Measles — a deadly scourge of children before a vaccine was invented in 1963 — is back.
Health officials in Wisconsin and Illinois are warning the public that one case has been reported in each state.
The Illinois case was discovered in Cook County, the state’s most populated county, which includes Chicago. In neighboring Wisconsin, measles was reported in a Milwaukee resident who works in suburban Waukesha County.
As a result, public health experts are now struggling to track down people who may have been exposed to the infectious disease.
The Illinois case occurred in a resident who was unvaccinated and had been exposed to measles during international travel, according to the Illinois Department of Public Health (IDPH).
“This first reported case of measles in Illinois since 2019 is a reminder that this disease can be prevented with up-to-date vaccination,” IDPH director Dr. Sameer Vohra said in a news release.
“However, as we saw this week, it still can affect those who are unvaccinated. I urge everyone to make sure they and their family members are up to date on measles/mumps/rubella (MMR) vaccine and all other age-appropriate immunizations,” he added.
What is measles?
Measles is a highly infectious disease caused by a virus. People of any age can get measles, but the disease is most common — and most deadly — in children.
Before a vaccine became available in 1963, nearly all children caught measles by the time they were 15, according to the Centers for Disease Control and Prevention, and an estimated 3 million to 4 million people in the US were infected each year.
And each year, an estimated 400 to 500 people died of measles, 48,000 were hospitalized and 1,000 cases of encephalitis (swelling of the brain) were caused by the disease.
Measles was officially declared eliminated from the US in 2000, thanks to a highly effective vaccination program, as well as better measles control throughout the Western Hemisphere.
A typical measles rash is one of the first symptoms. It’s most often a red, blotchy rash on the face and around the ears, which then spreads downward to the torso and feet, according to the Mayo Clinic.
Other measles symptoms include a fever, dry cough, runny nose, sore throat, inflamed eyes (conjunctivitis) and small, white spots with blue centers on a red background inside the cheek (called Koplik’s spots).
As the rash spreads, an infected person’s fever can rise sharply, sometimes up to 105 degrees or higher. A person can spread the measles virus to others for about eight days, starting four days before the rash appears and ending when the rash has been present for four days.
The measles virus is most easily spread through airborne droplets when an infected person speaks, sneezes or coughs. It can also spread when infected droplets land on a surface and someone touches that surface.
About 1 to 3 of every 1,000 children who become infected with measles dies from respiratory and neurologic complications, according to the CDC.
In most cases, the measles vaccine is given to children as a combined measles-mumps-rubella (MMR) vaccine, or with the chickenpox (varicella) vaccine, known as the measles-mumps-rubella-varicella (MMRV) vaccine.
Doctors recommend that all children receive the MMR vaccine twice: once between 12 and 15 months of age, and a second time between 4 and 6 years of age (before starting school).
Adults may need the measles vaccine if they don’t have proof of immunity and are attending college, traveling outside the US or working in a hospital environment.
Adults born in 1957 or later may need a vaccine if they hadn’t had one and have never had measles. A person who’s had measles has built up an immune system to fight the infection, and you can’t get measles twice.
Most people born or living in the US before 1957 are immune to measles because they’ve already had it.
A now-discredited 1998 report attempted to link the measles vaccine to autism. That caused a drop in the number of children who were vaccinated, which was followed by a steep rise in cases of measles.
A 2023 report in the medical journal the Lancet found that pockets of vaccine hesitancy for measles and other infectious diseases continue to exist, despite the measles vaccine’s success at preventing more than 70 million deaths between 1990 and 2019.
There’s no cure for measles after an infected person develops symptoms, so treatment usually focuses on easing the symptoms.
Doctors advise medication to reduce a fever, including non-steroidal anti-inflammatory drugs such as ibuprofen, acetaminophen or naproxen.
And giving a child a dose of vitamin A may lessen the severity of a measles infection. Other remedies include rest, drinking fluids and avoiding screens and bright lights if they bother your eyes.
And because the disease is easily spread, people with measles are advised to isolate at home and avoid contact with others.
Despite public health measures and vaccination programs, measles outbreaks still occur.
In February, a small outbreak of measles was linked to an unvaccinated person who attended a religious revival at Asbury University in Wilmore, Kentucky. At least three cases were attributed to the revival, and unvaccinated attendees were warned to quarantine if they showed any symptoms.
Measles cases increased by about 80% worldwide during 2022 compared with 2021, according to Precision Vaccination, and India remains the leader globally, with 46,231 measles cases reported over the past year.
The CDC has stated that as of Sept. 29, 29 measles cases have been reported in 16 regions of the US this year — a figure that does not include the cases in Illinois and Wisconsin.