The "kissing disease" is spreading its love around campus.

Since classes began in September, 551 cases of mononucleosis, or mono, have been reported to University Health Services (UHS).

"Mono is a fairly common illness among college students," Beth Collitt, marketing director at UHS, said. "We see a few cases every week."

According to a mono fact sheet on the UHS Web site, mono -- commonly called the "kissing disease" -- is spread by saliva. However, few students realize that mono can also spread through coughing and sneezing, Margaret Spear, UHS director, said.

Penn State alumnus Tom Flack said he had a roommate in college with mono, and he only partially protected himself.

"I just knew not to drink out of any cups he was drinking out of or touch his Kleenexes," Flack said.

The close proximity of students, especially in the winter, makes them more susceptible to getting mono, said Dr. Evan Bell, an infectious disease expert at Centre Medical and Surgical Associates. "It may be more common in the winter months because people are more often in close quarters," Bell said.

Getting enough sleep, eating well and washing hands are among the "common sense" ways to avoid mono, Spear said.

Typical symptoms include fever, swollen lymph nodes, a bad sore throat and fatigue, Bell said. Infected students may also have muscle, body ache and nausea and will feel as if they have a virus, he said.

Bell said symptoms may last several weeks to a month, and fatigue can last up to six months. According to the UHS Web site, the normal incubation period for mono ranges from 30 to 45 days.

Kristen Kutz (sophomore-English) said her sister had "all the clinical symptoms" of mono. "She was really sick," Kutz said. "She was really sleepy and threw up a lot."

Bell said people with mono should avoid physical activity and contact sports because a hit in the abdomen could rupture the enlarged spleen. Also, because of the effects of alcohol on the liver, those with mono are advised to abstain from drinking.

He added that mono, caused by the Epstein-Barr virus, can be accurately diagnosed by a blood test. Though no cures are available for mono, people with severe sore throats may be given steroids to reduce the swelling.

Bed rest and increased fluid intake might help patients recover faster, but patients should also refrain from kissing and close intimate contact, Bell said.

Derrick Lampkin, a geography professor, said mono is a popular excuse used by students for missing classes and assignments. "It's hard to discern if mono being cited as a valid excuse is real or fabricated," he said.

Lampkin said he encourages all his students who are truly ill to seek medical help and get documentation.