Fairfax County school officials suspended preschool and kindergarten students yesterday because they have not been immunized against the measles, diphtheria, tetanus, whooping cough or polio.

While the number of pupils suspended represents only 2 per cent of the 7,000 preschool and kindergarten students in Fairfax, the suspensions were the most graphic examples yet of Washington-area school officials' efforts to prevent an epidemic like the measles that many students contracted during the last school year.

Students in grades one through 12 in Fairfax have until Dec. 9 to show proof of immunization against the communicable diseases or they also will face suspension. Loudoun County students must show proof of immunization by Jan. 3 or they will be suspended. Prince William and Arlington county students were required to show proof of immunization on the first day of school in September, while Alexandria school officials have not yet set an immunization deadline.

Secondary students in Maryland have until Thursday to prove that they have been immunized against measles or they will be sent home. Elementary school students in Maryland have already been immunized against measles, health officials reported.

District of Columbia school officials said they have been urging parents to have their children immunized against the communicable diseases, but have not set an inoculation deadline.

For the past few months, Washington-area school officials have sent letters to thousands of parents telling them that their children lack proper immunization and warning them that if their children were not inoculated they would be suspended.

School officials stressed the immunization programs after an outbreak of rubeola or red measles, which can lead to pnuemonia or encephalitis in the Washington suburbs last school year. Fairfax officials alone reported more than 600 cases of measles from January to August, with most of the cases occurring in the 10-to-14 age bracket.

In Maryland, 718 cases of measles were reported last school year. A study showed that one-third of the 470,000 students in the seventh through 12th grades in Maryland were not immunized against the measles.

School and health officials said the majority of the measles victims were students immunized too early in their lives or with ineffective vaccines.

A Fairfax school spokesman said that in September officials identified 30,000 students who lacked proper immunization. School officials "guesstimate" there still are 25,000 students who must show proof that they have been immunized.

The Fairfax spokesman said parents of the 140 children suspended yesterday were telephoned and asked to come and pick up their children. Most of whom are bused to school. In some cases where parents could not be reached, the spokesman said the children were allowed to stay in school, but a note saying the child couldn't return until he showed proof of proper immunization was sent home with the child at the end of the school day.

In Montgomery County, school officials estimate that 5,000 of their 57,653 secondary school students have not been immunized against the measles. Prince George's County school officials sent certified letters last week to the parent s of 1,500 students warning them that their children have until Thursday to show proof of inoculation against measles.

In Loudoun, school officials have sent letters to parents of 1,000 students warning them that their children are not in compliance with the state immunization law.

Under Virginia law, children entering school for the first time must show proof of immunization against diphtheria, tetanus, whooping cough, poliomyelitis, red measles, rubsola and German's measles (rubella).

But the law, which has been in effect since July, 1972, hasn't been strictly enforced in some jurisdictions, school and health officials said. "The measles epidemio (last school year) brought enforcement to the forefront," said Dr. Marjorie Hughes, chief of school health services for Arlington.

She said 210 Arlington students were sent home the first day of school this year. "It took about two weeks for everyone tocome back," she said.