About a million Americans have HIV or AIDS and it’s estimated a quarter of them don’t know it. Iowans who are at-risk for the potential-killer disease are encouraged to find out if they’re infected during today’s National AIDS Testing Day.

Katie Noynaert, a disease prevention education coordinator at the central Iowa chapter of the American Red Cross, explains who should get tested. "An at-risk individual would be an injection drug user or anyone who’s had unprotected sex," Noynaert says.

Hospitals, clinics, county health departments and other locations statewide are offering the tests today, which in most cases are free. Noynaert says getting tested is a painless process. She says you’ll talk with a counselor first about your risk factors, then an oral test will be done — just a swab inside your mouth — with the results in 20 minutes. If your test is negative, you’ll be counseled on how to remain that way. If you’re positive, a second, more definitive, test will be done, the results of which will come back in two weeks.

According to Noynaert, it’s vital that people who are at-risk be tested. "It is greatly important to get an HIV test done if you have engaged in any risky behavior in the past," she says. "About 25 percent of people who have HIV don’t know that they have it so they’re still able to spread it, not knowing that they’re spreading the disease."

In Iowa, the latest figures indicate about 1650 people have AIDS, ranking 39th highest among the 50 states.