Edward Hospital in Naperville says, for now, there will be no visitors under the age of 18. Adventist Hospital in Bolingbrook along with Glen Oaks Hospital, Hinsdale Hospital and LaGrange Memorial Hospital are all restricting visitors. Children's Memorial Hospital is also prohibiting people under 18 or individuals with flu-like symptoms from visiting patients.
Meanwhile, the federal government says the swine flu vaccine outlook is improving. Twenty-two million doses are now available.
The limited vaccine supply has frustrated Americans who have stood in lines for hours in some parts of the country, including Kane County.
Health officials are promising it will soon get easier to find and receive the vaccine.
"We're still using technologies that have been around for a long time. That's good news in terms of safety. We're not cutting any corners. We're not trying anything that's new or experimental in this season. But we wish we had vaccine technologies that could be quicker," said Dr. Thomas Frieden, CDC.
The vaccine is grown in eggs in what officials say is a reliable but slow process. For the H1N1 vaccine, smaller amounts were being produced per egg than expected.