Medical experts are sounding the alarm about a silent epidemic of cancer in men, head and neck cancer called by the human papillomavirus, or HPV. A new study indicates that HPV-related cancers have surged, with 11.5 percent of men in the U.S. infected with oral HPV between 2011 and 2014, compared to 3 percent of women.

The study, published in the Annals of the Internal Medicine, finds that people with more sex partners are more likely to contract HPV, a sexually transmitted disease. You’re also more likely to have it if you smoke, especially marijauna, researchers found. You’re also more likely to have it if you’re black.

While most people don’t even notice the infections and get over them after a while, since HPV doesn’t cause any symptoms at first, sometimes the infected tissue has DNA damage that can result in the growth of malignant tumors. A total of 39,000 people were diagnosed with a cancer caused by HPV every year based on statistics between 2008 and 2012, which breaks down to 59 percent of them for women and 41 percent for men.

“Genital human papillomavirus (also called HPV) is the most common sexually transmitted infection in the United States,” reads a CDC statement. “Most types of HPV are not harmful to people. Most people who become infected with HPV do not know that they are infected. More than 40 types of HPV can infect the genital areas. Some types are known as cancer-causing types. HPV 16 and 18 are the two most common cancer-causing types. In the United States, HPV type 16 causes about half of cervical cancers, and types 16 and 18 together account for about 70% of cervical cancers. Infection with a cancer-causing HPV type is considered necessary to get cervical cancer, but the vast majority of people with an HPV infection do not get cancer.”