For all the changes put in motion by yesterday’s historic vote passing health care overhaul, an expansion of coverage for tens of million of uninsured people raises a really big question: Who will take care of them all?

It’s already tough to find a primary care doctor in many parts of the country.

Look no further than Massachusetts, where insurance coverage is as close to universal as any place in the U.S., for a hint of the potential for trouble. Less than half of internists in the state (44 percent) are accepting new patients, according to data collected by the Massachusetts Medical Society last year. And the average wait time for new patients to get an appointment? Forty-four days.

An annual event that foretells the future specialties of new doctors shows there’s no quick fix coming. Last Thursday was “match day,” when seniors at American medical schools got matched with residency slots around the country. Lucrative specialties, such as radiology and dermatology, have been in high demand for years. Primary care, not so much.

The National Resident Matching Program touted the rise this year in students matched to family care programs. But others noted that the increase — 9 percentage points – still leaves a lot of growing room, especially considering the number of patients expected to seek new care because of reform.

Of 2,608 primary care training slots available — 73 more than last year — fewer than half were filled by American med school seniors. “This won’t make up for the shortfall, and there is definitely a shortfall in family medicine,” said Dr. Lori Heim, president of the American Academy of Family Physicians.

Even so, she remains optimistic, “We have a start, now we need to build on it.” Heim says the uptick might be due to all the talk about health care reform recently, from the media to lawmakers, and even President Obama. “The debate has really highlighted family medicine and primary care, and demonstrated that people value that relationship between doctors and the community, and what primary care brings to the health care system,” she told us.

And, she says, parts of the legislation don’t hurt either. The increase in student loans and loan forgiveness could help sway students who have been put off in recent years from primary care because of the much lower salaries those doctors receive compared with specialists and surgeons.

How much ground do primary care recruits need to make up? A lot. While U.S. seniors filled only 45 percent of the available primary care spots this year, specialties that pay much better had a 90 percent fill-rate by Americans.

The bill that the House passed Sunday includes a 10 percent payment bonus for primary care doctors, but Heim says that’s “nowhere near what we need to do to decrease a payment disparity of two- to three-times less” for primary care docs.

Still leaders in the field say they hope the increased numbers this year are the beginning of a turnaround. “This is a small number and in and of itself will not make much of a difference,” said Ed Salsberg, of the Association of American Medical Colleges. “We don’t know yet, but hopefully this is the beginning of a long-term trend upwards.”

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