Plucked from their classes or turned away at school doors, students who had not met new vaccination requirements flooded the Allegheny County Health Department in Oakland by the hundreds yesterday, some waiting in line for hours to get their shots.

Among them were procrastinators, holdouts, busy ones, and ones who just forgot.

One of them was Marta Kolb, 14, of Bloomfield, who was met by school officials and a nurse at the doors of Pittsburgh International Baccalaureate 6-12 yesterday.

"They said, you've just got to go back home or get your vaccines before you can come back," said Marta, a ninth-grader. She and her mother, Traci, ran errands to take the edge off the long wait, made worse by Marta's fear of needles.

"You'll be scared once you see the needle, very scared," said Patricia Thompson, 13, of Pittsburgh CAPA, who waited three hours to get two shots. "The pain goes away pretty fast."

The county required students in all public schools -- including cyber and other charter schools -- private schools, and home-schooled students to have the required shots on record or present a waiver for religious or medical reasons by yesterday. The list of shots includes several newly required vaccinations.

"Students have been officially excluded, and once they submit documentation they will be readmitted," said Pittsburgh Public Schools spokeswoman Ebony Pugh. "The last thing we want to do is keep students out of school, but this is a mandate, and we are going to follow it."

By the end of the day, 2,100 students districtwide lacked vaccines, Ms. Pugh said, about 800 of whom are in the high schools.

In addition to shots long required, the county mandated that students receive immunizations or a waiver for chickenpox, meningitis and a combination vaccine known as Tdap that includes tetanus, diphtheria and pertussis (whooping cough).

Out of the 180,000 students in the county, health officials estimated that 2 percent of them, at the most, had not shown proof as of yesterday. Those numbers are down from about 30,000 this past spring and 60,000 from last fall, said department spokesman Guillermo Cole.

Mr. Cole said the Oakland clinic, which provides free immunizations, had been seeing about 250 kids each day since mid-August. During the week of the deadline, however, the clinic serviced 2,100 students in a three-day span.

"We estimate that in the month of September, we will vaccinate well over 5,000. That's putting a dent in the number of unvaccinated children," Mr. Guillermo said.

These vaccinations have kept both clinics and schools busy.

"We're getting records in by the second. It's nonstop with students coming in just completing their shots ... This has dominated most of my day today," Dr. Jennifer Murphy, principal of Pittsburgh Carrick High School, said yesterday.

Her school has about 900 students, and she said that in a matter of a week the number of unvaccinated students went down from more than 300 to less than 100.

She said she expects all of her students to be back by Monday. They will be allowed to make up homework just as if it were a regular absence.

"The counselors have been working nonstop on this for the last two days," she said. "We're working really hard to get this thing going."

Of the 28,000 students across the 66 schools in the city of Pittsburgh, more than 11,000 students didn't have their vaccination record updated in June. This week, that number went down to less than a thousand, Ms. Pugh said.

She said that in city schools, most of the cases came from the high schools. Part of that is because meningitis and Tdap vaccinations are required only for grades 7 and higher; part is because high schools have large student populations.

The Duquesne City School District, which has one school for students from kindergarten through eighth grade, reported 135 students of 437 enrolled without the required shot records. In contrast, Fox Chapel Area School District, which has roughly 4,500 students, reported 29 who were held from classes, less than 1 percent.

Most of the schools districts were still updating their compliance numbers on deadline day, making it difficult to gauge the exact number of students who failed to meet the mandate.

For example, at the beginning of the school day yesterday, Chartiers Valley School District had about 150 students who needed to turn in their records. Later that afternoon, district spokesman Chuck McCartney said the number was down to 92.

Several places reported 100 percent compliance, including the Diocese of Pittsburgh, which has 86 Catholic schools across Allegheny County.

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