Pope Francis Says Contraception May Be 'Lesser of Two Evils' During Zika Virus Outbreak Pope Francis commented on the Zika virus outbreak during his trip to Mexico.

 -- With the mosquito-borne Zika virus continuing to spread through Central and South America, Pope Francis said today that contraception could be seen as "the lesser of two evils" if women are concerned about having children with the birth defect microcephaly.

The Zika virus is usually mild, but has been associated with a rise of the alarming birth defect, characterized by an abnormally small head and brain, often leading to significant developmental delays.

The pope compared the situation to a decree issued by Pope Paul VI, which said nuns in Africa could use contraception due to the threat of rape.

"Avoiding pregnancy is not an absolute evil," Francis said. "In certain cases, as in this one, such as the one I mentioned of Blessed Paul VI, it was clear. I would also ask doctors to do their utmost to find vaccines against these mosquitoes that carry this disease. This needs to be worked on."

Francis did say in strong terms that abortion is "an absolute evil" and should not be considered even if there is a risk the infant will be born with microcephaly.

The World Health Organization issued new guidelines today to guard against the sexual transmission of the Zika virus. The organization advised men and women returning from areas where the transmission of the virus is ongoing to adopt safer sex practices or consider abstinence for at least four weeks. Partners of pregnant women should adopt safer sex practices, including barrier contraception or practice abstinence for the duration of the pregnancy, the WHO recommended.

The virus is most commonly spread from mosquitoes to humans, but it has been documented to spread through sexual contact and blood transfusions.