Post-exposure prophylaxis (PEP) refers to preventive medical measures taken when a person has had contact with a pathogen. This is intended to prevent the outbreak of the disease or to mitigate its course.
The patients are either treated with medication or vaccinated. In some cases an active and a passive vaccination can be given. While the active vaccination stimulates the immune system to produce antibodies and the protection is delayed, the passive vaccination gives the patient for example antibodies from a person who has already recovered, which should protect faster. Post-exposure prophylaxis is used for diseases with a high risk to the patient, such as rubella in pregnancy, HIV or rabies. Scientists are currently working on antibodies for post-exposure prophylaxis against COVID-19.