Nearly 5 million children who lack health insurance nationwide are eligible for government-funded coverage but haven't been enrolled, a new report says.

California and Texas each have about 700,000 of those eligible but uninsured kids, accounting for 30 percent of the nation's total — a statistic familiar to Sonoma County health care officials.

"I'm not surprised," said Kathie Powell, chief executive officer of the Petaluma Health Center.

Despite a 12-year campaign to get more Sonoma County children insured, local officials believe the number without coverage may be larger than it was in 1998, in part due to the slumping economy.

"There's still a lot of work to be done," Pedro Toledo, enrollment coordinator for Healthy Kids Sonoma County, said recently.

The report released Friday by the Urban Institute did not include county-level statistics, but said that 65 percent of the nation's 7.3 million uninsured kids — or 4.7 million children under 19 — were eligible in 2008 for either Medi-Cal or the Children's Health Insurance Program, called CHIP.

California has 695,000 eligible but uninsured kids, the report said.

The Petaluma Health Center employs three fulltime workers whose job is enrolling patients in health care plans and still can't close the gap, Powell said.

The center estimates there are 16,000 uninsured adults and children in the south county area, including Rohnert Park, Cotati and Petaluma, Powell said.

Studies show that many people are unaware of their eligibility for health coverage and avoid seeking care, Powell said. "They end up not taking their children to the doctor," she said.

The Petaluma center serves about 15,000 patients a year, most of them covered by Medi-Cal or Medicare. About 23 percent of the clinic's patients are uninsured.

As health care insurance premiums creep upward, local employers either drop insurance or limit it to workers only, so "fewer and fewer children are covered," Powell said.

For many workers who have lost their jobs, there remains a "stigma about being enrolled in a government health program," said Mary Szecsey, executive director of West County Health Centers.

Local health officials cite the loss of 18,000 jobs since 2007 as a major factor in the growing number of uninsured families.

"It's hard to catch up," Szecsey said.

A U.S. Census Bureau report in July said there were 14,730 Sonoma County children and teens under 19 who lack health insurance, representing 13.4 percent of the county's youth population.

Statewide, the report said 12.4 percent of children were uninsured.