Combined cases of syphilis, gonorrhea and chlamydia reached an all-time high in the United States in 2018. However, many STDs are asymptomatic, which means they have no obvious symptoms.
Other STDs (HIV and syphilis) can be active inside your body before signs of the infection become apparent. Therefore, these statistics do not include the thousands of people who currently have an STD, but do not know it. For more: