In another sign that vaccine supplies aren't keeping up with demand, HealthPartners has temporarily suspended plans to hold walk-in clinics for seasonal flu shots.

HealthPartners had scheduled 31 walk-in clinics in September and October, but decided to halt them after completing only two, said spokesman Joe Dangor. He said vaccine shipments have slowed because manufacturers are concentrating on producing vaccine for H1N1, or swine flu. "So we haven't gotten our full supply of seasonal flu vaccine, and that's why we're running low," he said.

The University of Minnesota also postponed two planned flu-shot clinics on campus this month, citing delays in seasonal vaccine shipments.

State officials say some clinics are running low on flu shots because of the decision to start vaccinating earlier than usual.

Kris Ehresmann, who heads the vaccine program at the Minnesota Department of Health, said manufacturers have shipped some 54 million doses of vaccine for seasonal flu nationwide. "That's really fabulous for this time in September," she said, adding that it's about half the annual supply.

Normally, clinics don't start offering flu shots until mid-October, and they get more supplies throughout the fall. But this year, the combination of an early start and huge demand has led to spot shortages.

"We basically moved up our whole seasonal influenza campaign by a month," Ehresmann said.

Health officials have encouraged people to get seasonal flu shots before the H1N1 vaccine starts arriving next month.

Meanwhile, HealthPartners will continue to give seasonal flu shots to patients during scheduled appointments or regular clinic visits, the company said. It plans to reschedule the walk-in clinics when more seasonal-flu vaccine arrives.

To find a flu-shot clinic, go to www.mdhflu.com.

Maura Lerner • 612-673-7384