Montgomery County's rabid raccoon problem -- which five months ago was fodder for an irreverent exchange between a County Council member and a top county aide -- has turned serious with the discovery of a third rabid raccoon in the county.

Health officials warned of an increased risk of rabies to dogs, cats and humans after a raccoon found in Fox Hills West, a Potomac area subdivision, was confirmed Tuesday as rabid. It was the first of the three found in a residential area.

"Months ago. . . it was a political issue. Now we have a different ballgame," said Dr. Lewis Holder, the county health officer.

The incidence of rabid raccoons also has escalated in Western Maryland and Virginia's worst outbreak in a decade has spread into its northern suburbs. Last month, Arlington County health officials confirmed that county's first case of a rabid raccoon since 1974.

Rabid raccoons are most likely to bite dogs, which tend to chase the cat-sized animals. County officials said they have no recorded case of a wild raccoon biting a human, but they cautioned that humans as well as dogs can contract rabies if bitten or scratched by a rabid raccoon.

"When they are rabid, they have a tendency to strike out and bite," said Dave Wheeler, director of the department of animal control and humane treatment. "But they won't chase you down the street at a hundred miles an hour either. If you see a wild animal, just stay away from it. Go back in the house."

Although there is no way to know if an animal is rabid until tested, officials suggested that raccoons -- normally nocturnal creatures -- seen during the day and appearing listless should be avoided.

Wheeler said the animal control department will give free vaccinations to dogs at the county office building on Oct. 17 and 24, and Nov. 7. Cats can receive free vaccinations on Oct. 13 at the animal shelter on Gude Drive. Also, county police officers will step up enforcement of leash laws for dogs.

Although there is a waiting list, Montgomery County provides free traps upon request, and Wheeler said he has two employes working fulltime to help deliver the two-foot wire-mesh cages and to collect them once the raccoons are trapped inside. The two employes were pulled away from other jobs after the department's part-time trapper position was eliminated in a budget cut.

The elimination of that job prompted a caustic exchange last summer between Council member Esther Gelman and Edmond F. Rovner, special assistant to County Executive Charles W. Gilchrist. Shortly after Gelman criticized Gilchrist for eliminating the trapper position, Gilchrist issued the first warning of a possible rabies outbreak, saying that all dogs and cats should be vaccinated. Gelman called that warning inadequate, saying dogs and cats could not read the warning, and Rovner responded: "I'd be more worried about being bitten by Esther."

Yesterday, Gelman, feeling somewhat vindicated, called the latest plans inadequate. "We should be at a full alert," she said. "There should immediately be a full-scale program for trapping. It was never an appropriate subject for wise-guy remarks or political barbs."

Information about traps and vaccinations can be obtained by calling 279-1823. Other information about rabies is available from the health department, 681-5000.