Measles outbreak in Chicago: What to know about the virus

Chicago health officials recorded the city’s first measles case in five years earlier this month with an unknown origin.

Soon after, an outbreak spread to the city’s largest migrant shelter. On Tuesday, Chicago’s total sat at 31 cases, with two reported in suburban Will County and Lake County.

Though most vaccinated people have close to zero chance of contracting the virus, here’s what to know about the disease.

Does anyone still get measles?

Yes, they do.

In fact, measles, which was considered eliminated in the United States in 2000, has reemerged in recent years.

In the first quarter of 2024, reported cases of measles are climbing. As of March 21, 2024, 17 jurisdictions reported 64 measles cases: Arizona, California, Florida, Georgia, Illinois, Indiana, Louisiana, Maryland, Michigan, Minnesota, Missouri, New Jersey, New York City, Ohio, Pennsylvania, Virginia and Washington. That’s more than the total number of cases reported – 58 – in all of 2023, according to the Centers for Disease Control and Prevention.

How is measles transmitted?

The measles virus is transmitted by direct contact with infectious droplets or by airborne spread when an infected person breathes, coughs, or sneezes, according to the CDC.

How can I protect myself from measles?

The spread of measles starts and ends with vaccination, said University of Chicago Medicine pediatric infectious disease specialist Dr. David Zhang.

The current form of measles vaccine is the measles, mumps or rubella (MMR) vaccine, introduced in the 1970s. The MMR, available at most physician and primary care offices, should be taken in two doses, at least 28 days apart, according to the CDC.

The MMR is typically administered to children between 12 and 15 months and then age 4 to 6 by their pediatrician as part of their vaccination schedule.

Adults who have not been vaccinated should get at least one dose of the MMR vaccine. Certain adults with preexisting conditions might be advised by their physician to get two doses.

Two doses of the MMR vaccine are about 97 percent effective, according to the CDC.

What if I’m not vaccinated from measles?

For unvaccinated populations, measles is one of the most contagious pathogens and can cause serious illness in young children, pregnant women and people with weakened immune systems, according to health officials.

What are the symptoms of measles?

Symptoms of measles typically occur 10 to 14 days after exposure and can include a fever, cough, runny nose, watery eyes, high fever and a rash.

How effective is the vaccine for measles?

Vaccines for measles were first introduced in the United States in the 1960s and are among the most effective vaccines available, according to the CDC.  Knowledge of measles hasn’t changed since the introduction of the vaccine, according to infectious disease specialists.

Can you contract measles multiple times?

Once someone contracts measles, they are presumed to have full immunity. Still, health officials encourage vaccination for people with measles.

It is not harmful to receive the MMR vaccine after exposure to measles, according to the CDC.

Receiving a vaccine within 72 hours of exposure could lead to less severe complications and provide some protection against the disease.

Those who suspect they have measles should confirm with a lab test since symptoms can look similar to a slew of other infectious diseases, Dr. Zhang said.

Should you quarantine if exposed to measles?

Generally, the only people needing to be quarantined are unvaccinated populations who cannot get the vaccine quickly after exposure, according to Dr. Zhang. The quarantine period is 21 days after exposure, the time frame for developing symptoms.

What is the treatment for measles?

There is no specific cure for measles since it is a virus that must run its course, according to the CDC. If caught within three days of exposure, the MMR vaccine is a treatment that can lessen symptoms and provide future protection.

Bedrest, frequent fluids and fever reducers can help with symptoms. According to the Illinois Department of Public Health, antibiotics do not help, and there are no antiviral drugs to prevent or treat measles.

I’m not sure I am vaccinated. What should I do?

If you’re not sure if you are vaccinated, the CDC advises you to contact your state’s health department. Some states have registries (Immunization Information Systems) that include adult vaccines. You can also contact the health department of the state in which you were born or spent your childhood. In Illinois, you can submit an immunization records request.