TORONTO - A Brampton father is livid after learning his three-year-old daughter was one of nearly a dozen kids who accidentally received double the recommended dose of the H1N1 vaccine at a Peel Region Public Health clinic.

Ted Hedrich says his wife, Lisa, brought their little girl, Selena, to a clinic on Indell Lane in Brampton around 4:30 p.m. Monday.

Three days later, the couple received a disturbing call from public health officials alerting them there had been a mistake with the shot given to their daughter, who by then had fallen ill with flu-like symptoms.

"They told me the nurse had given our daughter an adult dose of the swine flu vaccine," Hedrich said yesterday. "I freaked out! I absolutely freaked out!"

Health officials have urged all children under 5 to get the H1N1 vaccine. But they also recommend young kids only get half the adult dose initially and then get the other half several weeks later.

Hedrich, 51, said his daughter woke up sick Tuesday, the morning after receiving her shot.

At first, he and his wife just assumed their only child was having a "bad reaction" to the vaccine and they weren't too concerned.

But after the call from public health Thursday they can't help but worry about other side effects surfacing in the future.

"It's scary!" said Hedrich, a project engineering manager. "They've failed us miserably and there seems to be no accountability."

Peel Public Health admits a nurse working Monday administered 0.5 ml of the H1N1 vaccine instead of 0.25 ml to 11 children. But they say the mistake was caught within about an hour and an investigation is under way.