The Compton Unified School District and St. John’s Well Child and Family Center today will offer free immunization against tetanus, diphtheria and whooping cough.

The so-called Tdap booster will be provided by St. John’s mobile Health Access Express Clinic, which will be stationed at the Compton Unified School District enrollment center at 417 ALondra Boulevard from 8:30 a.m. to 5 p.m. today. The booster is recommended for children 11-12 years old.

The campaign to immunize more than 400 Compton students began Tuesday.

On Thursday and Friday, it will move to the W.M. Keck Foundation Health Center at 2115 N. Wilmington Ave. and to the St. John’s health center at Dominguez High School at 15301 S. San Jose Ave.