Two Virginians - one in Richmond County and the other in Culpeper - have died this year of Rocky Mountain spotted fever, a disease carried by wood ticks and now most common in the Middle Atlantic states, according to the state's bureau of epidemiology.

And a prediction made early in the spring that the tick population would be unusually heavy this year seems to be borne out.

Twenty-three cases of the fever have been reported in Virginia so far, compared with 17 this time last year. North Carolina, with 29 cases, is the only state with a higher total than Virginia. Oklahoma also has reported 23 cases. Maryland has had nine reported cases so far, compared with 27 in all of 1976. Nationwide, there have been 140 cases this year, compared with 99 at the same time last year. There were 892 cases nationwide in 1976.

The Virginia total for 1976 was 100 cases and three deaths.

The prediction of a heavy tick population was made on the basis of warm, wet early spring weather by Dr. Kenneth L. Crawford, chief of veterinary medicine for the state of Maryland.

He said yesterday the validity of the prediction has been demonstrated both by complaints received and his own examination of animals.

Rocky Mountain spotted fever is an infectious disease resulting from the bite of an infected tick or contact with the crushed tissue or faces of a tick for more than four hours.

The disease can cause brain inflammation, blood clotting, Kidney problems and other complications that can lead to death.

Symptoms of the disease include a sudden onset of fever, severe headache, chills and generalized aching from three to 10 days after exposure. A rash appears in three to five days on the arms and legs, including the palms of hands and soles of feet, and spreads to th rest of the body.

Estimates very on the percentage of ticks that are infected with the disease, but they generally range between 1 to 5 per cent. According to Dr. Lawrence Frenkl of Georgetown University, "Virginia is one of the country's most heavily tick-infested areas."

Dr. Grayson Miller of the Virginia Bureau of Epidemiology said conditions in Virginia are "deal for ticks." He cited high population density and warm weather as likely contributors to the high disease rate in the state.

Reported cases of Rocky Mountain spotted fever have been increasing steadily over the last several years all over the country. Miller and Dr. William Winkler of the Center for Communicate Diseases inAtlanta attribute this at least in part to a ban on pesticides such as DDT, which they say are more effective against ticks than the available pesticides.

Winkler also said that an upsurge of interest in the disease has probably led to more cases being reported, not necessarily reflecting a real increase in the number fo persons contracting the disease.

Winkler said that as far as he knew, no serious research was being done into ways of eradicating the small but extremely tough ticks, which burrow head first into the skin of warm-blooded animals and feed on their blood.

He said "a vaccine is now available, but it is not what we would regard as the perfect vaccine." The problem, he continued, is getting the patient to a physician quickly, identifying the disease and treating it immediately.

The two deaths in Virginia both occured this month. The epidemiology unit would not divulge the names of the victims. The person who died in Culpeper was reported to be a 19-year-old male.