Most U.S. high school students and young adults who have sex don't get HIV tests, according to a new report from the Centers for Disease Control and Prevention.
On average, just 22 percent of high school students and 33 percent of young adults aged 18 to 24 who report ever having sexual intercourse also report being tested at least once for HIV, researchers report in the journal Pediatrics.
"Adolescents and young adults face multiple barriers to HIV testing," said lead study author Michelle Van Handel, a scientist specializing in HIV/AIDS prevention at the CDC in Atlanta.
For example, she said, young people often lack access to confidential healthcare services, and their poor knowledge of sexual health may lead them to underestimate their risk for HIV infection.
Also, healthcare providers might not realize that in 2006, the CDC recommended that all people aged 13 to 64 be tested for HIV.
To see whether testing programs since then resulted in any increase in HIV screening among sexually active youth, Van Handel and colleagues analyzed data collected on high school students from 2005 to 2013 as well as records on young adults gathered from 2011 to 2013.
Among high school students, no change was detected in HIV testing prevalence over the study period for this group, regardless of gender or race, the analysis found.
For young men aged 18 to 24, there also weren't any significant changes in testing habits over the study period for this group, with 27 percent on average reporting at least one HIV test.
Screening decreased significantly for young women, dropping from about 42 percent to 40 percent overall. Testing declined from 37 percent to 34 percent for white women, and from 69 percent to 60 percent for black women.
The results are troubling because 44 percent of adolescents and young adults with HIV don't realize they have it, the highest percentage of any age group, the researchers note. Without testing and diagnosis, they can't get treatment that may improve their own health and also lower the risk of transmission to others.
Declines in screening for black women and the lack of gains for young men are particularly problematic because these groups have higher risk of HIV infection than other young people, the researchers also point out.
The results highlight the need to get more teens and young adults screened, said Ann Kurth, dean of the Yale College of Nursing in Orange, Connecticut.
Access, affordability and confidentiality are big hurdles for young people, said Kurth, a certified nurse midwife who has studied HIV screening efforts in the U.S. as well as in Africa.
"Access to anonymous testing can make a big difference for young people," Kurth added by email.
Parents, educators and clinicians can also do a better job of talking to teens about sexual health, and starting these conversations at an early age before sexual activity begins.
"The main point for parents is to let your teen or child know that you are there to listen and to help, and not necessarily expect them to initiate the conversation," Kurth added. "Adolescents who feel they can talk to a parent tend to have better statistics in terms of partner selection and protection against HIV and other sexually transmitted infections."