In Spain, the incidence of HIV in adolescence is low, representing 11.5% of cases. We present the case of a 15-year-old teenager  from Cuba, highlighting the aspects in which Primary Care is fundamental.Introduction:  In Spain, the incidence of HIV in adolescence is low, representing 11.5% of cases. We present the case of a 15-year-old teenager  from Cuba, highlighting the various aspects in which Primary Care is fundamental. Case Clinic: 14-year-old teenager , with a primary  infection of syphilis,  who  moved from Cuba to Marbella . He came to the Family Doctor consult  to continue medical follow-up. In Cuba, he presented an inguinal lesion suspected of syphilis that was confirmed with serology and treated with  a single dose of benzatinic Penicillin G (2.4 million units im). After  the window period of  STIs , he  did a new serology test: HSV-1, HSV-2, Syphilis and VIH. The tests showed a positive Ig M for  HSV-2 , AC against HIV,  and Ig G against syphilis. As  a under-age , the results were  communicated to his mother and later to him.  He  was referred to the Internal Medicine Infectious Group of the Costa del Sol Hospital, the  reference University Hospital in the area, where he was treated with Antiretroviral Therapy  (HAART)This case is unusual, given that the incidence of HIV in Spain is low, and even more so, a case in adolescenceIn this clinical case, we can show  why  Primary Care is fundamental: Care for the immigrant patient; health education, specifically , STIs , including VIH prevention, sexual education, and mental health.  Professionals as family doctors, nurses are  responsible for carrying out these tasks.Health education activities include workshops (nutrition, stress management, first aid), talks (addiction prevention, sexual health, mental health, ), and others such as seminars, support groups, focusing on promotion, prevention, and healthy lifestyles for teenagers  with the program Forma Joven.We must learn that STI prevention activities and social support must be thorough and constant to educate the population and prevent new infections as much as possible.