Pure selfishness.
Just like the people who knowingly spread HIV.
They feel that if they’re going down, they’ll take others with them.
Her antics were in exactly the same vein.
According to her alma mater, University of Texas, Arlington she pursued a two-year postgraduate fellowship in applied epidemiology with the Centers for Disease Control and Prevention in Las Vegas after she was rejected by Doctors Without Borders. (Later accepted for DWB)