In 2011, the first of the 78 million baby boomers will turn 65. But only one out of every 100 doctors is a certified geriatrician specializing in treating the elderly. And that is a growing concern for those in medicine.

"The actual number of certified geriatricians is currently going down each year, not up," said Dr. Jack Rowe, who helped craft the Insitute of Medicine's April report on the potential shortage of health-care workers to deal with the aging population.

Only half of geriatric training positions are filled each year. And 60 percent of those positions are filled by doctors from other countries who have come to the U.S. to study medicine — and they may go back to their home countries to practice.

"It's not a sexy field to go into. It's not well-reimbursed," said Dr. Colleen Christmas, an assistant medical professional at Johns Hopkins Medical Center.

In fact, doctors say, Medicare pays so much less than most private insurance that a geriatrician makes about $15,000 less than a general practitioner. With fewer doctors going into geriatrics, medical schools such as Johns Hopkins are taking a different tack.

"In the last four to five years, we've ramped that up dramatically. Now that boomers are just around the corner, we've integrated geriatrics into many different parts of residency training," Christmas said.

The problem extends to nursing, too. Experts predict a need for 800,000 more nurses — and 200,000 more nurses' aides — to help care for boomers as they get older.