Mycoplasma Genitalium

A new STD has been discovered -- Mycoplasma Genitalium -- the predecessor to pelvic inflammatory disease. Researchers at University College London examined urine samples of about 4,500 men and women (ages 18-44) and found that 72 people who were sexually active with at least one partner tested positive with MG, while those who have never been sexually active's results all came back negative. It is hard to catch MG, because it often doesn't show symptoms; 50-90% of people diagnosed with the STD didn't report any symptoms. For those that do have symptoms, painful urination and bleeding after sex are common for women, and watery discharge is normal for men. MG is treatable with the antibiotic azithromycin, AKA a "z-pack." 

http://www.cnn.com/2015/12/07/health/what-to-know-std-mg/index.html