Community Health Services Director Liz Stark says the 400 to 500 doses will be distributed this week to physicians around the county. Stark says the county has been receiving small shipments the last five weeks and has distributed about 800 doses so far.

The vaccine is being given first to high-risk groups, including pregnant women, children and health care workers.

The state has received about 250,000 doses so far, but it hasn't been enough in some cases. Denver Health Medical Center announced last week that it would have to cancel 17 of 19 planned flu vaccine centers this month because of a vaccine shortage.