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Overview of Viral Infections in Children


Brenda L. Tesini

, MD, University of Rochester School of Medicine and Dentistry

Reviewed/Revised Jun 2023
Topic Resources

Most childhood viral infections are not serious and include such diverse illnesses as colds Common Cold The common cold is a viral infection of the lining of the nose, sinuses, and throat. Many different viruses cause colds. Usually, colds are spread when a person's hands come in contact with... read more , sore throat Sore Throat Sore throat is pain in the back of the throat. A sore throat can be very painful and is usually worsened by swallowing. Many people with a sore throat refuse to eat or drink. Sometimes pain... read more Sore Throat , vomiting Vomiting in Infants and Children Vomiting is the uncomfortable, involuntary, forceful throwing up of food. In infants, vomiting must be distinguished from spitting up. Infants often spit up small amounts while being fed or... read more and diarrhea Diarrhea in Children Diarrhea is a very common problem in children (see also Diarrhea in adults). Diarrhea is frequent, loose, or watery bowel movements (BMs) that differ from a child’s normal pattern. Sometimes... read more , and fever Fever in Infants and Children Normal body temperature varies from person to person and throughout the day (it is typically highest in the afternoon). Normal body temperature is higher in preschool-aged children and highest... read more Fever in Infants and Children with a rash Rashes in Children A rash is an abnormal change in the texture or color of the skin. Known causes of rashes include irritation, allergies, drugs, and bacterial, fungal, or viral infections. Rashes include redness... read more Rashes in Children . Some viral infections that cause more serious disease, such as measles Measles Measles is a highly contagious viral infection that causes various cold-like symptoms and a characteristic rash. Measles is caused by a virus. Symptoms include fever, runny nose, hacking cough... read more Measles , are less common now due to widespread immunization Overview of Immunization Immunization (vaccination) helps the body defend itself against diseases caused by certain bacteria or viruses. Immunity (the ability of the body to defend itself against diseases caused by... read more . (For adults, see also Overview of Viral Infections 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 .)

Many viral infections are so distinctive that a doctor can diagnose them based on their symptoms. A doctor usually does not need to have a laboratory identify the specific virus involved.

Many viral infections result in symptoms such as fever and body aches or discomfort. Although most children with viral infections get better without treatment, doctors sometimes treat these symptoms with acetaminophen or ibuprofen. Aspirin is not given to children or adolescents with these symptoms because it increases the risk of Reye syndrome Reye Syndrome Reye syndrome is a very rare but life-threatening disorder that causes inflammation and swelling of the brain and impairment and loss of function of the liver. The cause of Reye syndrome is... read more in those who have certain viral infections. Antibiotics cannot cure viral infections. However, there are antiviral drugs Antiviral drugs 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 available for a few viral infections such as hepatitis Overview of Hepatitis Hepatitis is inflammation of the liver. (See also Overview of Acute Viral Hepatitis and Overview of Chronic Hepatitis.) Hepatitis is common throughout the world. Hepatitis can be Acute (short-lived) read more , some herpesviruses Overview of Herpesvirus Infections Some common viral infections are caused by a group of viruses called herpesviruses. Eight different types of herpesviruses infect people: Three herpesviruses— herpes simplex virus type 1, herpes... read more , 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 human immunodeficiency virus (HIV) Human Immunodeficiency Virus (HIV) Infection in Children and Adolescents Human immunodeficiency virus (HIV) infection is a viral infection that progressively destroys certain white blood cells and makes people more vulnerable to other infections and some cancers... read more .


Some Viral Infections in Children That Cause a Rash


Incubation Period*

Contagious Period†

Site of Rash

Nature of Rash in Children

7 to 14 days

From 2 to 4 days before until 4 days after the rash appears

Starts on the face around the ears and on the side of the neck

Spreads to the trunk, arms, palms, soles, and legs

Begins a few days after fever and other symptoms and lasts 3 to 5 days

Red and flat, then becomes raised and merges into larger red areas

Mildly itchy

14 to 21 days

From 1 week before until 1 week after the rash appears

(Except in newborns, who usually continue to be contagious for many months)

Starts on the face and neck

Spreads to the trunk, arms, and legs

Begins a few days after fever and other symptoms and lasts 3 to 5 days

Similar to measles rash but not as red and does not merge to form large red areas

About 5 to 15 days


Starts on the trunk and usually spreads to the face, arms, and legs

Begins within a day after a high fever decreases and lasts for up to 3 days

Red and flat, not itchy

4 to 14 days

From before the start of the rash until the rash appears

Starts on the cheeks ("slapped-cheek" appearance)

Spreads to the arms, legs, and trunk

Begins a few days after fever and other symptoms and lasts 5 to 10 days

Red, raised, blotchy areas with lacy patterns

Can be itchy

7 to 21 days (most commonly 14 to 16 days)

2 days before the rash appears until all spots have crusted

Starts on the face and trunk

Spreads to the arms and legs

Begins 1 to 2 days after the start of fever and other symptoms and lasts 4 to 7 days

Small, red spots that become raised and form very itchy, round, blisters that then crust over

* The incubation period is the number of days between when a person becomes infected with a virus (or other infections organisms, such as bacteria) and when symptoms begin.

† The contagious period is the time period that an infected person can spread infection to others. Infections can spread during the contagious period even if people do not have symptoms.

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
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