DENVER (AP) -- Some Colorado health care providers are running short of flu vaccines because of a spike in the number of people being hospitalized with the illness.

Kaiser Permanente, which has hundreds of thousands of members along the Front Range, stopped giving out flu shots this week and may not resume until Friday, when new shipments are expected to be delivered.

According to the Denver Post, more than 500 people have been hospitalized in Colorado so far this season.