The rate of HIV infection among intravenous drug users (IDUs) is increasing globally, according to a new study reported on by Reuters.

As many as 3 million IDUs are living with HIV worldwide; these new statistics are based on peer-reviewed studies and data from U.N. agencies and global experts. Researchers identified IDUs in 148 countries and revealed that HIV prevalence among them was more than 40 percent in nine countries: Estonia, Ukraine, Myanmar, Indonesia, Thailand, Nepal, Argentina, Brazil and Kenya.

“The new data do suggest increases in both the number of injecting drug users and the prevalence of HIV in users,” Kamyar Arasteh and Don Des Jarlais of Beth Israel Medical Center in New York City wrote in a commentary on the study published in The Lancet.

According to the Reuters article, the researchers estimated that in 2007, nearly 16 million people around the world used injection drugs recreationally, the largest numbers of which were located in China, the United States and Russia.