Mental health assessments carried out on 269 children living in or near the tower revealed 214 needed treatment. Some 146 of these are now receiving care, while 63 have completed their therapy.
A further 24 families of children referred to mental health services refused to allow them to be assessed, while 10 infants and adolescents failed to turn up for the tests, according to the data.
NHS psychologists said they expect the number of children known to be suffering with mental health problems due to the fire to grow.
So far, experts have been screening children referred by a teacher, counsellor or parent for trauma symptoms.
But from March they will try to identify children suffering severe psychological effects of the disaster by going into the three schools nearest Grenfell Tower and screening them directly.
“It’s like an outbreak of head lice in the area – if you see a few people coming into the pharmacy because of head lice, you think: maybe we should send a nit nurse into the school,” Dr Jai Adhyaru, who is leading the Grenfell Trauma Service for Children and Adolescents, told The Independent.
“We’re seeing a steady referral flow and we want to see if it’s better to go into the school and check for ourselves.”
She said it was “difficult to know” how many children needed help processing the traumatic events of 14 June 2017. Experts at the Central and North West London NHS Foundation Trust have estimated up to 10,000 people have been psychologically affected by the fire, which killed 71 people.
Alongside screening – which involves a questionnaire designed to detect symptoms of trauma – secondary school pupils will have health and wellbeing lessons where they will learn about the symptoms of PTSD.
The parents of primary school children, meanwhile, will be invited to coffee mornings aimed at reducing stigma around mental health.
“The thought of your child talking to a stranger about God knows what can be threatening because there’s a degree of mistrust in the community about formal agencies – it’s understandable in these circumstances,” Dr Adhyaru said.
She added the pilot would only start in the three schools closest to Grenfell Tower because they suffered the most disruption after the blaze.
But, if the team had more resources, it would roll out the scheme across the borough and into neighbouring areas, she said, since students at schools several miles away saw the building engulfed in flames and knew people who died in the blaze.
She said if children complained regularly about stomach aches or headaches, had trouble sleeping or wanted to sleep excessively, it could be a sign they were traumatised.
“Children have described how their tummy starts to hurt when they think about [the fire], so they try not to think about it,” she said.
“Trying not to think about something is not helpful because it will keep popping back.”
Dr Adhyaru said she had also assessed a number of infants who had suddenly reverted into earlier stages of childhood after the fire.
“In the little ones we see what we call regressive behaviour, children moving back into an earlier developmental stage: thumb-sucking, bed-wetting, or [they are] clingy and don’t want to leave their parents,” she said.
“It can slow their developmental progress if they stay stuck in one of those regressive states, which can then cause distress.”
Meanwhile, older children tend to have smells or images pop into their heads. “Quite a few teenagers have told me they feel like they’re going mad,” she said.
Children were being psychologically affected by seeing their parents and other adults around them experience distress.
The symptoms were also being exacerbated by instability in their living arrangements, she said. Eight months on from the deadly fire, only 60 out of 209 households have moved into permanent accommodation, although 175 have now accepted the offer of a new home.
“If people don’t know where they’re living or children don’t know which schools they’re going to it can be quite anxiety provoking,” she said.
Their trauma was compounded by seeing adults around them in distress, she said.
“They’ve also seen adults in a way that perhaps isn’t part of the normal childhood experience. Children see adults as a different type of person. So it’s very unsettling when they see their teachers, their parents and their neighbours impacted on.
“The NHS response has been to obviously screen children, but we can’t do that without checking in on how their parents and carers are doing as well.”
Mental health teams have now contacted 5,300 adults through outreach work, which largely involves door-knocking. More than 1,200 have been referred for treatment, 797 of whom have had their first session.
Access to social media was also compounding the trauma children suffered, she said.
“I don’t have the stomach to listen to a phone call made by someone inside the tower in their last moments of life. I don’t really want to see the footage. But kids are curious and they’re on social media. So they’re exposed to this imagery. It is unprecedented to have so much footage. It’s really raw and of course that’s going to play on their minds.
“That’s been an additional component in that disaster – that there’s so much material out there.”
Elizabeth Campbell, leader of Kensington and Chelsea Council, said: “It is hugely important that we spot the early warning signs in our children and make sure they have the help that they need.
“Many people will have a degree of trauma after the Grenfell Tower tragedy, and it is important that they recognise it and seek assistance.”