridor, or wheezing or if the doctor can hear congestion in the lungs.

Blood tests and tests of respiratory secretions are rarely helpful.

Treatment of Viral Respiratory Infections

  • Rest and fluids

  • Medications for fever and pain

Antibiotics are not given because they cannot cure viral respiratory tract infections.

Children with respiratory tract infections need additional rest and adequate fluid intake. Acetaminophen or nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, can be given for fever and aches.

In infants and young children, congestion may be relieved somewhat by using a cool-mist vaporizer to humidify the air and by suctioning the mucus from the nose with a rubber suction bulb.

There are antiviral drugs for influenza Antiviral drugs Influenza (flu) is a viral infection of the lungs and airways with one of the influenza viruses. It causes a fever, runny nose, sore throat, cough, headache, muscle aches (myalgias), and a general... read more that can be used in children. However, these drugs work only if taken within the first day or two after symptoms begin, and they shorten the duration of fever and symptoms only by a day or so and are not often used in otherwise healthy children.

School-aged children may take a nonprescription (over-the-counter) decongestant for bothersome nasal congestion, but they often do not help. Infants and young children are particularly sensitive to the side effects of decongestants and may develop agitation, confusion, hallucinations, lethargy, and rapid heart rate, so they should never be given decongestants.

Prevention of Viral Respiratory Infections

  • Good hygiene

  • Vaccination for influenza

The best preventive measure is practicing good hygiene. An ill child and the people in the household should wash their hands frequently. In general, the more intimate physical contact (such as hugging, snuggling, or bed sharing) that takes place with an ill child, the greater the risk of spreading the infection to other family members. Parents must balance this risk with the need to comfort an ill child. Children should stay home from school or child care facilities until the fever is gone and they feel well enough to attend.

Influenza Influenza (Flu) Influenza (flu) is a viral infection of the lungs and airways with one of the influenza viruses. It causes a fever, runny nose, sore throat, cough, headache, muscle aches (myalgias), and a general... read more and COVID-19 COVID-19 COVID-19 is an acute respiratory illness that can be severe and is caused by the coronavirus named SARS-CoV-2. Symptoms of COVID-19 vary significantly. Two types of tests can be used to diagnose... read more are preventable by vaccination. All people 6 months of age and older should receive yearly influenza vaccination (see also Influenza Vaccine Influenza Vaccine The influenza virus vaccine helps protect against influenza. Two types of influenza virus, type A and type B, regularly cause seasonal epidemics of influenza in the United States. There are... read more ). All people 6 months of age and older should remain up to date on COVID-19 vaccination according to current vaccination schedules COVID-19 Vaccine Coronavirus disease 2019 (COVID-19) vaccines provide protection against COVID-19. COVID-19 is the disease caused by infection with the SARS-CoV-2 virus. There are multiple COVID-19 vaccines... read more (see also the CDC's Interim Clinical Considerations for Use of COVID-19 Vaccines Currently Approved or Authorized in the United States). Vaccination is particularly important for children and adults who have certain disorders, such as heart or lung disease (including cystic fibrosis and asthma), diabetes, kidney failure, and sickle cell disease. Additionally, children who have a weakened immune system, including children with human immunodeficiency virus (HIV) infection and those undergoing chemotherapy, should receive the vaccine.

More Information

The following English-language resource may be useful. Please note that THE MANUALS is not responsible for the content of this resource.

Drugs Mentioned In This Article

Generic Name Select Brand Names
7T Gummy ES, Acephen, Aceta, Actamin, Adult Pain Relief, Anacin Aspirin Free, Aphen, Apra, Children's Acetaminophen, Children's Pain & Fever , Children's Pain Relief, Comtrex Sore Throat Relief, ED-APAP, ElixSure Fever/Pain, Feverall, Genapap, Genebs, Goody's Back & Body Pain, Infantaire, Infants' Acetaminophen, LIQUID PAIN RELIEF, Little Fevers, Little Remedies Infant Fever + Pain Reliever, Mapap, Mapap Arthritis Pain, Mapap Infants, Mapap Junior, M-PAP, Nortemp, Ofirmev, Pain & Fever , Pain and Fever , PAIN RELIEF , PAIN RELIEF Extra Strength, Panadol, PediaCare Children's Fever Reducer/Pain Reliever, PediaCare Children's Smooth Metls Fever Reducer/Pain Reliever, PediaCare Infant's Fever Reducer/Pain Reliever, Pediaphen, PHARBETOL, Plus PHARMA, Q-Pap, Q-Pap Extra Strength, Silapap, Triaminic Fever Reducer and Pain Reliever, Triaminic Infant Fever Reducer and Pain Reliever, Tylenol, Tylenol 8 Hour, Tylenol 8 Hour Arthritis Pain, Tylenol 8 Hour Muscle Aches & Pain, Tylenol Arthritis Pain, Tylenol Children's, Tylenol Children's Pain+Fever, Tylenol CrushableTablet, Tylenol Extra Strength, Tylenol Infants', Tylenol Infants Pain + Fever, Tylenol Junior Strength, Tylenol Pain + Fever, Tylenol Regular Strength, Tylenol Sore Throat, XS No Aspirin, XS Pain Reliever
Advil, Advil Children's, Advil Children's Fever, Advil Infants', Advil Junior Strength, Advil Migraine, Caldolor, Children's Ibuprofen, ElixSure IB, Genpril , Ibren , IBU, Midol, Midol Cramps and Body Aches, Motrin, Motrin Children's, Motrin IB, Motrin Infants', Motrin Junior Strength, Motrin Migraine Pain, PediaCare Children's Pain Reliever/Fever Reducer IB, PediaCare Infants' Pain Reliever/Fever Reducer IB, Samson-8
quiz link

Test your knowledge

Take a Quiz!