Chickenpox is a highly contagious disease caused by a virus.

The most common symptom of chickenpox is a rash that turns into itchy, fluid-filled blisters and then scabs. The rash usually shows up on the face, chest, and back first and then spreads to the rest of the body.

Other signs and symptoms of chickenpox may include:

Fever

Tiredness

Loss of appetite

Headache

What you may see: Tiny bumps on the skin can appear when your child’s skin becomes irritated or infected. If the bumps fill with pus, they can look white. These bumps tend to form on skin covered by clothing, such as the buttocks or thighs.

Is it contagious? No.

Is treatment needed? When you avoid what’s causing the bumps, folliculitis generally clears on its own. In babies and children, the cause is often tight clothing.

What you may see: Very common in children, this disease usually causes spots to develop on the fingers, palms, or soles. These spots quickly turn into bumps or blisters. You may also see spots in your child’s mouth or small blisters in the back of your child’s throat.

Contagious: Yes. A virus causes hand, foot, and mouth disease (HFMD). Most people get HFMD by 5 years of age.

Is treatment necessary? HFMD tends to clear on its own without treatment in 7 to 10 days. If your child gets HFMD before 2 years of age, it can take longer for your child to feel better.

It’s important to keep your child at home while your child has bumps and blisters and symptoms, such as fever. This helps your child recover and prevent spreading the disease to other children. At-home treatment can help relieve symptoms, such as painful mouth sores and fever.

Babies and young children have a higher risk of getting heat rash than adults. The rash appears suddenly, and you’ll see small bumps and discoloration, such as redness. Heat rash is also called “prickly heat” because the skin may feel itchy or prickly.

Contagious: No.

Is treatment needed? If your child has a heat rash, take your child to a cool place.

These raised, itchy bumps often develop when your child has an allergic reaction. Hives can also be brought on by cold temperature, water, pressure on the skin, or another cause.

Contagious: No.

Is treatment necessary? Hives tend to appear and clear within a few hours. Your child may get hives once and never again. It’s also possible to have many flare-ups. If your child continues to get hives daily or almost every day for six weeks or longer, your child has a condition called chronic hives. Getting relief often requires medical help.

Also known as “school sores,” you may see raw sores or blisters around your child’s mouth, nose, or both. As impetigo progresses, the bumps often become covered in a thick, yellowish-brown crust.

Contagious: Yes.

All types of impetigo are very contagious. It is caused by a bacteria. Most people get impetigo through skin-to-skin contact with someone who has it. It’s also possible to get it by using something infected with the bacteria.

Is treatment needed? Yes. To cure this infection, a child usually needs an antibiotic that you apply to your child’s skin, along with proper skin care.

If your child has tiny, rough, and dry bumps scattered along the upper arms, thighs, cheeks, back, or buttock, your child may have keratosis pilaris (KP). It’s common in children and teens and can worsen during puberty.

Contagious: No.

Is treatment necessary: No. This condition is completely harmless. Dermatologists offer treatment to teenagers and adults who dislike the way KP makes their skin look.

Many people get lichen planus. This disease can develop on one or several parts of the body. It can appear on the skin or inside the mouth. Sometimes, it appears in both places. Lichen planus can even change the way a person’s fingernails or toenails look. It also can appear on the genitals or a person’s scalp.

Lichen planus is not contagious. You cannot get this disease from someone else, and you cannot give it to anyone. Lichen planus is not a type of cancer.

Lupus is a group of diseases that can cause inflammation in different parts of your body. One part of the body that lupus often affects is the skin. When lupus affects the skin, it’s called cutaneous (skin) lupus. Board-certified dermatologists are experts in treating cutaneous lupus.

Is cutaneous lupus contagious? No. In fact, no type of lupus is contagious.

Butterfly Rash of Lupus

If you have a butterfly rash, lupus may be affecting more than your skin. A board-certified dermatologist can tell you.

Lupus can affect the skin in many ways. Some ways that it appears on the skin include:

A widespread rash on your back

A butterfly-shaped rash on your face

Thick, scaly patches on your face

Sores inside your mouth or nose

A flare-up on your skin that looks like a sunburn

Sometimes, the rashes, sores, and other lesions burn or itch.

Caused by a virus, this condition causes fleshy little bumps on the skin. When the bumps first appear, you usually see ones that are small, firm, and pink, flesh-colored, or white. With time, these bumps often grow.

Contagious: Yes. Because this condition is contagious and tends to last for months, it’s important to take precautions to prevent your child from spreading the virus to you and others.

Is treatment necessary: Some children need treatment; others don’t. A board-certified dermatologist can tell you which is recommended for your child.

When a child has a healthy immune system, dermatologists often recommend letting the disease clear on its own. Clearing can take time. You may see new bumps for several months. As some bumps clear, new ones can appear. This cycle usually lasts about 6 to 18 months before the skin clears completely.

Common in children and young adults, the first sign of this disease is often a large oval patch on the skin. Many smaller patches or tiny bumps appear later. Sometimes, only bumps appear on the skin.

Contagious: Pityriasis rosea is not thought to be contagious.

Is treatment needed? The rash will clear on its own, so it’s usually nothing to worry about. Still, it’s important to get diagnosed. It’s possible that the rash could be something other than pityriasis rosea.

If you have ringworm, you may think you have worms in your skin or a disease caused by worms. You have neither. Ringworm is actually a skin infection caused by fungus. No worms involved.

The name “ringworm” probably comes from the rash that many people see. On the skin, the rash often has a ring-shaped pattern and a raised, scaly border that snakes its way around the edge like a worm.

Ringworm is common. You’ve already had it if you had:

Athlete’s foot

Jock itch

Scalp ringworm

Ringworm can appear on just about any part of your body. On the palms, soles, scalp, groin, and nails, the rash lacks the ring-shaped pattern.

No matter where ringworm appears on the body, treatment is important. Without treatment, the rash tends to grow slowly and cover a larger area. You can also infect other areas of your body.

Treatment can get rid of the ringworm and stop the itch, which can be intense. Because ringworm is contagious, treatment can also prevent you from spreading it to others.

Small, pus-filled bumps on the soles, palms, or both are often a sign of scabies in infants and young children. Some children develop widespread scabies, so bumps cover most of the body.

Contagious: Yes.

Is treatment needed? Yes. The person diagnosed with scabies and everyone who has had close contact with that person need treatment. The medicine used to treat scabies is only available with a doctor’s prescription.

Most people who get this disease develop a painful, blistering rash.

Is it contagious? Yes, but you cannot give anyone shingles. While you have blisters, you can spread a virus. If that virus infects someone who hasn't had chickenpox (or the chickenpox vaccine), the person can get chickenpox.

Because you are contagious while you have shingles blisters, it’s extremely important to keep the rash covered and stay away from:

Pregnant women

Babies younger than 12 months

Anyone who is sick, especially with cancer or AIDS

Everyone who has not had chickenpox

If you had chickenpox, the virus that caused it is still inside your body. When the chickenpox cleared, the virus moved from your skin to your nerves. Should this virus travel back to your skin, you will get shingles instead of chickenpox.

If you have a blistering rash, you want to see a doctor as soon as possible. Should you have shingles, starting prescription medication within 2 to 3 days of developing the rash can dramatically:

Reduce your symptoms, such as pain

Lessen the amount of time you have shingles

Lower your risk of developing other health problems, such as a condition called postherpetic neuralgia, which is pain that can linger for months or years after the rash clears

If you’ve had the rash for longer than 2 or 3 days, it’s still important to see a doctor. Shingles can lead to other health problems aside from long-lasting pain. For example, when the shingles rash develops on your face, it can affect your eyesight. Treatment can save your eyesight.

A few people who get shingles develop pneumonia, hearing loss, or a disease that causes the brain to swell (encephalitis). It’s important to find signs of these early, so that you can receive treatment.

When you see your doctor, you may hear the medical term “herpes zoster.” This is the medical name for shingles.