Chicago health officials announce new policy to slow measles outbreak

The Chicago Department of Public Health said the new policy was necessary because of the continued increase in measles cases among young children at the Halsted Street shelter. The second dose will help protect preschool children until their immunity to measles is fully developed and will also help stop the spread to other children who haven't received a second dose of the shot.

The city has reported 26 measles cases, 19 of which have been in children under 5. Most of the cases have been associated with the Pilsen migrant shelter.

Health care services at Pilsen migrant shelter fall short of promises, medical advocates say

"While the MMR vaccine is the best protection against the virus, children are at highest risk for contracting breakthrough measles after receiving one dose of the vaccine, especially those less than 5 years old," said CDPH commissioner Olusimbo Ige. "We're seeing some of these cases at the Halsted shelter, which isn't surprising. I understand this will be a challenge for families, but we want to do everything to protect young children from contracting measles by ensuring 2 doses of the MMR vaccine."

The policy was also extended to include children between 1 and 5 years old, health officials said.

Families at the shelter with children between 1 and 5 are asked to keep them home until 21 days after receiving the second dose of the vaccine or 21 days after last exposure if they cannot be vaccinated.

Local

The new policy will affect about 50 children at the shelter, health officials said. All eligible children have already received at least one dose of the vaccine.

Initial symptoms — such as high fever, cough, runny nose and red or watery eyes — usually appear within a week or two of exposure to the virus, according to the CDC. A rash can appear three to five days after initial symptoms begin.

The "highly infectious" virus is spread through coughing, sneezing or contact with an infected person, and the virus can live for up to two hours in the air after an infected person has left a space, according to the CDC. Those with the virus can spread it up to four days before and after a rash appears, and 90% of people without immunity who are exposed to the virus become infected.

A Centers for Disease Control and Prevention team has been assisting the city in responding to the infections.