Fairfax County's top health official warned yesterday that this year's rabies outbreak will be worse than last year and that the problems caused by the disease will be particularly bad during the spring, when wild animal young are born and people and pets start spending more time outside.

"I'm afraid we're heading for a worse year," said Dr. Richard Miller, director of the county health department. "Barring something drastic or dramatic, I'm afraid we're headed for a record year." Before last year, when 298 rabid animals were reported in Fairfax, the county averaged 30 to 35 rabid animals reported a year.

In a presentation before the county Board of Supervisors, Miller said rabies has been found in 125 animals this year -- 2 skunks, 1 groundhog and the remainder raccons. "That's more than one a day," said Miller.

There have been 187 cases reported in Virginia this year. Maryland has had 250 reported cases. The District has had 15 reported cases since October, when the city's first case since 1968 was reported. Last year, 676 rabid animals were reported in Virginia and 152 in Maryland.

The Northern Virginia counties of Fairfax, Loudoun, Prince William and Fauquier have led the state in reported cases. Isolated cases have been reported in Arlington. In Maryland, the incidence has been highest in Montgomery, with scattered cases in Prince George's, Anne Arundel, Frederick, Washington and Allegany counties.

There have been nine reported human rabies cases in the nation since 1979, and none of the victims has survived. A Marine Corps captain from Quantico Marine Base has been receiving treatment at Walter Reed Medical Center since March 2 with a suspected case of rabies. He is in critical condition. He is believed to have contracted the diease from a raccoon while hunting near the Marine base.

A. Martin Cader, director of the state bureau of communicable diseases, said it would be hard to predict when the outbreak will subside. Cader said that while some of the outbreak may be due to hunting clubs bringing the raccons into the area from southern states, "We don't truthfully know why the epidemic is going on. It could be a result of increased reporting, better lab techniques, it's hard to say."

Cader said some decline in reported cases could surface in statistics soon, now that the Virginia Commission of Game and Inland Fisheries has banned the relocation of raccoons into the Virigina area.

Richard F. Amity, director of the Fairfax department of animal control, which is responsible for trapping the rabid animals, said, "Seventy to 75 percent of the wild animal problems occur between April, May and June."

Raccoons breed in December and January, and their young will be born in the next couple of weeks, Amity said. Cader said offspring of rabid animals may be born with the disease. Spring is also gardening season, and raccoons are attracted to fruits and vegetables.

In addition, the warm weather brings more people and pets outside, exposing more people to the infected animals, which, besides raccoons, skunks and groundhogs, have included foxes, cats, dogs, ferrets and cattle. Experts say the greatest danger of human exposure occurs when pets come in contact with rabid animals and then expose humans.