Cuba became the world’s first country on Tuesday to win World Health Organization certification that it had eliminated mother-to-child transmission of both H.I.V. and syphilis. Despite its poverty, Cuba provides basic health care to all citizens. Since the 1980s it has successfully suppressed its H.I.V. epidemic, initially through forced quarantine and, since 1993, by widespread testing and treatment.

It was congratulated on Tuesday by the heads of the W.H.O. and Unaids, the United Nations AIDS-fighting agency.

However, the W.H.O. allows countries that achieve only 95 percent of elimination targets to be certified; in 2013, five Cuban babies were born with H.I.V. or syphilis. Cuba was the first country to request the certification, according to a spokeswoman for the Pan American Health Organization, the W.H.O.’s Western Hemisphere branch.

More than 20 others have since asked, she added, and those next in line are Bulgaria, Moldova, Turkmenistan and Thailand.