Cuba becomes the first country in the world to eliminate mother-to-child transmission of the virus.
Cuba has become the first country to eliminate the transmission of HIV and syphilis from mother to baby, the World Health Organisation has announced.
The WHO's director general, Margaret Chan, said it was "one of the greatest public health achievements possible" and an important step towards an Aids-free generation.
Over the past five years, Caribbean countries have had increased access to antiretroviral drugs as part of a regional initiative to eliminate mother-to-child transmission.
HIV and syphilis testing for pregnant women and their partners, caesarean deliveries and substitution of breastfeeding have also contributed to the breaking of the infection chain, said the WHO.
Carissa Etienne, the director of the Pan American Health Organisation, which partnered with the WHO on the initiative, said: "Cuba's achievement today provides inspiration for other countries to advance towards elimination of mother-to-child transmission of HIV and syphilis."
It is estimated that each year 1.4 million women living with HIV become pregnant. Untreated, they have a 15-45% chance of transmitting the virus during pregnancy, labor or breastfeeding. The risk drops to just over 1% if the mother and baby are treated with antiretrovirals.
Globally, more than 35 million adults and children are living with HIV, but the infection rate has slowed significantly, with 2.1 million, becoming HIV positive in 2013, down from 2.9 million in 2005, according to UNAids data.
Scientists have said eradicating Aids is feasible if HIV prevention continues to grow, even if there is no cure. The reduction in infection rates in Cuba is seen as a major breakthrough in the campaign to rid the world of the virus.
The incidence of syphilis transmission is close behind with 1 million pregnant women worldwide infected. This can be eliminated with simple treatments such as penicillin during pregnancy.
In 2013, only two babies were born with HIV in Cuba, and only five born with congenital syphilis.
According to the WHO, the number of children born every year with HIV has almost halved since 2009, to 240,000 in 2013.