Children's Illnesses: Which Ones Are Contagious?

Medically Reviewed by Jennifer Robinson, MD on August 22, 2021
7 min read

Your child's best friend has developed a rash. Three classmates were sent home with the flu. It seems that everywhere you take your child, people are coughing and sneezing. When should you be concerned? What can you do?

This guide to common illnesses in children fills you in on which are and are not contagious. It also provides tips for how to keep your child healthy or get them on the road to recovery.

No wonder it's called the common cold -- the average preschool and elementary child suffers between six and 10 colds per year. Cold symptoms -- including sore throat, runny nose, cough, sneezing, and fatigue -- can last for a few days to two weeks.

How it spreads. Cold viruses reach kids via droplets in the air when a sick person coughs or sneezes. Kids also pick up colds through direct contact with sniffly friends or by touching germy surfaces -- like toys or classroom desks -- and then touching their face, especially their mouth or eyes.

Prevention. Getting your child a yearly flu vaccine is the best way to prevent the flu. You can also reduce their risk of cold or flu by teaching them to wash their hands frequently with soap and warm water. Children should also learn to avoid close contact and sharing food and utensils with other people. They also need to avoid putting their hands and other non-food items in their mouth.

Treatment. While there's no cure for a cold, you can make your child more comfortable when they have one. Give them acetaminophen for pain and plenty of fluids. Salt water gargles can ease a sore throat and steam helps clear congestion. If cold symptoms are accompanied by a high fever, severe muscle aches, and exhaustion, your child may have the flu. Talk to their doctor about other ways to ease symptoms.

Hand, foot, and mouth disease is a common viral illness that most often affects babies and children under age 5. Symptoms include fever, mouth sores, and skin rash.

How it spreads. Viruses that cause hand, foot, and mouth disease are passed in saliva, nasal mucus, fecal matter, and fluid from mouth blisters of infected people. Your child can also catch it by touching anything touched by a person who has it.

Prevention. Frequent hand washing helps prevent the spread of hand, foot, and mouth disease. Your child should also avoid close contact or sharing food or utensils with other kids. If an infected child has been to your house, wash toys and household surfaces that may harbor the germs. Then disinfect them, using 1 tablespoon of bleach to 4 cups of water.

Treatment. There is no specific treatment for hand, foot, and mouth disease. Since it's caused by a virus, antibiotics aren't called for. But there are things you can do to help ease your child's symptoms. Give acetaminophen for pain and fever. Your doctor may recommend using analgesic mouthwashes and sprays to numb painful mouth sores. And make sure your child gets enough fluids to make sure they don't get dehydrated. If you're not sure how much they need, or if you are concerned about any of their symptoms, call the doctor.

Pink eye, or conjunctivitis, is an irritation of the eye and lining of the eyelid. Symptoms may include itching, burning, redness, increased tearing or discharge, sensitivity to light, and crusting on the lids or lashes.

How it spreads. Viruses, bacteria, allergens, or irritants can cause pinkeye. When a virus or bacteria is the cause, children can catch it easily by touching a contaminated surface and then touching their eyes.

Prevention. To protect your children and yourself, wash hands frequently with soap and warm water. When soap and water aren't available, use an alcohol-based hand sanitizer. Do not allow children to share towels, pillows, washcloths, or other items with someone who is infected. If you or someone else in your home has pinkeye, wash pillowcases, sheets, washcloths, and towels in hot water and detergent to avoid spreading it.

Treatment. Mild conjunctivitis often gets better on its own. Artificial tears and cold packs can help relieve dryness and inflammation. If your child has eye pain, fever, vision problems, headache or intense redness, or they are not better within a couple of days, call their doctor. They may need prescription medication.

"Stomach flu" isn't actually the flu (influenza) but gastroenteritis, an upset stomach usually caused by a virus. Symptoms may include abdominal pain, cramps, diarrhea, fever, and vomiting. They can also include a rash. They usually improve within a few days.

How it spreads. Your child can get gastroenteritis through close contact with someone who has it or by eating food that's been prepared or touched by someone who has it.

Prevention. Try to keep your child away from people who have the stomach flu. Teach them to wash their hands frequently, particularly before eating and after using the bathroom. Teach your child to avoid sharing foods and utensils with other kids. Teach them not to put their fingers in their mouth.

Treatment. There is no specific treatment for stomach flu. Give your child popsicles and extra clear fluids to make sure they stay well hydrated. They should also rest. Avoid spicy foods and fried foods. Give small amounts of bland foods like gelatin, toast, crackers, rice, or bananas at first. You may even consider adding a probiotic to increase the healthy and normal bacteria in their gut. Then go back to their regular diet, but feed them small amounts frequently. If you think your child is not drinking enough or voiding enough (a child 1 or older needs to void at least once every four hours) call your doctor. If your little one is less than 1 and has vomiting or diarrhea, consult your doctor.

This viral illness usually affects school-age children, most commonly in winter and spring. It usually begins with low-grade fever, headache, and stuffy or runny nose. But the primary symptom is a bright red rash that starts on the cheeks -- giving the appearance of slapped cheeks -- and can progress to the trunk, arms, and legs.

How it spreads. Parvovirus B19, which causes fifth disease, is spread through saliva, sputum, and nasal mucus.

Prevention. Fifth disease is most contagious in the "stuffy nose" phase, before the rash begins, so it is difficult to prevent. Your child's best defense is to avoid contact with children who are coughing and sneezing. Frequent hand washing -- especially before touching their eyes, nose, or mouth - also helps.

Treatment. Fifth disease is usually mild and requires no treatment other than rest. If needed, acetaminophen or anti-itch medication may help relieve symptoms. However, parvovirus B19 can cause serious complications in people with a weakened immune system or chronic anemia, or in women who are pregnant. Then it's important to see a doctor.

Eczema, or "atopic dermatitis," affects about one in 10 babies and children. Symptoms can begin before a child's first birthday and almost always by age 5. Eczema begins as an itchy rash on the face, elbows, or knees that may spread to other areas including the scalp and behind the ears. The rash may get better and even go away at times, but it keeps coming back.

Cause. Genes and environmental factors -- such as foods, pollen, dust, animal dander -- are believed to cause eczema. Kids with eczema have an increased risk of having allergies and asthma.

Prevention. You can't keep your child from getting eczema, but you can help prevent it from flaring. Dry skin is a trigger, so moisturize your child's skin often, especially after baths. Have them wear soft clothes in fabrics that "breathe" such as cotton. Avoid perfumed soaps or lotions as well as bubble baths because they can irritate the skin. Also don't overuse soap because it  can dry out the skin. Oatmeal baths may help prevent flares. Recognize signs of skin infection and treat them early.

Treatment. Cool baths can help relieve itching. Your child's doctor may have other advice and prescribe treatment, if necessary. This may include corticosteroid creams or ointments, topical medications, tar preparations, antihistamines to relieve itching, and oral or topical antibiotics for infections that can accompany flares.

Most children have at least one middle ear infection by age 2. Colds or allergies can cause bacteria to grow in a child's middle ear, blocking the eustachian tubes, which connect the middle ear to the throat. This may cause pain, fever, and sometimes, difficulty hearing.

Cause. Although children can't catch ear infections from other children, they can catch colds, which make ear infections more likely.

Prevention. To reduce the risk of ear infections, help your child keep a healthy distance from people who are sick, and wash their hands frequently. Avoid exposing them to cigarette smoke, which can increase the risk of ear infection. And do not let them drink bottles while lying down.

Treatment. If your child has pain and fever from an ear infection, give acetaminophen to make them comfortable and see a doctor. They may need antibiotics, although many ear infections go away on their own in children older than 2 years of age. Most ear infection symptoms go away in a few days after antibiotics are started.