MADISON, Wis. -- Every year, 2.8 million Americans are diagnosed with chlamydia.

The ailment is the most commonly reported sexually transmitted disease in Madison and the United States, health officials said.

Chlamydia is often known as a silent disease because 75 percent of infected women and about half of infected men have no symptoms, WISC-TV reported.

Any sexually active person could be infected with chlamydia, but someone with a larger number of sex partners has a greater risk of becoming infected, according to health officials.

"Women will generally get a vaginal discharge and they'll note a vaginal odor," said Meriter WomanCare nurse practitioner Jill Winters. "Sometimes, they will actually have bleeding in between menstrual periods or heavier cramping periods. Men will have a discharge and maybe some urination as symptoms, but again, it's more common to not have symptoms, which is a problem."

Officials said that the best way to find out if a person is infected with chlamydia or any other sexually transmitted disease is to be tested.

Doctors could get results by performing a simple pelvic exam for a woman and genital exam for a man.

A primary health care provider can do the testing, which is covered by health insurance.

A person without health insurance could be tested at Planned Parenthood, Blue Bus Student Health Clinic and the Madison Community Health Center.

Antibiotics will get rid of the infection and prevent transmission, official said.