A Centers for Disease Control and Prevention survey released Thursday shows 80.4 percent of Oklahoma children in that age group were fully immunized against 10 deadly and devastating diseases, including polio and hepatitis B.

"This represents a 4.7 percent increase over the previous year when 75.7 percent of these children were fully immunized," said Oklahoma Secretary of Health and Health Commissioner Dr. Michael Crutcher in a press release.

He attributed the increase to Oklahoma doctors' efforts, health department outreach and use of the OK By One immunization schedule.

Don Blose, OSDH immunization service chief, said challenges remain to keeping immunization rates rising, including the rising number of immunizations needed, increasing costs and ensuring all recommended vaccines are available in provider clinics statewide.

About 70 percent of Oklahoma children receive vaccinations from private physicians, he said.

"Even though we have achieved great success controlling these diseases with vaccines, we now face different challenges to protecting the health of children," Blose said.