Hi , thanks for writing here. Both chicken pox and shingles are caused by same virus. Chicken pox once occurred give life long immunity.But virus remains dormnant in nerve roots for many years.In adult life this may lead to shingles or herpes zoster. Since you have splenctomy done ,you have somewhat low immunity and there is a fair chance you may get shingles. Avoid direct contact with your son.You can just wear mask to prevent transmission of virus from him. Eat healthy food and fresh fruits rich in vitamin c which will increase your immunity.You can also take some multivitamin tablets for few days. Consult your doctor if you have any burning sensation and get treated accordingly. I hope this can solve your query.Take care.