As the number of procrastinators dwindles, school officials across Allegheny County today are under orders to turn away students who haven't met new vaccination requirements.

County Health Department spokesman Guillermo Cole said the number of holdouts has fallen steadily since August and dropped sharply this week, with students streaming into the department's free clinics for the shots.

"We've done well over 5,000 since late August," including 503 Monday and 720 Tuesday, Mr. Cole said. He added that unknown numbers of students also are being vaccinated at doctors' offices and having documentation faxed to schools.

Mr. Cole estimated that 1,000 to 2,000 students countywide may be out of compliance this morning, down from an estimated 7,000 six weeks ago and as many as 30,000 last spring.

But Pittsburgh Public Schools spokeswoman Ebony Pugh estimated that 3,600 in the city alone remained out of compliance.

Those figures exclude students who received vaccination exemptions for personal, religious or medical reasons.

Districts said students out of compliance today would be sent home or isolated until parents come for them.

Today and tomorrow, the county's walk-in clinic at 3441 Forbes Ave. in Oakland will stay open until 7 p.m. -- three hours later than usual -- to accommodate students who still need the shots.

The regulations affect about 180,000 students -- public, private, parochial and home-schooled.

Mr. Cole estimated that fewer than 1 percent countywide would seek exemptions; Ms. Pugh estimated that as many as one-third of city students would do so.

The new regulations, enacted by the department and County Council, require a second dose of chicken pox vaccine -- or proof a child had the disease -- for all students in kindergarten through grade 12.

Other requirements include meningitis and "Tdap" -- tetanus, diphtheria and whooping cough -- vaccines for students in grades seven and above.

Children receive multiple doses of tetanus and diphtheria as they age. The Tdap provides a booster to secondary students. This is the first time the county has required meningitis and whooping cough vaccines.

The requirements initially were to take effect at the start of the 2008-09 school year, but the deadline was pushed back to last spring and then today. Districts said they've made numerous efforts to inform parents of the requirements.

"The eighth and final notice went out this week," said Teresita Kolenchak, spokeswoman for Penn Hills School District.

About 460 Penn Hills students remained out of compliance yesterday, down from about 640 Monday, she said.

In Woodland Hills School District, about 400 to 450 students remained out of compliance late yesterday, down from about 1,200 at the start of the school year, spokeswoman Maria McCool said. She said so many families sent in proof of vaccination yesterday that the ink cartridge in a fax machine had to be changed.

South Allegheny School District, which imposed a vaccination deadline at the end of the last school year and held report cards from procrastinators, had one child out of compliance yesterday.

The North Hills and Moon Area districts said they had 25 and 89 students out of compliance, respectively.

McKeesport Area School District spokesman Jason Davidek said fewer than 10 percent of the district's 4,300 or so students were out of compliance, with the number "dropping like a lead balloon."

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