If a blind person owns a dog that he constantly touches, does he have to wash his hands every time before he makes a Bracha?

From Talmud (Nazir 48a and Rambam – H. Tumas Ochlim 15: 9) is obvious that one who is prohibited to become Tameh, as a Cohen or a Nazir are, may touch animals that are not Kosher. However, Shulchan Oruch Horav (90: 3) debates if one should wash his hands before reciting a blessing or Tefila. Yafeh Lalev (1: 24) insists that he has to, while Kaf Hachaim (4: 81) rules that when possible he should. The blind should indeed be careful that on those times he should was his hands with a small portable plastic cleaning fluid dispenser.