By the time four H1N1 vaccination clinics opened at 10 a.m. yesterday, Allegheny County Health Department officials already were nervous, even scared.

Lines curling around each of the buildings at Chartiers Valley, North Allegheny, McKeesport and Pittsburgh Schenley high schools numbered 1,000 or more people. Each site, open until 4 p.m., had only 2,700 available doses of vaccine, although backup supplies were available should they run out.

"The line was amazing. It was incredible," said Sharon Silvestri, chief of the health department's infectious diseases program and medical operations lead at Pittsburgh Schenley. "I was like, whoa."

One man on his cell phone at Chartiers Valley could be heard complaining, "This is an all-day line, not just an hour. I'm not waiting."

By mid-afternoon, however, officials were relieved to see dwindling lines, especially once they realized they had sufficient doses to immunize everyone there.

Despite the lines, the day generally went smoothly with the health department immunizing thousands of people, including multitudes of children. Dr. Bruce W. Dixon, health department executive director, said each clinic averaged about 200 vaccines an hour with people waiting for no more than two hours.

"No one passed out. There were no fights. We didn't see any line jumpers. And most of the people were very mannerly," he said, noting his department ran a trial run last weekend in Oakland by immunizing 400 pregnant women.

By closing time yesterday, the county had not depleted its vaccine supply and anticipates more shipments in coming weeks, Dr. Dixon said. The department will tally doses administered at the clinics before deciding whether to schedule more clinics. The other option is to offer H1N1 vaccinations only at its immunization clinic at 3441 Forbes Ave., Oakland.

Despite the day's successes, passions were growing early in the day as the line snaked around Chartiers Valley High School -- from auditorium entrance to the visiting-team bleachers at the football field.

"They will have a riot on their hands if people wait for two hours, then they say they have no vaccines," said Chip Kirksey of Mt. Lebanon, who was in line to have his 9-month-old daughter, Lola, vaccinated.

Only people in five at-risk categories qualify for the vaccine at this time. They include: children 6 months to 24 years old; people who live with or care for children under 6 months old; pregnant women; health care and emergency medical services workers; and people 25 to 64 with underlying medical conditions.

Some people who arrived more than an hour before the clinics opened still had a considerable wait. But few people voiced complaints.

"I thought we'd be toward the back of the line but now we're near the front," said Dr. Cory Nordman of Baldwin-Whitehall, whose wife, Dr. Bethany Nordman and their 1-month-old son Noah waited in the car while he waited in line with his cell phone. He and his wife doubly qualified for the vaccine as health care officials and caregivers of a child under 6 months of age.

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