Children under 18 won't be allowed in Wyoming Medical Center's pediatrics and birth units, the hospital announced Friday.

The decision comes amid high flu activity throughout Wyoming that state health officials say is almost 100 percent due to the swine flu, or H1N1, virus.

The restriction, which is in effect until further notice, includes siblings of hospitalized children and newborns.

"Children and young adults are more susceptible to the H1N1 flu and tend to spread infection more easily," Kristi Keller, the nurse manager for women and children's health, said in a statement. "Young patients, pregnant women and newborns are more vulnerable to infection. We must take every precaution to protect them while they are under care."

Hospital officials are asking children to avoid visiting other parts of the medical center.

The hospital is currently experiencing an increase in the number of patients who are coming to the emergency room with flu-like symptoms, said spokesman Shauna VanderLinden.

The emergency room usually sees about 100 patients a day. In the past week, that figure has reached 140 on some days.

To help limit the spread of flu, the hospital has set up stations with surgical masks, tissues and hand sanitizer. Officials are encouraging patients to use hand sanitizer whenever they enter or leave the building or a patient room.

Reach crime reporter Joshua Wolfson at (307) 266-0582 or at josh.wolfson@trib.com. Visit tribtown.trib.com/JoshuaWolfson/blog to read his blog.