[Is it a sexually transmitted disease?]

STD-associated questions and symptoms are submitted frequently to general practitioners and STD outpatient-clinics. In this teaching article we address several important clinical questions regarding epidemiology, risk assessment, testing policy, diagnostics and prevention. STD's form a separate category of infectious diseases because of the role of sexuality. Good communication about sexual behavior is indispensable for an adequate diagnosis. We discuss the recognition of extragenital manifestations of STD, which requires alertness. Estimating the STD-risk based on sexual behaviour is essential for testing policy. Persons at high risk are tested for gonorrhoea, syphilis, hiv and hepatitis B. In other cases testing is based on symptoms and complaints. HIV and syphilis are serious std's. Early detection followed by treatment is important in preventing health damage and preventing further spread. Hiv-indicator-conditions are useful alarm-signs for this purpose. PrEP can help not to acquire hiv and increases sexual health. It can be prescribed by gp's and public health clinicians. But condom-use remains crucial in prevention.