After a five-day trip to Portugal, which recently came to terms with its own clerical sex abuse crisis, Pope Francis said the Catholic Church must abandon its practice of covering up abuse and instead be "very open" about how it is confronting the crime.

During a news conference on the pope's return flight to Rome from Lisbon, Portugal, Aug. 6, the pope said bishops who have not adopted a "zero tolerance" policy toward abuse need to "take charge of that irresponsibility."

Pope Francis had met privately with abuse survivors for more than an hour Aug. 2 during his stay in Lisbon for World Youth Day; he told reporters they "dialogued about this plague" of abuse.

"The church used to follow the conduct that is followed in families and neighborhoods: it covers up," he said, adding that addressing abuse must take in those places, too.

Speaking directly with abuse survivors, as he has done on several of his international trips, is "good for me, not because I like to listen to it but because it helps me take charge of that tragedy," he said.

In the church, he said, "I urge that we be very open" about matters of abuse.

Speaking about abuse more generally, Pope Francis called child pornography "one of the gravest plagues in the whole world," noting how it has become easily accessible on any cell phone.

"This comes into our homes. Sexual abuse with minors is filmed live. Where is it filmed? Who is responsible?" the pope asked. "I want to stress this, because we don't realize that things are so radical."

He also identified other types of abuse that need to be addressed in the world, such as child labor and the ongoing practice of female genital mutilation.

After a taxing five days in Portugal with packed daily schedules, the pope said that he is in good health and is recovering normally from the abdominal surgery he underwent in June to treat a hernia, mentioning that his stitches had been removed and that he is wearing a band "for two to three months" until the muscles in his abdomen get stronger.

He also talked about his trip to Marseille, France, Sept. 22-23, explaining that it is meant to be a meeting of bishops and politicians "to seriously reflect on the problem of migrants."

"The Mediterranean is a cemetery, but it's not the largest cemetery; the largest cemetery is North Africa," he said after discussing the migrant detention centers in the region, which he referred to as "lagers," a term for concentration camps.

Pope Francis also responded to questions about his eyesight that arose during his trip to Portugal after he said he didn't want to strain his vision during an event Aug. 4 and proceeded to largely put aside his prepared texts and deliver improvised remarks at his events. He told reporters a light was shining directly in his eyes at the Aug. 4 meeting and that he spoke off-script at most of his World Youth Day events because "young people do not have a long attention span."

He explained that he cut short his homily, delivered to 1.5 million people in Lisbon's Tejo Park Aug. 6, because "homilies, sometimes, are a torture; they talk -- blah, blah, blah."

"The church must convert itself in this aspect of the homilies," he said, and learn to be "brief, clear, with a clear, affectionate message."

Discussing World Youth Day, the pope answered a question about his repeated message to young people that the church is for "everyone, everyone, everyone." A journalist asked what he meant by that when the church does not allow women and gay people to receive "all the sacraments," referring to ordination for women and marriage for gay couples.

"If someone is inside the church and can't receive a sacrament, this does not mean (the church) is closed," he said. "Each person finds God by their own path inside the church, and the church is mother and guides each one by their own road."

The pope also shared that during World Youth Day he spoke with a young person who told him he had previously considered suicide.

There are "so many young people who are anxious, depressed," Pope Francis noted, but "the media doesn't say anything because the media is not informed."

He said that in some countries where universities are very demanding, "young people who aren't able to earn a degree or get a job commit suicide because they feel a great shame.

"I'm not saying it's an everyday thing, but it's a problem," he said.