New guidelines by the U.S. Preventive Services Task Force (USPSTF) is calling for all Americans aged 15 to 65, to get tested for HIV regardless of whether they are considered to be at high risk. The move aims to remove the stigma associated with HIV screening.

The Centre for Disease Control and Prevention (CDC) estimates that almost 1.2 million people in the United States are infected with HIV, but as many as 25 percent of them are unaware. The percentage is much higher among teenagers and young adults - about 60 percent. About 50,000 people become infected in the United States each year, according to the report.

The guidelines were released following a number of cases in which early treatment along with a combination of strong antiretroviral drugs notably improved patient survival rates. A recent study showed that HIV treatment can reduce transmission of the virus to an uninfected partner by as much as 96 percent.

"HIV is a critical public health problem, and there are still 50,000 new infections per year," said Dr. Doug Owens, a task force member and professor of medicine at Stanford University. "There's very good evidence that treatment is effective when given earlier, at a time when people are often asymptomatic. So the only way they would know that they had HIV, or that they needed treatment, is to be screened."

Until now, the task force had recommended HIV screening only for people in these risk groups and for pregnant women. High-risk groups include those who have sex with gay or bisexual men, drug users and economically disadvantaged populations in which HIV rates are high.

The new statement was published online Monday on the task force's website and by the Annals of Internal Medicine. The new guidelines from the government-backed panel of doctors and scientists now align with longstanding recommendations by the CDC.