The Usher scandal -- that he allegedly has herpes and had sexual contact with individuals without telling them -- is about to get bigger, because 2 women and a man are going to file a lawsuit claiming Usher exposed them to the STD.

Celebrity attorney Lisa Bloom says she'll file the suit Monday in California and hold a news conference in NYC to correspond with the filing. One of the women will appear at the news conference. The 2 others will remain anonymous and will appear in the lawsuits only as Jane Doe and John Doe.

Bloom says all 3 individuals claim to have had sexual contact with Usher after 2012, and he failed to warn them he allegedly had an STD.