The situation is so serious that his team did not send children home for Christmas, as they normally do. Isolation has also disrupted the usual teenage transition as young people shifted from belonging to their family to belonging to their peers, added Dr. Vermeiren added. "You feel empty, lonely and this loneliness drives you into despair," he said.
In Italy, calls to the main hotline for young people who have thought about or tried to harm themselves have doubled over the past year. The beds in a children's neuropsychiatry department at the Bambino Gesù Children's Hospital in Rome have been full since October, said Dr. Stefano Vicari, the director of the department.
The hospital stays of young Italians who have injured themselves or attempted suicide increased by 30 percent in the second wave of falls, he added.
"For those who say that after all these are challenges that young people must go through in order to get out stronger, it only applies to some who have more resources," said Dr. Vicari.
Catherine Seymour, director of research at the Mental Health Foundation, a UK-based charity, said young people living in poorer households are more likely to experience anxiety and depression among nearly 2,400 teenagers, according to a study.
"People in poorer households may be more likely to lack space and internet access to help with schoolwork and communicating with their friends," said Ms. Seymour. "They can also be affected by their parents' financial worries and stress."
Studies from the first locks suggest they may have already left indelible marks.
In France, a survey of nearly 70,000 college students found that 10 percent had suicidal thoughts in the first few months of the pandemic and more than a quarter suffered from depression.