The flu outbreak at the Martha’s Vineyard Regional High School appears to have subsided this week, but the majority of Island children still have not been immunized against swine flu, because local health authorities cannot secure enough vaccine.

And the all-Island clinic held on Wednesday to vaccinate people against seasonal flu, planned to run four hours, was ended after just two when supplies of that vaccine also ran out.

As of late yesterday, authorities said, the state had been able to offer no further doses of vaccine for the seasonal flu, and had promised just 100 doses of vaccine for the H1N1, swine flu — not enough to allow them to continue their school immunization program.

Before they ran out on Wednesday, the clinic inoculated 1,226 adults against the seasonal flu, as well as 99 volunteers, firefighters, EMTs and police, done the previous day.

High school principal Stephen Nixon said attendance this week had been above 90 per cent for three consecutive days, a rate he said was normal. As a result, he had decided to lift a restriction on gatherings of more than 25 students.

At its worst, 140 of the school’s 700-odd students had been absent on a single day, and absences averaged more than 100 a day last week.

“We only sent two home today,” he said yesterday. “I won’t say it’s over, but it’s definitely in a lull.”

The bad news is that federal and state agencies still cannot produce and distribute enough vaccine for either of the two strains of flu to meet demand, meaning the majority of Islanders remain unprotected.

Bob Tonti, the chief executive officer of the Vineyard Nursing Association, said he had received word from state health officials that 100 further doses of swine flu vaccine would be made available in the next few days.

“But we don’t know if it is a mist, or injectable vaccine. We won’t know until we get it. They’re making it harder than it needs to be,” he said, explaining that some people with respiratory conditions like asthma, or other health concerns, could not be administered the mist.

“And with just 100 doses, I doubt that we will be able to do any more schools,” Mr. Tonti said.

“You don’t start a school and then just do it partially.”

The only way another school clinic could take place, he said, would be if a majority of parents declined to have their children immunized.

“All the schools will tell us by tomorrow [Friday] how many parents said yes to immunization. So maybe if we had a school of 300 children, and only 100 parents said yes, we might be able to do that,” he said.

So far students at three schools — the Chilmark, West Tisbury and Public Charter School — have received a single dose of H1N1 vaccine. Children under age 10 need two doses, but he said second doses would have to wait until all children had received a first dose.

“So we have a whole bunch of complications,” Mr. Tonti said.

“We just have to get more, quicker.”

The H1N1 virus is considered a greater risk to young people, hence the focus on school clinics. The regular flu is considered a greater threat to older people, particularly those over 50.

Wednesday’s all-Island clinic was considered a success, as far as it went. This year for the first time, authorities tested a new system where people first drove to two staging areas, at Waban Park in Oak Bluffs and the Agricultural Hall in West Tisbury

Things went reasonably smoothly, although there were some delays for those who arrived early.

Ron MacLaren, spokesman for the Martha’s Vineyard Public Health Coalition, a group comprising the various town health agents and representatives of the hospital, Vineyard Nursing Association, emergency management and the Wampanoag tribe, said people arrived at staging points before 6 a.m.

“People were lining up an hour before the staging area even opened,” he said.

“That isn’t new; we’ve always had people showing up early in the past. But I do think more people made a concerted effort to be earlier this year, knowing supplies were short.”

This meant long waits — two hours or more, for the early birds, because the clinic itself, at the regional high school, did not begin until 8 a.m.

“But at least they definitely would have gotten the vaccine,” Mr. MacLaren said.

The staging area began turning people away at 10 a.m.

“We will wait for the rest of our seasonal vaccine to come in, and when that arrives we’ll be putting out further notices about how we will be able to give that out,” Mr. MacLaren said later.

Those who missed out on Wednesday were given information on how to obtain vaccine when more became available.

A list has been started so those people can be contacted if and when it arrives.