The Illinois Department of Public Health is encouraging residents who have received their first vaccine dose to sign up for the V-safe After Vaccination Health Checker.

The program will send people a text message when it's time for them get a second vaccine dose. The program is from the Centers for Disease Control and Prevention.

Both the Moderna and Pfizer vaccines require two doses to be effective. The Johnson & Johnson vaccine only requires one dose.

The program can also be used to communicate with the CDC about vaccine side effects.

Anyone interested must sign up within 42 hours of receiving their first vaccine dose.

Signup is online here.