Yes, BILHARZIAS is a Scrabble word!

Letter values in Scrabble US: B 3, I 1, L 1, H 4, A 1, R 1, Z 10, I 1, A 1, S 1.

Is it a valid word?

BILHARZIAS is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

an infestation with or a resulting infection caused by a parasite of the genus Schistosoma; common in the tropics and Far East; symptoms depend on the part of the body infected