The emotional battle over HPV vaccination in Alberta has flared up again, after Calgary’s Catholic school board directed parents to a letter from Church leaders that warns the shots could encourage pre-marital sex.

The bishops’ letter says that abstinence outside of marriage is not only the right choice spiritually but the best protection against disease. Providing the HPV vaccine at school “sends a message that early sexual intercourse is allowed, as long as one uses ‘protection,’ ” the bishops assert.

As well as raising the promiscuity issue, the letter suggests the public-health community is divided on the vaccine’s benefits, a statement one leading scientist said was “hogwash.”

“We’re going to have to go back to square one and start the fight all over again,” said Eduardo Franco, a McGill University cancer epidemiologist and one of the world’s top experts on links between the human papillomavirus and cancer. “Too bad.”

Read the complete story at the National Post.