* Use by heterosexuals and transsexuals also justified
* Clarification needed because of translation error in book
* Theologian calls words "groundbreaking", liberals happy
* AIDS prevention groups applaud move (Recasts, adds Global AIDS alliance comment, paras 10-11)
By Philip Pullella
VATICAN CITY, Nov 23 (Reuters) - Pope Benedict's landmark acknowledgement that condoms are sometimes morally justifiable to stop AIDS can apply to anyone -- gays, heterosexuals and transsexuals -- if that is the only option to avoid transmitting the HIV virus to others, the Vatican said on Tuesday.
The clarification, which some moral theologians called "groundbreaking", was the latest step in what is already seen as a significant shift in Catholic Church policy.
It came at a news conference to launch the pope's new book, "Light of the World: The Pope, the Church, and the Sign of the Times".
In the book, a long interview with German Catholic journalist Peter Seewald, the pope made clear he was not changing the Catholic ban on contraception, but, using the example of a male prostitute, said there were cases where using a condom to avoid transmitting the HIV virus could be justified.
Vatican spokesman Father Federico Lombardi made the clarification because the German, English and French versions of the book used the male article when referring to a prostitute, but the Italian version used the female form.
"I asked the pope personally if there was a serious distinction in the choice of male instead of female and he said 'No'," Lombardi said.
"The point is it (condom use) should be a first step towards responsibility in being aware of the risk of the life of the other person one has relations with," he said.
"If it is a man, a woman or a transsexual who does it, we are always at the same point, which is the first step in responsibly avoiding passing on a grave risk to the other."
Theologians, AIDS activists and liberal Catholics said the latest developments marked a highly significant, perhaps even historic, change in the Church's attitude to condoms.
POTENTIAL TO SAVE LIVES
"The pope's statement ... is a startling and welcome shift by the Vatican that has the potential to save tens of thousands of lives," said Dr. Paul Zeitz, executive director of the Washington-based Global AIDS Alliance (GAA).
"The pope has created the possibility of rapid change in the way the Catholic Church views HIV/AIDS and how it can preserve the sanctity of human life," Zeitz said.
Lombardi appeared to take the debate beyond the confines of prostitution in the context of fighting the transmission of AIDS, although the church prefers measures such as abstinence.
"The fact that an official Vatican spokesperson seems to be extending the possibility of use clearly is groundbreaking," said Rev. John T. Pawlikowski, a professor of social ethics at the Catholic Theological Union in Chicago.
"The real question is whether this papal statement will impact pastoral activity on the ground, particularly in AIDS-affected regions of the world," he told Reuters.
The church had been saying for decades that condoms were not even part of the solution to fighting AIDS, even though no formal policy on this existed in a Vatican document.
The late Cardinal John O'Connor of New York famously branded the use of condoms to stop the spread of AIDS as "The Big Lie".
"The Vatican's acknowledgement that Pope Benedict's acceptance of condom use to prevent the spread of sexually transmitted infections relates to everybody shows how significant the pope's comments are," said Jon O'Brien, president of the U.S.-based Catholics for Choice group.
In the book, the pope says the use of condoms could be seen as "a first step towards moralisation", even though condoms are "not really the way to deal with the evil of HIV infection".
Through the book and Lombardi's comments, the pope seemed to be giving a cautious, qualified endorsement of the "ABC principle" (Abstinence-Be faithful-Condom) espoused by many governments and health organisations in preventing AIDS.
Archbishop Rino Fisichella, a Vatican official who presented the book, said Catholics had to "respect" the pope's words even though they were not made in an official papal pronouncement.
"For the first time, the use of condoms in special circumstances was endorsed by the Vatican, and this is good news and a good beginning for us," said Margaret Chan, director-general of the World Health Organisation. (Additional reporting by Tom Heneghan in Paris and Kate Kelland in London; Editing by Kevin Liffey and Louise Ireland)
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