Scientists at Stanford University are developing a spit test for HIV that is between 1,000 and 10,000 more sensitive than ones currently available.

A report published in the Proceeding of the National Academy of Sciences (PNAS) indicated that in a study of four dozen patients, the new test was 100% accurate. If those results are replicated among a significantly larger sample size, researchers say it will be an important tool in the fight to end HIV.

There are multiple oral fluid HIV tests on the market, but the new method is reportedly able to detect the virus two weeks after exposure.

Spit is actually a more ideal method of testing for HIV than blood: The virus can't be transmitted through saliva and the method of collection is cheaper and much less invasive. But the level of HIV antibodies is incredibly low, which is why researchers have struggled with an accurate spit test so far.

Stanford chemist Carolyn Bertozzi has been able to turn antigens carrying the virus into a DNA signature that can be amplified and identified. In theory, the technique could also be used to screen for other illnesses, including measles.

Bertozzi hopes to bring the oral HIV test to market in the next 18 months.