After ending a dramatic tour of Mexico, Pope Francis on Thursday seemed to open the door for limited use of artificial contraception, long prohibited by the Roman Catholic Church, to prevent pregnancies at risk from the disastrous, fast-spreading Zika virus.
Speaking to reporters aboard his flight from Mexico's Ciudad Juarez to Rome, Francis was asked if a "lesser evil" — abortion or contraception — could be permitted to prevent the disease from harming a fetus. Researchers believe Zika may be linked to serious birth defects, such as debilitating under-formation of the brain, and hundreds of cases have been reported in Latin America.
Under no circumstances, Francis said, should abortion be considered a "lesser evil," and he said the procedure should be avoided at all cost. "It is a crime, [killing] one person to save another," he said. "That is something that the Mafia does ... an absolute evil."
However, preventing a pregnancy that was in danger of being exposed to Zika might be allowable, he said, but only if it would most certainly prevent a pregnancy at risk.
"Avoiding pregnancy is not an absolute evil," Francis said. He cited Pope Paul VI's decision in the early 1960s to allow religious women facing rape during upheaval in the Belgian Congo to use contraception.
However, in the milestone 1968 encyclical Humanae Vitae, Paul VI banned use of birth control under normal circumstances. The church teaches that procreation is one of the most important duties of married couples.
The Vatican has been criticized in the past for taking a hard line against the use of condoms to stop the spread of AIDS, especially in Africa and Asia. In most of Latin America, where Zika is most common, abortion is illegal and birth control can be hard to come by.
In all of Mexico and Central America, it is only in Mexico City, where the pope just visited, that abortion can be obtained on demand.
Some countries, such as Nicaragua, ban it in all cases, including rape, incest and the health of the pregnant woman or girl.
Latin American bishops have become more conservative in recent times, and it was unclear what they would say about what appears to be a new opening voiced by the pope.
What Francis said he really wanted to happen is for "doctors to do everything possible to find a vaccination for this disease."
The pope answered a wide range of questions at a rambling news conference, touching on Donald Trump and his plans to build a wall on the U.S. border with Mexico and on recent revelations that Pope John Paul II sustained a long, loving but apparently platonic relationship with a married woman.
On John Paul's friendship with American-Polish philosopher Anna-Teresa Tymieniecka, the pope was a supporter. "A man who does not know how to have a friendly rapport with a woman," he said, "is missing something," adding that he often consults women for their opinions.
Two Mexican reporters asked about what many in Mexico saw as glaring omissions in the pontiff's dozen or so prepared speeches: the 43 college students kidnapped and presumably killed by corrupt authorities, and the clergy sexual abuse scandal as represented by the late Mexican priest Marcial Maciel.
Maciel, a Mexican-born priest who founded the Legion of Christ, stepped down as head of the order after having been implicated in a broad array of sex abuse allegations involving boys and young men. It was also revealed that he had fathered up to six children before his death in 2008.
Francis took exception to the criticism. He noted he had repeatedly cited the plights of murdered and missing Mexicans and the corruption of government officials and business entrepreneurs in terrorizing and repressing the most downtrodden of society.
The families of the 43 had said they wanted a private meeting with the pope, and when that was not granted, some said they would not attend his Masses. Francis said there had been internal disputes among the many organizations representing Mexico's more than 25,000 missing people and that he thought the best solution was to invite all to the final Mass at the border Wednesday in Ciudad Juarez.
"Mexican society is victim of all of this, of crimes, of 'cleansing' people, of throwing them away," he said. "It is a very large pain that I carry with me, because these people do not deserve a drama like this."
On priest abuse, Francis had forceful words for bishops who simply transfer pederast priests from parish to parish, as has often been the case. "They should resign, clear?"
He said his predecessors, Popes John Paul II and Benedict XVI, had condemned abuse and moved to make reforms. Activists, however, say the church acted woefully late and that abuse and coverups continue today.
As for Maciel, who fathered children and lived the high life, the powerful, conservative congregation he created, the Legion of Christ, has been overhauled, the pope said.
He was pointed, though, in his condemnation of child sex abuse by clerics.
"It's a monstrosity," he said. "Because a priest is consecrated to bring a child to God. And if he consumes him in a diabolical sacrifice, it destroys him."
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