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What is measles? -

Measles is a highly infectious, dangerous disease caused by a virus. This virus causes a number of symptoms, notably a skin rash.

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Vaccine development -

While it was quite a common childhood disease in the past, measles can now almost always be prevented with a vaccine.

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Vaccine development -

While the worldwide death rate attributed to measles has fallen since the vaccine was developed, it still kills more than 200,000 people each year—mostly children.

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Spread -

It moves through the air, when people speak, cough, or sneeze. A person carrying the virus can infect up to nine out of every 10 unprotected people in the same room, making it highly transmissible.

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Symptoms -

It typically starts with cold-like symptoms, including a high temperature, a runny or blocked nose, sneezing, a cough, and sore, red eyes.

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Symptoms -

Small white spots inside the mouth typically appear next, while the skin rash develops afterwards. The rash begins on the face behind the ears, spreading to the rest of the body.

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Contagious -

Measles is contagious for around eight days in total—for four days before the rash appears, and for four days afterwards.

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Age danger -

Children under the age of five and adults over the age of 20 are more likely to suffer complications from a measles infection.

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At-risk groups -

Pregnant women and those with compromised immune systems, such as from leukemia or HIV infection, are at a higher risk of suffering complications from measles.

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Side effects -

Ear infections and diarrhea are common complications, while more severe complications include pneumonia and encephalitis (inflammation of the brain).

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Neurologic infection -

Neurologic infection with measles is relatively rare, occurring in only one out of 1,000 cases. However, neurologic infection carries a much higher risk of permanent harm, including death.

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Immunosuppression -

A loss of immune memory occurs after measles infection, resulting in immunosuppression, which increases the risk of dying for up to three years after contracting measles.

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Fatal complications -

Rare but potentially fatal complications can occur after infection, including a demyelinating disease (causing damage to myelin in nerve tissue) called acute disseminated encephalomyelitis (ADEM). This can occur two weeks after infection.

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Fatal complications -

ADEM is a brief but intense attack of inflammation in the brain, spinal cord, and occasionally the optic nerves, which damages the brain's myelin.

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Fatal complications -

Another rare but deadly complication of measles infection is subacute sclerosing panencephalitis (SSPE), which typically occurs seven to 10 years later.

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SSPE -

SSPE, also known as Dawson's disease, is a progressive neurological disorder of children and young adults. It's a slow and persistent viral infection that affects the central nervous system.

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Risks during pregnancy -

If you catch measles while pregnant, it can harm your baby. Measles in pregnancy can lead to miscarriage, stillbirth, premature birth (before the 37th week of pregnancy), or the baby having a low birth weight.

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A serious disease -

Some people might think measles is a simple rash and fever that subsides after a few days, but as you can see, it can cause serious health complications.

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Severity -

There's no way to tell in advance how severe the complications will be in a person who contracts measles. But one in every five people who contract it in the US will be hospitalized.

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Mortality rate -

One to three out of every 1,000 people will die, even if they receive the best possible care. One out of 1,000 people who catch measles develop brain swelling, which could lead to damage.

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Vaccinated people and immunity -

More than 99% of people who receive both doses of the MMR vaccine develop immunity to measles. As immunity from the vaccine is so effective, the disease is not as common as it once was.

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In the past -

In the '60s, measles was extremely common, with epidemic outbreaks taking place every two to three years. It's estimated that up to 2.6 million deaths from measles occurred each year worldwide.

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Deaths -

In the 1960s in the US, there were between three and four million cases of measles every year, resulting in 400 to 500 deaths.

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Measles today -

It's extremely uncommon for those who've received two doses of the vaccine to contract measles, but it's not impossible.

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Global spread -

In the US, measles is generally imported from abroad and spread in unimmunized and under-immunized people.

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Testing -

A physical exam is the primary way measles is diagnosed, but blood samples, urine samples, or nose and throat secretions can also be tested.

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Treatment -

There is no cure for measles. The virus must run its course, which takes between 10-14 days. Symptoms are managed with NSAIDs, rest, drinking lots of fluids, gargling salt water, and avoiding harsh lights.

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Contacting your healthcare provider -

If you think you or your child might have been in contact with someone who has measles, or if you or your child have measles and it doesn't appear to be getting any better, contact your healthcare provider.

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Contacting your healthcare provider -

Measles isn't the only disease that causes a rash and fever. Roseola, rubella, chickenpox, and scarlet fever have similar symptoms. If in doubt, get in touch with your healthcare provider.

Sources: (Cleveland Clinic) (Piedmont Healthcare) (CDC) (WHO) (UChicago Medicine)

See also: What it was like to live through the 1918 "Spanish" flu pandemic

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