My son Sam was diagnosed with Chronic Fatigue Syndrome 3 years ago after getting chickenpox. He went from being a healthy, sporty, young boy to someone who struggles with basic activities. 

Sam wrote a few words a couple of years ago to help his friends understand and they are still very relevant unfortunately:

https://samhayesweb.wordpress.com

CFS/ ME is more prevalent than MS or Hiv/AIDS but has little research or understanding. Sam's consultants can offer no medical prescriptions to help him- we are simply managing / resting / waiting for him to get better. 

Invest in ME Research is an independent UK charity finding, funding and facilitating a strategy of biomedical research into Myalgic Encephalomyelitis (ME or ME/CFS).The charity is run by volunteers - patients or parents of children with ME - with no paid staff.Overheads are kept to a minimum and all funds raised to go to promoting education of, and funding for biomedical research into, ME.Our efforts are focused on setting up a UK Centre of Excellence for ME which will provide proper examinations, diagnosis and in time treatment(s)/cure(s).