Almost 90 percent of sexually active college students contract a sexually transmitted disease and are not even aware of it, local experts say.Among the 20 million Americans who have genital human papillomavirus are the high percentage of sexually active college women and men, said Dr. Jayanthi Lea, a gynecologic oncologist at University of Texas-Southwestern Medical Center.

“I would venture a guess between 70 and 88 percent,” Lea said.

The TCU Health Center refused to discuss HPV prevalence on campus with the Skiff, but according to the Centers for Disease Control and Prevention, results from a 1998 study show more than one in 10 college women become infected with genital HPV each year. Conductors of a 1996 study found anywhere from 28 percent to 46 percent of females under 25 have the virus.

According to a CDC fact sheet, no less than 50 percent of sexually active males and females will contract genital HPV during their lifetimes. About 80 percent of women will get the disease by the age of 50.

Lea said many cases do not produce any symptoms and the immune system clears most HPV infections, which attributes to the prevalence of the disease.

“First of all, it’s so prevalent because it’s a sexually transmitted virus,” she said. “There’s no way to protect against HPV.

“A lot of people have it and have no idea they have it.”

Lea said a number of these cases could be cut down by a new vaccine.

Gardasil, a vaccine developed by Merck & Co. Inc., has proven effective against the four most common types of genital HPV, she said.

These types include HPV-6 and -11, which cause 90 percent of genital warts, and types 16 and 18, which are responsible for 70 percent of cervical cancer cases, Lea said.

“We can anticipate a huge reduction in HPV-16 and -18, also 6 and 11,” she said.

Suzy Lockwood, a Harris School of Nursing assistant professor, sits on an expert panel that discusses how the three-dose vaccine should be administered in Texas and said Merck’s ongoing phase III trial has produced positive results.

“Gardasil prevented 100 percent of high-grade cervical pre-cancer and non-invasive cancer associated with HPV 16 and 18,” Lockwood said.

According to a Merck press release, the randomized study involved more than 12,000 women, ages 16 to 26, half receiving placebos and half receiving the vaccine. Over a time period of about 17 months, no cases of high-grade pre-cancer and non-invasive cancer from HPV types 16 and 18 were reported among vaccine group women; 21 cases developed among the women who received the placebo.

Lockwood said since so many younger people have the virus, the biggest debate is at what age to administer the vaccine, in childhood or in adulthood.

“Unfortunately there are a lot of young women who start having intercourse at 11 or 10,” she said.

If HPV goes undetected, it can lead to cervical cancer – a cancer most fatal among North Texans than any other Texas region’s residents – Lockwood said.

“One of the hugest risk factors for developing cervical cancer is lack of screening,” she said.

Pre-cancerous HPV cells are found through Pap tests, which will still be necessary even with the vaccine, she said.

“Just because you have this vaccine doesn’t mean you can’t get cervical cancer,” Lockwood said.

“There are other things that cause cervical cancer,” she said.

Of 30 sexually transmitted types of HPV, 10 cause cervical cancer, according to the CDC fact sheet; the vaccine is designed to combat four types of genital HPV, which leaves six HPV types unprotected.

All types of HPV can cause abnormal Pap smears, but most are not detrimental, according to the fact sheet.

Lockwood said Gardasil has not been approved by the Food and Drug Administration or the Advisory Committee on Immunization Practices but is expected to come out sometime in 2006.