Health care experts Monday warned that the nation's debt crisis could lead to budget cuts that could cripple the nation's $11 billion plan to expand primary health care.

Meanwhile, the worst Wall Street sell-off in two years served as an uncomfortable backdrop as Sonoma County's former public health officer called for continued support of federally subsidized health centers — the backbone of primary care under President Obama's Affordable Care Act.

"This is a concern...that in these tough economic times, some of that funding might be targeted," Mary Maddux-Gonzalez said following a press conference held in Santa Rosa Monday to announce the concerns.

Maddux-Gonzalez, who is now chief medical officer for the Redwood Community Health Coalition, said that earlier this year Congress reduced funding to health centers by $600 million.

Herb Schultz, regional director of the U.S. Department of Health and Human Services, who also attended the press conference in Santa Rosa, said the cuts made by Congress were from a different pot of money. He said Obama would continue to work to support the country's community health centers.

Health centers are part of "our ultimate goal of making sure every American, no matter where they live, has access to the primary and preventive care they need to stay healthy," Schultz said in an e-mail following the conference.

He said the federal government has provided resources to help health centers reach an additional 2.5 million patients. Under, the Affordable Care Act, a fund for community health centers will provide $11 billion over five years for health center operating, expansion, and construction costs.

But Maddux-Gonzalez said that the $600 million cut alone has reduced the ability of clinics to serve 5 million new patients, a figure based on an equation derived by the National Association of Community Health Centers.

The association, in a report issued Monday, found that for every $1 million in federal funding cuts, health centers lose the capacity to serve 8,297 patients. The group also found that the number of uninsured patients at health centers grew by 36 percent between 2004 and 2009, even as state funding to health centers decreased by 42 percent in the past two years.

In Sonoma County, nearly 25 percent of the population receives health care from one of several community health centers, Maddux-Gonzalez said. Almost half of all Latinos in the county get their health care from such clinics, she said.

The explosion in community health centers has been fueled by federal dollars that began flowing under former President George W. Bush and have continued with a torrent of federal stimulus dollars.

But some worry that the current budget crisis could lead state and federal politicians to make deep cuts in the nation's primary care safety net.