Viral rashes in young children are common. A viral rash, also called a viral exanthem, is a rash that’s caused by an infection with a virus.

Nonviral rashes may be caused by other germs, including bacteria or a fungus like mold or yeast, which can also produce diaper rash or an allergic reaction.

Rashes caused by viral infections may cause reddish or pink spots over large parts of the body, such as the chest and back. Many viral rashes don’t itch.

Viral rashes are often seen on both the right and left sides of the body as opposed to one side. They also typically occur along with or shortly following other symptoms like fever, runny nose, or a cough.

Read on to learn about the types of viral rashes in babies, how to treat them, and when to seek help from a doctor.

There are many viruses that cause rashes. Some of these viruses have become less common with the widespread use of vaccinations.

Roseola

Roseola, also called roseola infantum or sixth disease, is a common childhood virus that’s mostly caused by the human herpesvirus 6. It’s most commonly seen in children under the age of 2.

Classic symptoms of roseola are:

  • a sudden, high fever (up to 105°F or 40.6°C) that can last three to five days
  • congestion and cough
  • a rose-colored rash made up of small dots that begins on the belly and then spreads to other parts of the body, usually after the fever goes away

About 15 percent of kids with roseola will experience febrile seizures due to high fever. Febrile seizures aren’t generally dangerous, but they can cause loss of consciousness or twitching movements.

Measles

Measles, also known as rubeola, is a respiratory virus. Thanks to widespread vaccination, it’s no longer very common in the United States. It can still occur in people who haven’t been vaccinated against the virus, though.

Symptoms of measles include:

  • runny or stuffy nose
  • high fever (up to or above 104°F or 40°C)
  • cough
  • red, watery eyes

Three to five days after these symptoms appear, a rash develops. The rash typically appears as flat, red spots along the hairline. These spots can later develop raised bumps and spread down the body.

Chickenpox

Chickenpox is caused by the varicella zoster virus. A vaccination for the chickenpox became available in the mid-1990s, so it’s no longer as common in the United States as it once was.

Before the vaccination was available, nearly all children had the disease by the time they were 9.

Symptoms of chickenpox include:

  • mild fever
  • blistery, itchy rash that generally starts on the torso and head. It can then spreads to other parts of the body before crusting over and healing.

Hand, foot, and mouth disease

Hand, foot, and mouth disease is typically caused by coxsackievirus A. It usually affects kids younger than 5. Adults and older kids can get it as well.

It’s characterized by:

  • fever
  • sore throat
  • blisters inside the mouth
  • flat, red spots on the palms of hands and soles of feet, and sometimes on the elbows, knees, buttocks, and genitals
  • spots that can sometimes develop blisters

Fifth disease

Fifth disease, also called erythema infectiosum, is caused by parvovirus B19. Early symptoms, which occur before the rash in most children, include:

  • low fever
  • runny or stuffy nose
  • headache
  • sometimes vomiting and diarrhea

Once these symptoms clear up, a rash develops. A child’s cheeks may become very flushed and appear as if they were slapped. The rash can have a lacey appearance as it resolves or spreads to the arms, legs, and trunk.

Rubella

Also known as German measles, rubella has been pretty much eliminated in countries with widespread vaccinations. According to the Centers for Disease Control and Prevention (CDC), fewer than 10 cases of rubella are reported in the United States each year.

Symptoms of rubella include:

  • low fever
  • red eyes
  • cough
  • runny nose
  • headache
  • swollen neck lymph nodes, usually felt as a tenderness in the area behind the ears
  • red- or pinkish-dotted rash that starts on the face and spreads to the body, which can then merge together to create a larger rash
  • itchy rash

You can also have rubella without showing any symptoms. According to the CDC, up to 50 percent of people infected with rubella have no symptoms at all.

The diseases mentioned above are spread through mucus and saliva. Some can also be spread by touching the blister fluid. These conditions are highly contagious and can easily spread among babies and young children.

The length of time you’re contagious varies depending on the infection. For many of these viruses, your child will be contagious a few days before the rash even develops. They’ll be considered contagious for a few days afterward or until the rash disappears.

In the case of chickenpox, for example, your child will be contagious until all the blisters — and there can be several hundred of them — become crusty. A child with rubella will be most contagious from a week before the rash appears to a week after.

Most of the rashes associated with childhood viral illnesses aren’t serious for your child. Sometimes, the diseases themselves can be, especially if your child is born premature or has a weakened immune system.

See your doctor if you want a definitive diagnosis of what’s causing the rash, or if you want expert guidance on how to make your child feel more comfortable.

You should also see your child’s doctor if:

  • The rash is causing pain.
  • The rash doesn’t turn white or lighten up when you apply pressure to it. Try using the bottom of a clear tumbler to gently apply pressure. If the rash remains after you press down on the tumbler, it could indicate bleeding under the skin, which is a medical emergency.
  • Your child seems very lethargic or isn’t taking breastmilk or formula, or drinking water.
  • There’s bruising with the rash.
  • Your child has a fever in conjunction with the rash.
  • The rash doesn’t improve after a few days.

To diagnose the rash, your baby’s doctor will:

  • Ask for your child’s health history, including whether or not your child has been immunized.
  • Consider the time of year. Many of the viral illnesses that cause skin rashes are more prevalent in the summer.
  • Study the appearance of the rash. A chickenpox rash, for example, will be blister-like. The rash that comes with fifth disease can have a lace pattern and look as if their cheeks were slapped.
  • Although uncommon, your doctor may order a blood test for further evaluation and to make a more definitive diagnosis.

Most viral rashes go away on their own. Because they’re caused by viruses, antibiotics won’t help speed recovery. The best thing you can do is to keep your child comfortable. Try the following:

  • Give your child a pain reliever, like acetaminophen, if approved by their doctor. They can give you guidelines on how much and how often to offer a pain reliever. Don’t give your baby or young child aspirin. It can put them at risk for a serious condition called Reye’s syndrome.
  • Bathe your child in lukewarm or cool water if they don’t have a fever. If they do have a fever, a cold bath can cause them to shiver, which can increase their internal body temperature.
  • When you wash your child, use mild soap and gently pat the skin dry. Don’t scrub the skin, which can irritate the rash.
  • Dress your child in loose-fitting clothes.
  • Encourage rest and drinking plenty of fluids.
  • Talk to your doctor about using calamine lotion or another soothing treatment for an itchy rash.
  • If the rash is itchy, keep the area covered to help prevent your child from scratching open the area, which can lead to infection.

In some cases, you won’t be able to prevent your child from being exposed to a virus. There are some things you can do to reduce their risk for exposure and infection, including:

  • Have your child immunized against diseases for which there are vaccinations, such as measles, rubella, and chickenpox.
  • Be vigilant about hygiene. Wash your own hands and your child’s hands frequently.
  • As soon as they’re old enough, around the age of 3, teach your child the proper way to cough and sneeze. Coughing and sneezing into the crook of their elbow can help reduce the spread of germs.
  • Keep your child home when they’re sick and don’t expose them to other kids until they’ve recovered.

Some viral rashes can be prevented through vaccinations.

If your child develops a viral rash, treatment usually involves managing symptoms and keeping your child comfortable until the infection runs its course. Keep them comfortable with over-the-counter pain relievers and cool baths.

The conditions that cause viral rashes are contagious, so it’s also important to keep your child home from childcare facilities or other activities where they’ll be around other kids until they’ve made a full recovery.