Migrant Measles Cases Spark Fears of Wider Outbreak

The first measles cases in five years in Chicago are sparking concerns of a wider outbreak, though officials say that vaccination should keep most people healthy.

On Tuesday, the Chicago Department of Public Health (CDPH) confirmed three more measles cases from new migrant arrivals at a shelter in Pilsen in the Lower West Side. The CDPH is coordinating what it calls "a comprehensive, city-wide response" that has included in-person support from the Centers for Disease Control and Prevention (CDC) to curb the effects of the infectious virus.

The measles-mumps-rubella (MMR) vaccine is encouraged to prevent and protect from measles. Most Chicagoans were likely vaccinated as children, although children aged 12 years and younger may be more prone due to not receiving the vaccine based on weak immune systems.

"While we're seeing new cases every day, this is not like the COVID-19 outbreak. The vast majority of Chicagoans are vaccinated against measles and therefore not at high risk," said CDPH Commissioner Olusimbo Ige in a statement.

"But those who are unvaccinated need to take precautions and if they're exposed, quarantine immediately and connect with your healthcare provider. Above all else, get vaccinated so you, too, can be protected from this virus."

The three new cases confirmed on Tuesday brings the total to eight in the last week, one of which officials say was unrelated to new migrant arrivals.

"We have no reason to believe that new arrivals are bringing infections to Chicago," Jacob Martin, CDPH's public information coordinator, told Newsweek.

"In this case, we believe the opposite, as the first measles infection identified in Chicago was not found in the new arrivals population, and 17 different states in the U.S. are currently experiencing an emergent measles outbreak of some kind due to reduced vaccination rates," he said.

Martin went on: "Measles is already here in the United States, but the migrant population on the whole is under-vaccinated compared to the traditional Chicago population and is therefore at higher risk of infection."

Because migrants are less likely to be vaccinated, Martin said, CDPH is coordinating with health care partners to provide MMR vaccinations to shelter residents. The city provides vaccines at various clinics to uninsured individuals at no cost.

The CDC declined to comment to Newsweek, deferring comment to CDPH.

Measles is a contagious respiratory infection that causes a rash and fever, and is capable of leading to pneumonia and other complications. Symptoms include high fever, rash, cough, runny nose and red eyes.

It spreads through the air via coughs or sneezes. A non-immune individual can contract the infection up to two hours after an infected person was in the same room with them. Infected individuals can also spread measles four days before a rash ever appears, and four days after it does appear.

Chicago Mayor Brandon Johnson, a Democrat, has been joined by New York City Mayor Eric Adams and Denver Mayor Mike Johnston, also both Democrats, in calling for more financial assistance from the federal government and President Joe Biden's administration to properly shelter the influx of migrants coming into their cities.

The migrant flows continue to enter the Windy City, some accusing shelter employees of racism and assault. The surges have also dismayed some Chicagoans who have criticized leadership, including Biden, for not addressing the influx at the southern border.

Last month, Illinois Democratic Gov. J.B. Pritzker and Cook County Board President Toni Preckwinkle said continued sheltering of migrants requires an additional estimated $321 million to maintain facilities and services—letting taxpayers foot the bill for some $70 million.

Update 3/14/24, 8:30 a.m. ET: This story was updated with comments from Jacob Martin, public information coordinator for CDPH.