Teenage depression in the Illawarra has reached worrying levels, with up to one in five adolescents afflicted by the mood disorder, the Black Dog Institute says.The disturbing statistic equates to around five people in each school classroom living under the veil of depression.Michael Sluis, the Black Dog Institute’s community programs manager, said the prevalence was highest among those aged 18-24, highlighting the need for early detection and treatment. He said suicide was the third most common cause of death among young people in Australia. ‘‘The fact is that 70 per cent of mental health issues in adults first appear in adolescence,’’ he said. ‘‘If we can diagnose and treat people in adolescence, it’s possible for them to better learn how to effectively manage depression into adulthood.’’Mr Sluis said many young people struggled under the weight of peer pressure and family expectations. ‘‘Young people are at a time in their life when they are particularly vulnerable ... they are having to face the daunting task of looking for a career, getting out into tertiary education, taking responsibility for their lives, discovering the opposite sex - if you add a mood disorder to all of that, life can seem very overwhelming,’’ he said.‘‘Young people have to deal with technology, keeping up with the latest iPod and iPhone, and even bullying has changed now.‘‘Before, the home was a sanctuary where you could escape bullying; now it reaches into the home through the computer.’’Although depression has become a more acceptable social talking point, ARAFMI Illawarra service manager Kelly Parrish said there was still a strong stigma attached to the often-crippling condition.‘‘What we need to do as a society is encourage young people to talk, whether it be to a family member, a friend, a counsellor or a trusted teacher,’’ she said.Mr Sluis said depression did not have to be a life sentence.The institute will be holding a seminar for parents, teenagers and those who work with young people on Wednesday, February 23, at the Illawarra Performing Arts Centre. For more information call 93828203. For more advice on teenage depression, contact Headspace Illawarra on 42207660.Lifeline: 13 11 14.