MILWAUKEE — The Centers for Disease Control and Prevention (CDC) over the weekend signed off on the Pfizer and Moderna COVID-19 vaccines for children as young as six months old. 

Dr. Jim Conway, of UW Health, led a clinical trial of the Moderna vaccine in young children. 

He said he's confident the vaccines are safe and effective in kids. 

"The reason why the trials took so long was finding the right dose where you could get rid of most of the side effects while still getting a decent immune response," Conway said.

"These vaccines are very safe in these younger kids," he added. 

But Conway did acknowledge the vaccines do fade in effectiveness over time, and the vaccine strains often don't hold up against new variants of the virus. 

Conway also said, following the CDC's decision, he anticipates families in Wisconsin who want to vaccinate their young children can begin doing so later this week. 

"The federal government started shipping the vaccines out over the weekend to the states," he said.