Yes, AIDS is a Scrabble word!

Letter values in Scrabble US: A 1, I 1, D 2, S 1.

Is it a valid word?

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

a serious (often fatal) disease of the immune system transmitted through blood products especially by sexual contact or contaminated needles
a resource
the activity of contributing to the fulfillment of a need or furtherance of an effort or purpose
money to support a worthy person or cause
the work of providing treatment for or attending to someone or something

Also: acquired immune deficiency syndrome, economic aid, financial aid.