Even when serious emotional problems are detected, university officials often feel constrained in how they respond due to an array of laws and policies that protect students' rights and privacy.
"The number of people coming to colleges who've had psychiatric treatment has increased tremendously," said Dr. Gerald Kay, a psychiatry professor at Wright State University and chair of the American Psychiatric Association committee on college mental health.
"Now they're able to come to college — that would not have been the case earlier," he said. "You've got a very large number of people who may have some vulnerabilities. It has stressed the availability of resources."
Reasons for the surge include the Americans with Disabilities Act, which gives mentally ill students the right to be at college, and increasingly sophisticated medications that enable them to function better than in the past.
Recent surveys and studies underscore the scope of the increase.
A survey last year by the American College Health Association found that 8.5 percent of students had seriously considered suicide, and 15 percent were diagnosed for depression, up from 10 percent in 2000. The Anxiety Disorders Association of America found that 13 percent of students at major universities and 25 percent at liberal arts colleges are using campus mental health services.
Dr. Chris Flynn, director of Virginia Tech's counseling center, has declined to discuss details of gunman Cho Seung-Hui's case, but said the center's staff — which includes a psychiatrist and 11 psychologists — treats about 2,000 students per school year.
In December 2005, a magistrate ordered Cho to undergo an evaluation at a private psychiatric hospital after two women complained about annoying calls from him and an acquaintance reported he might be suicidal. An initial evaluation found probable cause that Cho was a danger to himself or others as a result of mental illness, but court papers indicate he was free to leave the hospital within days — a step allowed only if hospital officials judged him no longer a danger.
"We have to provide services to students with mental illness — it's not grounds to exclude them from our property," Flynn said. "We cannot discriminate against the mentally ill, nor do we want to."
He said the type of complaints lodged against Cho by the two women are a common and challenging phenomenon on campuses nationwide.