HIV testing for all Americans is now covered under Obamacare, because it's been declared a form of "preventive care" - in the same way as birth control.
That's come about because the US Preventative Task Force, a government panel of medical experts, has recommended HIV testing for every American aged 15 to 65.
The Affordable Care Act mandates that insurers cover all of the preventative services that are recommended by the Task Force. Hence regular HIV testing will now be free for all Americans under Obamacare.
In addition, Obamacare's pre-existing conditions rule means that thousands or perhaps millions of Americans living with HIV and AIDS will now be able to get health insurance, whereas they struggled to do in the past. The rule against lifetime caps on coverage will also help sufferers with HIV.