I Got Morganella Morganii In My Sperm. My Doctor Prescribed

I got morganella morganii in my sperm. My doctor prescribed me "Ceftrex"shots to fight it in a 3-day dosis. Anyway, the antibiotic for the shots is too expensive. I would appreciate you letting me know the consequences of this bacteria, how harmful or risky it is and wheater there's a cheaper way to fight it. Thanks!