JOHANNESBURG, Dec 1 (Reuters) - South Africa, that has one of the world's worst AIDS epidemics, has made headway in fighting the HIV virus, but condom use is still insufficient, government leaders said on Saturday.

One in nine South Africans are infected with HIV, but President Thabo Mbeki's government has been criticised for not doing enough to halt the spread of the disease despite the heavy economic and human toll.

Health Minister Manto Tshabalala-Msimang cited a study showing a decline in HIV among pregnant women -- a benchmark used to measure infection amongst the broader population.

"The report of the 2006 antenatal survey results released this year showed a decrease in the prevalence of HIV amongst pregnant women who use public health facilities," she was quoted as saying by news agency SAPA.

"It is down to 29.1 percent in 2006 compared to 30.2 percent in 2005 ... The decline in the under 20s from 15.9 percent in 2005 to 13.7 percent in 2006, in particular suggests a possible reduction in new infections in the population," she said at an event to mark World AIDS day in the northern Limpopo province.

Mbeki, who has been criticised for not taking the lead in the charge against AIDS, called on South Africans to use condoms.

"What is really of importance is that we must, all of us, take these messages very seriously, particularly our young people," Mbeki said on SABC public radio.

"We don't want our people to be suffering from ill health when they could have handled their own lives in a way that makes for healthy lives." (Reporting by Gershwin Wanneburg; Editing by Richard Balmforth)

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