Grief counselors were at Abraham Lincoln High School in Council Bluffs Monday to help students and staff deal with the sudden death of 15-year-old Ashley Andreasen, who died Friday night after contracting meningococal meningitis.

It's not yet known where the sophomore picked up the infection. She began showing symptoms last Thursday. Because of the timing with winter break, other students should not have been exposed.

Chelsie Ruiz is one of many AL students dealing with the death of a classmate and friend. "We were all kind of freaking out, but then we all kind of talked about it in fifth hour it kind of settled it."

The bacteria invaded her body and killed her just hours after she showed symptoms. In a letter sent home with students, the school assured parents that the deadly bacteria potentially present before the student's break would no longer be a threat two weeks later.

"We can go back and school was not in session at that time and so from that standpoint we don't have to worry about anybody catching the disease that was in the school,” says Pottawattamie County Director of Public Health Donn Dierks.

He says anyone who had close contact with Andreasen over the break should see their doctor.

"From a public health standpoint we feel pretty comfortable at this time that all of the close contacts have been contacted and we follow up with that to make sure they receive their proper antibiotics."

Symptoms appear up to 10 days after infection and include fever, headache, vomiting and neck stiffness. Meningitis is spread by sneezing and coughing.

Andreasen's friend Samantha Anderson says the mood around school is somber. "It's just really surprising is that this happened so fast and no one really knew that she had it. I was really sad and I just can't believe that she's really gone."