Measles typically lasts longer than chickenpox and can cause other symptoms, including a high fever, runny nose, and inflamed eyes. Chickenpox can also cause a fever, along with headache and fatigue, among other symptoms.

Chickenpox and measles are viral infections. Both are highly contagious and were once considered common childhood conditions in children under 12.

Both chickenpox and measles cause red rashes on the body. They can both cause fever, too. This is why some people confuse the two conditions, especially in the early days of the infection.

Recognizing other symptoms of these two conditions can help you determine which one you or your child likely have. This article reviews common symptoms and treatments that can help both conditions. It also looks at how you can prevent either infection.

Chickenpox, also known as varicella, is caused by the varicella-zoster virus (VZV). Measles, also known as rubeola, is caused by the measles virus.

Both chickenpox and measles are highly contagious. The Centers for Disease Control and Prevention (CDC) says that 90 percent of close contacts who have not had chickenpox or its vaccine will develop the condition.

The same is true for measles: 9 in 10 unvaccinated people will develop the condition if near someone who has it.

Both viruses are airborne. This means you can pick up the virus if you inhale respiratory droplets from someone who has the condition. You may also acquire both viruses if you touch a surface or object that someone with the condition has come into contact with. Fluid from ruptured blisters can also spread chickenpox.

Both viruses are also contagious before visible signs of the condition appear.

People with chickenpox can pass the virus to others up to 2 days before a rash appears, according to the CDC. They remain able to transmit the virus until all the blisters have ruptured and scabbed over.

The typical chickenpox infection lasts 4 to 7 days. People in high risk groups, like those with weakened immune systems, may have the condition for longer. These people may also have complications as a result of the infection.

People with measles can pass the virus to others up to 4 days before a rash appears. They are then able to transmit the virus for another 4 days after the rash appears.

Measles may take longer to clear, sometimes 2 to 3 weeks. Complications of measles include:

Incubation period10–12 days10–21 days
Contagious period4 days before rash to 4 days after rash2 days before rash until all blisters scab over

Both measles and chickenpox cause rashes, but these rashes differ enough that understanding the two conditions should make telling them apart easier.

The typical chickenpox rash starts as red spots on the chest, stomach, face, and back. It may also spread to other parts of the body.

In 2 to 4 days, a chickenpox rash will develop into fluid-filled blisters, called vesicles. These raised bumps are itchy, and they will rupture and leak fluid. It’s not uncommon for someone to have 250 to 500 blisters.

The ruptured blisters will scab over. Once all the bumps have developed a scab, you are no longer able to pass the virus on to someone else.

Other symptoms of chickenpox include fever, fatigue, loss of appetite, and headache. The blisters can also develop in the mouth.

On the other hand, a measles rash starts as a red and blotchy flat rash at the forehead’s hairline. It can spread, and the spots may begin to run together. In some people, small fluid-filled spots may develop.

Other symptoms of measles include runny nose, cough, sore throat, and red, inflamed eyes (conjunctivitis). People with measles may also develop Koplik spots, which are small, red spots with blue-white centers inside the mouth and on the cheeks.

fevercan be as high as 104°F (40°C)typically 101–102°F (38–39°C)
rashred, blotchy rash along the hairline of the forehead that can spreadred spots, at first typically on the chest, face, and back, that can spread
runny noseyesno
sore throatyesno
conjunctivitis (red, inflamed eyes)yesno
lesions in mouthKoplik spots (small, red spots with blue-white centers)blisters that can form in the mouth
loss of appetitenoyes
duration10–12 days or possibly several weeks4–7 days

In people with dark skin tones, both rashes may not appear visibly red. Instead, they may look darker than the skin around the rashes. Chickenpox on people with darker skin may resemble raised bumps or pimples.

Chickenpox symptoms in adults are usually similar to symptoms in children. However, adults are at a higher risk of severe symptoms and complications.

Since chickenpox and measles are viral infections, antibiotics aren’t an effective treatment. Instead, treatment for these two conditions focuses on easing symptoms and reducing the risk of complications.

People with chickenpox may take an over-the-counter (OTC) antihistamine, such as Benadryl. This medication can help reduce itching.

A doctor may prescribe an antiviral to people at high risk of complications of chickenpox. This medication, acyclovir, may reduce the severity of the infection. You should take it within a few days of contact with someone who has the condition, or it is unlikely to be effective.

People at risk of complications of chickenpox include:

  • those with weakened immune systems
  • pregnant people
  • newborns
  • people with chronic immune-weakening conditions like leukemia
  • adults who have not had or been vaccinated for chickenpox

For most everyone with chickenpox or measles, the focus of treatment is actually on managing symptoms. This may be done at home and usually without medical treatment.

Help reduce and manage symptoms by:

  • getting plenty of rest
  • drinking fluids to stay hydrated
  • staying home from school, day care, or work to prevent the spread of the virus
  • taking antihistamines to reduce itching

Other home management techniques can address symptoms of chickenpox and measles:

  • Use OTC fever reducers, such as acetaminophen and ibuprofen. Do not give children aspirin, since it can cause Reye’s syndrome.
  • Run a humidifier to ease sore throat and cough.
  • Wear gloves, especially during sleep, to deter scratching. Keep fingernails clipped and clean to reduce the risk of infecting blisters.
  • Take cool baths or use cool compresses to reduce itching. Add OTC oatmeal products, which are available at drugstores and pharmacies, to soothe skin.
  • Avoid spicy or acidic foods if blisters develop in the mouth.

Chickenpox and measles are both easily prevented with vaccination. Vaccines for both viruses are part of regular childhood vaccination schedules.

Each vaccine has two doses. Healthcare professionals typically administer the first dose between the ages of 12 and 15 months. The second dose, a booster, is typically given between 4 and 6 years old.

Today, 90 percent of children receive their first dose for both viruses by age 2. The chickenpox vaccine alone prevents about 3.5 million cases each year. It also means 9,000 fewer hospitalizations and 50 fewer deaths every year.

Many people today may not have had the chickenpox vaccine as children. It became available in 1995. Before that, it was a very common childhood condition.

However, their children can get vaccinated, and they can rest assured it’s highly effective. According to the CDC, getting two doses of the chickenpox vaccine is more than 90 percent effective at preventing chickenpox.

If you’re an adult who didn’t have chickenpox as a child and aren’t vaccinated, you can still get the vaccine. It will protect you from chickenpox and help avoid potentially spreading it to other people in your community.

Avoiding a chickenpox infection may help you avoid another condition later in life: shingles. The varicella-zoster virus, which causes chickenpox, remains in the body after the infection is over. It goes dormant in the nervous system and can later reactivate as shingles, a painful skin rash.

Children who are vaccinated against chickenpox are much less likely to develop shingles when older. A shingles vaccine is also available for people who had chickenpox.

Likewise, the measles vaccine is very effective. After one dose, it is 93 percent effective at preventing infection, and after two doses, it’s 97 percent effective.

Measles was declared eliminated in the United States in 2000. However, the CDC reports that measles cases have been climbing in recent years as unvaccinated individuals travel abroad and bring the infection home.

As with any vaccination, both the measles and chickenpox vaccines carry some risk for mild side effects. They include:

  • soreness and redness around the injection site (more common in adults than children)
  • temporary pain and stiffness in joints
  • a mild rash
  • a fever

More severe complications of vaccination are rare.

An allergic reaction, or anaphylaxis, can occur, and it can be life threatening. Symptoms include difficulty breathing, hives, a faster heartbeat, and weakness.

If you or your child show signs of an allergic reaction following a vaccination, call emergency services.

Chickenpox and measles were once common childhood infections. They both begin as red rashes, but the appearance and location of the rashes can tell you a lot about which infection you are likely experiencing.

Today, vaccinations have greatly reduced the cases of both chickenpox and measles in the United States. In fact, measles is so rare that it was considered eliminated at one point. However, unvaccinated individuals continue to reintroduce the virus back into the population and spread it.

If you have had chickenpox in the past, you are unlikely to develop it again. Breakthrough infections in people vaccinated against chickenpox can occur, but symptoms tend to be milder, with few or no blisters.

Measles, on average, is a longer condition, and complications may be more common. However, once you have measles, you cannot get it again.

Vaccines for both chickenpox and measles are highly effective and safe. They can help prevent you or your child from experiencing illness and reduce the spread of these infections in your community.