All eligible people at Chicago migrant shelter have been vaccinated for measles in ‘unprecedented operation’

The Chicago Department of Public Health said Wednesday that everyone who is eligible for vaccination at a temporary shelter housing migrants that’s at the center of a measles outbreak has now been vaccinated.

The city learned last week that it had its first measles case since 2019. Illinois is one of 17 states that have seen measles cases this year, according to the US Centers for Disease Control and Prevention. The first case in this outbreak was unrelated to the shelter.

Two more cases of measles in children have been identified by the Chicago Department of Public Health, bringing the total number of cases in the city to 10, according to an update Wednesday.

One of the children resides at a migrant shelter in Chicago’s Pilsen neighborhood, where a measles outbreak has been declared, and attends Cooper Dual Language Academy, a Chicago Public Schools spokesperson said Thursday. The second child lives in a different part of Chicago, health officials said.

Earlier this week, the school district said in a statement that a school-age child living at the shelter had measles. That student attended Philip D. Armour Elementary School in the Bridgeport neighborhood, according to the school district.

Eight migrants at the crowded shelter – five children and three adults – have tested positive for measles. The virus is highly contagious and can cause serious symptoms that can lead to pneumonia and other potentially life-threatening complications, but it is preventable with vaccination. It can spread through the air and through contaminated surfaces and can be difficult to manage in crowded areas.

The temporary shelter was not set up to house as many people as are living in the converted warehouse, according to Alderman Byron Sigcho-Lopez, who represents the area. The shelter was supposed to hold about 1,000 people; there are 1,900 there now.

“Right now, we have people that are in close proximity to one another,” Sigcho-Lopez said.

Because this outbreak was considered an emergency, Chicago Department of Public Health Commissioner Dr. Olusimbo “Simbo” Ige said Wednesday, the city pulled in all of its medical directors and staff, along with other departments and public health officials, to vaccinate as many people at the shelter as quickly as possible.

Staff put in 12- and 16-hour shifts over the weekend in what Dr. Alexander Sloboda, an assistant professor at Rush University’s Department of Emergency Medicine, called an “unprecedented operation” to get a mass vaccination, screening and education effort underway “that’s not really been performed anywhere else in this similar circumstance.”

Of the 1,900 people housed at the shelter, about 999 are vaccinated and immune, Ige said Wednesday. The remaining half who are eligible have been recently vaccinated.

“One of the success stories here, especially for the measles response, is that of all those who are eligible that were offered vaccines, we had no refusals,” Ige said. “Once we provide people with information and opportunity to ask questions and respond to those questions, most people are willing to accept the vaccines.”

Those who have recently been vaccinated are expected to quarantine for the next 21 days, since it takes about that amount of time for the full protection of the vaccine to kick in.

The city said people at the shelter who are immune to measles have been given a card that allows them to come and go. Those who are not immune have been given cards to say they need to quarantine at the shelter.

Residents of the shelter will be monitored daily for symptoms and will be connected to care if they get sick.

Measles is so contagious that if one person gets it, 9 out of 10 unvaccinated people around them will catch the virus. An infected person can spread measles even before they have symptoms, from up to four days before developing a rash and through four days afterward.

Two doses of the measles, mumps and rubella or MMR vaccine are 97% effective at preventing measles if you are exposed to the virus. One dose is 93% effective.

The vaccine provides lifelong protection, according to the CDC. Most people in the US get the two-dose series in childhood.

Measles had been considered eliminated from the US in 2000, but cases have been popping up across the country as vaccinations have declined and more people are traveling to parts of the world where measles is more common.

Dr. Michelle Funk, medical director of the Chicago Department of Public Health, said that it has also been working with the state to move people who are at highest risk of severe illness but are not eligible for vaccination.

“In other words, those with very young children, families with pregnant individuals, [were moved] to a special place that they can stay and be separated from the rest of the people at this facility,” Funk said.

Nine families have been moved to an off-site location, according to Lucia Calderon, Sigcho-Lopez’s chief of staff. The families have children under 1 or expectant mothers, neither of which can be vaccinated.

Illinois Gov. J.B. Pritzker said Wednesday that he called the White House to ask for the CDC’s help.

“I was the one who called the White House to make sure that the CDC would be coming to Chicago to advise and make sure that the actions that are being taken now are put in place,” he said.

The CDC sent a team of experts to the city Tuesday to help with the overall effort and to provide technical guidance when needed.

“This is an unprecedented situation,” Ige said. “There are no other contexts where we have so many thousands of new arrivals and we need to protect them from measles because measles is circulating in the United States. They came here without measles and now they have been exposed to measles and we have to do everything we can to protect them.”

Ige said Chicago has been working hard to take its responsibility to “safeguard the health of the new arrivals seriously.”

“It is important to again emphasize that measles did not come with new arrivals,” he said. “Measles was already here, and those who got infected got infected because measles was circulating in Chicago.”

Dr. Manisha Patel, the chief medical officer at the CDC, said there have been pandemic-related declines in vaccination and global measles activity has increased, raising the risk that people who are unvaccinated can get sick.

“Activity is increased in areas of the country that Americans frequently visit, and that is one of our big concerns about upcoming spring break travel,” she said.

Patel added that a key priority for the CDC is getting more children up to date on their vaccines. With a decline in the number of MMR vaccinations, she said, there are 750,000 kindergartners at risk of measles in the US.

Overall, the US has good population immunity across the board, Patel said, “but if you’re not vaccinated or you don’t have immunity, measles will find you.”

Ige said the hope is that everyone, not just migrants in shelters, will get vaccinated, since it is the best way to protect individuals and those who are not eligible to get the vaccine.

“If you have children under the age of 1, they cannot be vaccinated. So the best way to protect them is to be vaccinated yourself and to ensure that all those who are around them are vaccinated,” he said. “Vaccination, vaccination, vaccination for everybody in the city whether you’re a new arrival or not. Vaccine-preventable diseases can be prevented by getting vaccinated.”

CNN’s Kara Devlin has contributed to this report.

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