"Nobody will be surprised if someday it is recommended for boys, but it's premature to make that call now," Wyand said. "The early returns I'm aware of with boys are positive. The vaccine appears to trigger an immune response similar to that of girls."
Gardasil isn't the only development on the vaccine front -- other vaccines for sexually transmitted diseases are being studied as well, Temte said. A second HPV vaccine, this one from GlaxoSmithKline, is currently awaiting FDA approval, he said.
And researchers are also looking at a vaccine that could prevent herpes simplex, the cause of genital herpes. "There are going to be a few years out before we see anything like that," Temte said.
Other news involving sexually transmitted disease is less encouraging.
The CDC estimates that approximately 19 million new sexually transmitted infections occur each year, almost half of them among young people ages 15 to 24. Direct medical costs associated with STDs consume up to $14.7 billion annually in the United States.
And, in 2006, there were increases in chlamydia, gonorrhea, and syphilis in the United States, according to the CDC.
More than 1.03 million cases of chlamydia were reported in 2006, up from 976,445 in 2005. Gonorrhea has increased for two years in a row, following a 74 percent decline in its reported rate for two decades. And the national syphilis rate increased 13.8 percent between 2005 and 2006, again reversing what had been years of decline.
Doctors are investigating what these increases mean, Wyand said.
"They aren't sure if those were true increases, or if people are being tested with better and more specific technologies," he said, noting that each of the STDs tend to be chronically underreported.
To learn more about sexually transmitted diseases, visit the American Social Health Association.
SOURCES: Fred Wyand, spokesman for the American Social Health Association, Research Triangle Park, N.C.; Jonathan L. Temte, M.D., Ph.D., associate professor in the Department of Family Medicine at the University of Wisconsin School of Medicine and Public Health, and the American Academy of Family Practitioners' liaison to the Advisory Committee on Immunization Practices; U.S. Centers for Disease Control and Prevention, Atlanta