It is essential that you contact anyone you may have infected as quickly as possible in order to let them know. This applies to people you met and were in close contact with up to 48 hours prior to developing your first symptoms.
Close contact means any person who you met with for at total of at least 15 minutes, with a distance of less than two metres between you over the course of a day, including outdoors. Anybody who lives in the same household as you will always be counted as a close contact.
You will also be telephoned by a contact tracer within 48 hours of receiving your positive test results.