As others across this site say, cleanse the Colon, Kidneys and Liver.
This 1st link is to Dr Mercola Interviewing Dr. Natasha Campbell-McBride. She has a son who suffered from Autism and came up with a great way to rebuild his Immune System to help his autism. She also wrote a book “Gut and Psychology Syndrome”. This book is great information for rebuilding the immune system.
I have no idea on water sources in Egypt, but here in America anyone living with municipally treated water is slowly killing off their immune system. The Chlorine added to the water is lethal to our friendly bacteria. Depending on who you read, 75 to 85% of our immune system is in our GUT, our intestinal tract. So a filter to rid the water of the chlorine is necessary as well. Even just a shower filter would be helpful.
Read Jon Barrons "Lessons from the Miracle Doctors", Chapter 11, "Dying of Thirst", Page 87 "Chlorine" (PDF download).