Graphic created by Taylor Schultz.

This story was produced and originally published by Wisconsin Watch in collaboration with Door County Knock.  It was made possible by donors like you.

Before the 1960s, hundreds of thousands of Americans faced measles infections each year. The advent of vaccination eliminated the disease in the United States by 2000. But outbreaks have returned to some U.S. communities as trust in vaccines wanes in many communities.

More than 1,300 measles cases have been confirmed this year across 41 states, the latest being Wisconsin. That’s after the state Department of Health Services on Saturday announced it confirmed nine measles infections in Oconto County — the first in Wisconsin this year. 

Each Oconto County infection involved exposure to a “common source during out-of-state travel,” the state health department said in a statement. 

“DHS, in coordination with the Oconto County Public Health, is working to identify and notify people who may have been exposed to the measles virus,” the statement said. “At this time no public points of exposure have been identified and the risk to the community remains low.”  

What should Wisconsin families know about measles? 

Wisconsin Watch spoke with two University of Wisconsin-Madison experts: Dr. Jim Conway, a professor in the Divisions of Infectious Diseases and Global Pediatrics; and Malia Jones, an assistant professor in the Department of Community and Environmental Health.

We gathered additional information from officials at multiple rural public health departments across Wisconsin and reports from the U.S. Centers for Disease Control and Prevention.

Below are some takeaways. 

When and where am I most susceptible to measles?

That depends on individual health and vaccination status. Very young people (especially infants too young to be vaccinated), older adults and people with compromised immune systems face higher risks for contracting measles and developing severe complications.

Measles tends to spread more easily in crowded urban environments and during travel. However, it can spread anywhere, as evidenced by recent rural outbreaks, including those in Texas, where hundreds of infections have been confirmed and two school children have died. All it really takes is exposure to an infected person. Measles is one of the most highly contagious known diseases. It can remain infectious in the air or on surfaces even after an infected person leaves the area.

To put it in perspective, measles is often reported to have an R nought value — the number used to describe contagiousness — between 12 and 18. That means if one person with measles walked into a room of vulnerable people, odds are they would infect 12 to 18 others in the room. 

What should I do if I start having measles symptoms?

Measles often starts with general cold-like symptoms such as fever, cough, runny nose and watery eyes, making it hard to immediately recognize. The rash typically appears a few days after infection — and after a contagious person may have exposed others. 

If you think you might have measles or have been exposed to it, contact your local health department or healthcare provider immediately — especially if you’re unvaccinated or traveled to an area where cases were reported.  Suspected cases can be reported to local health departments even before confirmation, allowing officials to respond more quickly. Experts recommend staying home while waiting for test results to avoid spreading the virus.

What are the risks of measles?

While some think of measles as a mild childhood illness that everyone used to get, it can be dangerous. The disease can lead to a range of complications, from ear infections and diarrhea to more severe pneumonia or brain-swelling encephalitis. Such brain inflammation can affect multiple parts of the body and even cause permanent damage, especially to the brain and hearing. 

Meanwhile, a  rare but fatal long-term brain disease called subacute sclerosing panencephalitis can develop years after the initial infection. 

Some people infected by measles may experience neurological issues or nerve damage later in life.

One lesser-known risk factor: Measles can disrupt the part of the immune system that remembers previous infections, a phenomenon known as immunity amnesia. That leaves people more vulnerable to future viruses for two to three years after a measles infection.

In higher-income countries measles kills 1 to 3 of every 1,000 people infected, 10% to 20% of infections requiring hospitalization — often due to pneumonia, dehydration or severe diarrhea. Encephalitis occurs in about 1 in 1,000 cases, and pneumonia occurs in about 5% of infections. Children who are malnourished or have limited access to medical care face significantly greater risks. 

U.S. health officials have confirmed three measles-related deaths this year. 

What if I’m unsure whether I’ve had measles or the vaccine?

If you were born before 1957, you’re generally considered immune to measles because the virus was so widespread during the pre-vaccine era. Many adults born in the 1960s and 1970s may assume they’re protected when, in fact, they were never fully vaccinated, or even vaccinated at all. A second dose of the measles, mumps and rubella (MMR) vaccine wasn’t added to routine childhood immunization schedules until 1989, so many adults missed one or both recommended doses. 

The bottom-line is if there’s any uncertainty around your vaccination status, it’s safe to get vaccinated again. There’s no harm in receiving an additional dose of the MMR vaccine. In fact, an extra dose is both safe and more practical — quicker and more cost-effective than getting a blood test to check your immunity.

“More is better,” Conway said. “This is not one of the vaccines that has particularly tough side effects.”

Staying up to date not only protects you from serious illness but also helps safeguard others in your community who may be more vulnerable to complications from measles.

What can I do to protect myself and others?

Vaccination is your best defense. The MMR vaccine is the most effective way to protect yourself and those around you from measles. Make sure you’ve received both recommended doses, and stay informed about outbreaks in your community, especially if you’re traveling or belong to a vulnerable group.

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