Bacterial and Viral Rashes

Medically Reviewed by Renee A. Alli, MD on September 04, 2023
10 min read

Many childhood diseases have bacterial or viral causes and may come with a rash. As study continues and more and more vaccines become available, these diseases become less of a threat to your child's long-term health. However, a rash of any kind should be taken seriously and may require a trip to the doctor's office for evaluation.

A virus called varicella-zoster causes chickenpox, a very contagious disease. Although it is rarely a serious disease to otherwise healthy children, the symptoms last about 2 weeks and can make the child very uncomfortable. In addition, chickenpox can be a serious illness in people with weak immune systems, such as newborns, people on chemotherapy for cancer, people taking steroids, pregnant women, the elderly, or those with HIV. A safe and effective vaccine is now available to children ages 1 and older to prevent chickenpox. It takes up to 21 days to develop chickenpox after being exposed to the virus by inhaling infected droplets from coughs or sneezes or by coming in direct contact with the lesions on an infected person with chickenpox or from someone with shingles.

  • Symptoms
    • The symptoms of chickenpox often begins with a very itchy rash, which first appears on the scalp, chest, back and face then spreads to the rest of the body.
    • The rash begins as an area of redness with a small, superficial blister in the center. The blister eventually ruptures with some possible drainage, and the lesion will then form a crust.
    • Other associated symptoms include fever, malaise, sore throat, and red eyes. Fever and malaise may precede the rash in some cases.
  • Treatment
    • The virus is spread primarily from the mucous membranes of the nose and mouth of the child, but the rash itself is also contagious. The child remains contagious and cannot go to school or daycare until the last lesion has appeared and is fully crusted over.
    • No therapy treats chickenpox once it has begun, but your doctor can provide prescriptions and advice to help with the discomfort and the itching.
    • Never give aspirin to a child in general but especially one with chickenpox. A deadly disease called Reye's syndrome has been associated with children taking aspirin, especially if they have chickenpox. Be sure to check the contents of any other over-the-counter medications for aspirin or salicylates because these are often found mixed with over-the-counter cold medications.
    • Chickenpox can occasionally affect the cornea, the clear front portion of the eye. If your child develops chickenpox on the tip of the nose  it is usually a precursor to having the eyes infected. See your doctor immediately.
    • See a doctor immediately also if your child develops lesions in the genital regions internally or inside of the mouth.

A paramyxovirus causes the measles , which is also highly contagious. A safe and effective vaccine is available to prevent this disease, but outbreaks in people who have not been adequately vaccinated still happen.

  • Symptoms
    • The disease usually begins with nasal congestion, eye redness, swelling and tearing, cough, lethargy, and high fever. Another rash consisting of white spots inside the mouth may also develop.
    • On the third or fourth day of the illness, the child will develop a red rash on the face, which spreads rapidly and lasts about 7 days.
  • Treatment
    • Once the disease begins, no medication treats measles. However, your doctor may offer treatments to care for cough, eye symptoms, and fever. Aspirin products cannot be used as they can cause a life-threatening condition called Reye's syndrome.
    • Some children develop secondary bacterial infections of the middle ear, sinuses, lung and neck lymph nodes. These can be treated with antibiotics.  In severe cases, encephalitis may develop. 
    • Children who have measles appear quite ill and are miserable, but the illness usually gets better without lasting ill effects within 7-10 days after symptoms start.
    • You can prevent your child from getting measles by making sure they receive the recommended vaccinations. The measles vaccine is part of the MMR (measles-mumps-rubella) vaccine given at age 12-15 months and repeated at age 4-6 years.

Rubella is a much milder disease in children that's also caused by a virus (rubivirus). Symptoms may begin 14-21 days after exposure to the virus. If contracted in the womb, rubella is a much more serious disease, causing deafness, heart abnormalities, eye problems, retardation, and other conditions in the newborn.

  • Symptoms in children
    • Rubella begins with a pink/red rash on the face then spreads to the rest of the body and gets better in about 4 days.
    • Your child does not appear to be very ill but may develop swollen lymph nodes in the neck, especially behind the ears.
  • Prevention
    • Rubella is also easily prevented with an effective vaccine (the MMR).
    • Rubella can be very serious to an unborn child if the mother develops rubella early in her pregnancy. All women of childbearing age should have their immune status verified.

Scarlet fever is strep throat with a rash. The throat infection is caused by streptococcal bacteria. It is most commonly seen in school-aged children in the winter and early spring, but it can occur in individuals of any age and in any season. It is very contagious, especially from saliva transmission. The risk of transmission can be decreased with good hand washing.

The rash is not serious, but serious complications can occur from the underlying strep throat infection. The most worrisome of these is rheumatic fever, a serious disease that can damage the heart valves and cause long-term heart disease.

  • Symptoms
    • The child's symptoms begin with sore throat (which can be mild), fever, headache, abdominal pain, and swollen glands in the neck.
    • After 1-2 days of these symptoms, the child develops a rash on the body that is red like sunburn and has a sandpaper texture. The skin folds in the neck, armpits, elbows, groin and knees are usually a deeper red color compared to the overall rash. After 7-14 days, the rash sloughs off and peeling is usually present.
    • The face may look very flushed, but the skin around the mouth appears normal or pale.
    • The tongue can look like a strawberry-red with bumps.
  • Treatment
    • Streptococcal bacteria is treated with antibiotics.
    • Have your child seen by your doctor immediately if you suspect he or she has strep throat or scarlet fever.
    • Your child will require a full course of antibiotics, which should be completed even if your child is feeling better before he or she completes the course.
    • Your child may return to school  24 hours after starting the antibiotics if the fever has resolved and he or she is feeling better.

Fifth disease, also known as erythema infectiosum or "slapped cheeks" disease, is caused by a virus (parvovirus B19) spread via respiratory secretions such as coughs, sneezes, saliva, or nasal mucus. This disease tends to occur in the winter and spring but can happen year-round.

  • Symptoms
    • The child initially feels ill and tired; then a rash appears. The rash is characterized by bright red cheeks (the symptom inspiring the name slapped cheeks disease). The rash is warm, nontender, and sometimes itchy.
    • In 1-2 days a lacy rash spreads throughout the body. The rash appears to fade when the skin is cool, but with a warm bath or with activity, the rash becomes more pronounced. Once the rash appears, the child is no longer contagious.
  • Treatment
    • Fifth disease is not serious in otherwise healthy children but can pose a serious problem for children with sickle cell anemia, leukemia, or AIDS.
    • The disease can also cause problems in the unborn fetus of pregnant women.
    • Because the child is contagious only before the rash appears, children who develop the rash are free to return to day care or school.

Roseola is also called exanthem subitum and is a common childhood illness caused by the human herpesvirus 6 or 7. The disease usually occurs in children younger than 4 years.

  • Symptoms
    • The symptoms are a high, spiking fever for typically 3-4 days followed by the onset of a rash.
    • The rash is small, pink, flat, or slightly raised lesions that appear on the trunk and spread to the neck and arms, and sometimes then to the face and legs.
    • The rash appears after the fevers begin to abate. This illness is many times referred to as “fever, fever, fever...rash”.
  • Treatment
    • Despite the worrisome fever, the disease is not harmful and gets better without specific therapy. Fever can be managed with acetaminophen or ibuprofen.
    • The fever, especially if it rises rapidly, may result in a “febrile” seizure in susceptible children. Consult your health care provider if you have any concerns about a seizure.

The enteroviruses, including the coxsackieviruses, are a very common cause of fever and rash in children. Two typical diseases caused by coxsackieviruses are hand-foot-and-mouth disease and herpangina. Coxsackievirus infections are more common in the summer and autumn.

  • Symptoms
    • In hand-foot-and-mouth disease, the children develop fever and rash. The rash includes blisters to the mouth and tongue and to the hands and the feet.
    • Herpangina (not caused by a “herpes” virus) causes a fever, sore throat, and painful blisters or ulcers on the back of the mouth that cause difficulty swallowing. Children may also have loss of appetite, abdominal pain, headaches, and joint pain.
  • Treatment
    • No specific treatment is available except acetaminophen (Tylenol) or ibuprofen (Advil, Motrin) for fever. Aspirin and aspirin-like products should ALWAYS be avoided in children as it can cause a life-threatening condition called Reye's syndrome.
    • Make sure the child is well hydrated since pain in the mouth and throat can lead to less liquid intake and dehydration.
    • The diseases are not harmful but can be prevented with good hand washing and not eating off someone else's plate or sharing straws.

Impetigo is a superficial skin infection with streptococcal or staphylococcal bacteria. It is often found around the nose and mouth but can occur anywhere. The rash is more common in the warmer months. It can also include infection of skin that has been damaged.

  • Symptoms
    • Impetigo begins as small superficial blisters that rupture leaving red, open patches of skin.
    • Often a honey-colored crust forms over this rash.
    • The rash is sometimes itchy.
    • Impetigo is also highly contagious. A child can spread the infection to other parts of their own body or to other people.
  • Treatment
    • This infection of the skin is easily treated with topical or oral antibiotics and washing the skin with antibacterial soap.
    • Your child usually is no longer contagious after 2-3 days of therapy, and the rash begins to heal in 3-5 days.
    • If the rash does not show signs of healing by the third day of treatment, or if it continues to spread while on therapy, your child needs to be seen by your doctor.
    • When the impetigo occurs in conjunction with poison ivy or scabies, your child may benefit from an anti-itch medication while the antibiotics are taking effect.

Because children often share many things and are less likely to take cleanliness precautions than adults, parasites and fungal infections can spread quickly through a day care or your child's class at school. Pay attention to any prolonged itching or hair loss your child might experience.

Scabies

Scabies is an itchy rash that is often worsened with bathing or at night. It is caused by a mite, a very small insect (Sarcoptes scabiei) that burrows beneath the top layer of skin. It is spread by close bodily contact such as sleeping together or sharing of clothing. It can also be sexually transmitted. Mites can survive for several days in clothes, bedding, and dust.

  • Symptoms
    • The rash starts about 2 weeks after your child has come into contact with the mite.
    • The itchy rash of scabies tends to be found between the fingers, in the armpits, and on the inner wrists and arms. It tends to spare the head, palms, and soles except in infants and with severe infestations.
    • Sometimes you can see the wavy pattern where the mite has burrowed.
  • Treatment
    • To prevent scabies, good hygiene, frequent hand washing, and not sharing clothing with friends is important.
    • If your child has an itchy rash that lasts for more than 2-3 days, he or she should be checked by a doctor.
    • Prescription medications are available to kill the mites and to decrease the allergic skin reactions of swelling and itch.
    • Once anyone in the family is diagnosed with scabies, everyone in the home should be treated for mite infestation.
    • All clothing and bedding must be washed in hot water and the mattresses vacuumed.

Ringworm

Ringworm is a local infection of the skin with a fungus, usually Microsporum canis, Microsporum audouinii, orTrichophyton tonsurans. Doctors refer to these infections as "tinea" with several forms such as tinea corporis (ringworm on the body) and tinea capitis (ringworm of the scalp). Although the 2 are caused by the same organisms, they are treated differently. Ringworm can be caught from friends (exchanging combs, brushes, or hats) or from household pets. If you think your child may have ringworm, you should see your doctor.

  • Symptoms
    • With tinea corporis, the lesion starts as a red, slightly scaly, oval that gets bigger over time.
    • The rash may be slightly itchy.
    • The center of the rash may clear and appear to be normal skin.
    • Tinea capitis usually starts with a round to oval area on the scalp with hair loss
    • Sometimes, the area of the scalp will swell and may ooze. This is called a kerion and is a reaction of the body to the tinea fungus.
    • Tinea capitis may also present as normal-to-severe dandruff with hairless patches on the scalp.
  • Treatment
    • Tinea corporis can easily be treated with topical medications available from your doctor.
    • Unfortunately, it can be easily spread among family members and friends, making multiple unwanted return visits.
    • Good hygiene combined with appropriate therapy can break this cycle.
    • If complications such as a secondary bacterial skin infection occurs,or there is no improvement after four weeks, call your doctor.
    • Tinea capitis requires an oral medication from your doctor.

Athlete's Foot

Athlete's foot (tinea pedis) is also caused by a fungal infection of the skin.

  • Symptoms
    • A very itchy rash between the toes is usually caused by athlete's foot.
  • Treatment
    • Although athlete's foot can be treated with over-the-counter medications, other causes of rash can appear similar. It is best to have your child checked by the doctor if you suspect athlete's foot.