A debilitating chronic illness that affects 20,000 New Zealanders is likely to be causing large numbers of school absenteeism in teenagers.
Wellington psychologist Rose Silvester, whose son has long-standing Myalgic Encephalomyelitis/Chronic Fatigue Syndrome, said the complex disease severely impacts the development of academic, cognitive and social skills in young people. It has no cure.
There is currently no data on New Zealand students with ME/CFS but a new study in Australia shows students with ME/CFS missed an average of 40 per cent of classes over a term, or at least two days per week.
Their healthy peers by comparison, missed less than half a day per week.
"Sadly this is likely to be a significant underestimation as this study excluded students with severe cognitive impairment - a core symptom of ME/CFS and the reason that many children are not able to attend school or participate in any meaningful education years," Silvester said.
The study also excluded students who were permanently absent from school or home schooled.
"Many children with ME/CFS cannot attend school at all, and parents are having to leave paid employment to educate their child through the health school system."
Silvester said concerns over loss of education was one of the challenges regularly discussed by the 75 families of children with ME/CFS who had joined the Facebook support network NZcare4ME .
The others included misdiagnosis, misinformation and a lack of medical support.
ME/CFS is a chronic stigmatised disease that simultaneously affects multiple systems in the body, with post-exertional malaise a key ailment.
ME/CFS patient advocate Sam Featherstone, who created the 20,000 missing website with Silvester, said up to 80 per cent of those affected by ME/CFS in New Zealand were women and children.
"But the New Zealand health system has no meaningful clinical pathway for supporting people with ME/CFS," she said.
"Clinical pathways are key to identifying health status, options for treatment, and the provision of appropriate care, rehabilitation and recovery services."
Featherstone and Silvester created a visibility campaign in May - when ME advocates globally campaign to raise awareness and money for research through the #MillionsMissing effort.
"The aim is to reinforce the biological basis for the disease and to mitigate against the historical mischaracterisation of ME/CFS as hysteria, and persistent belief that it is a functional neurological, psychosomatic and a psychological illness," Featherstone said.
Silvester said the education concerns in particular had been a "source of continual distress among the parents of our group".
"Particularly with kids being required to return to school or finding the health school is unable to meet their needs in some areas in New Zealand. This has resulted in awful 'crashes' for some kids."
ME sufferers who exert too much energy spiral into what is known as a "crash", with an exacerbation of symptoms for days, and sometimes months and years.
"It really is a huge and perplexing problem that such a large group of people who are so unwell have been forgotten and left to fight and advocate for themselves."
The Ministry of Education deputy secretary sector enablement and support, Katrina Casey, said schools did not provide attendance data based on particular illnesses.
"Students with health conditions that have resulted in persistent absences from school can seek the support of the Regional Health Schools."
Regional Health Schools provide schooling, either in hospital or at home, for children who have a medical certificate proving they cannot attend school.
Northern Health School principal Richard Winder said of the 932 students enrolled at his school, which covers 60 per cent of the population, 48 listed ME/CFS as the reason.
"There's probably another group of young people whose presenting symptoms are maybe not that bad to meet the threshold for somebody to say they're too sick to go to school, and they're having odd days off."
Winder said ME was looked down on by many, without medical qualifications, as "not a real thing" and it was not well supported.
"People are likely to look at you and think 'Oh there's nothing wrong with them really, they just need to harden up and go to school'. I'm sure that makes it very difficult for families and young people with that diagnosis."