With the moon shining brightly, it could almost be daytime. If it wasn’t for the eery silence on the streets and the chill in the night air.

Night is the time when David goes outside to play. While other children sleep in their beds, David swings on the ropes of a playground construction under the full moon.

David suffers from XP, also know as the moon illness. The sun is his enemy, its light makes him ill.

Xeroderma Pigmentosum, XP, is a rare disorder which causes extreme sensitivity to the sun’s ultraviolet rays. Unless XP patients are protected from sunlight, their skin and eyes can become severely damaged, leading to cancers of the skin and eye.

There is no cure for XP. Children and adults with the disease can only protect themselves from the deadly rays of the sun using sunblockers with at least factor 60 or clothing, hats and sunscreens.

Around 5,000 children in Germany are said to be ill due to uncurable genetic disorders, including XP.

Factor 60 sun cream

The battle with sunlight begins in the morning. Nurse Regina comes every day to see to David and rub in the ointment which is essential to survival.

In David’s classroom, a plastic film has been stuck on the windows, in order to keep out the harmful ultra-violet rays. This way David's class doesn't need to have the curtains drawn.

"The worst thing is that children of the moon are always getting tumours, and these have to be operated on every time," David says.

There is a new tumour on David’s upper lip. This will be David's 16th operation. Regular trips to the dermatologist is part of his daily life, as early recognition of cancerous growths can be life-saving.

Disease is incurable

As XP is uncurable, treating the disease in the sense of treating the cause is virtually impossible. Doctors' hopes lie in gene therapy, but at current, only preventive measures can be taken.

David has now been given a protective helmet, which should make David's life easier, and maybe even prolong it.

According to his mother, David’s life expectacy was not long – he was thought to live until the age of 10. However, David has already reached the age of ten. "So I say to myself, if he makes it to 15, he won't die," his mother told Deutsche Welle.

His new helmet protects him from his old enemy, the sun. For the first time, David can go outside into the school yard for break.

But otherwise, the 10-year-old will have to stick to his usual routine.

In spite of all the precautions, night time is still the best for David, who knows his way around in the dark. But soon winter will be over, and the days will grow longer - unfortunately.