Inclusion Criteria:  For mother: Mother/child couple whose mother is HIV-1 infected, whether or not the infection is known and treated at delivery Mother of full age 18 years or older Mother agreeing to be contacted by telephone to ensure that appointments are respected. Mother has signed the informed consent form to participate in the study (and agrees to be followed, along with her child, at the centre for the duration of the study).  For children:  Live newborn baby Free, informed and written consent must be signed by the holder(s) of parental authority and the investigator for the child's participation in this research (at the latest on the day of birth and before any intervention carried out on the newborn in the trial).  Exclusion Criteria:  For mother:  Mother infected with HIV-2  Not included due to monitoring difficulties:  Anticipated absence(s) that could hinder participation in research (travel abroad, relocation, travel); Insufficient motivation to be followed for 9 months in the centre. No mobile phone or refusal to be called by investigators if necessary. Mother and/or children already participating in another biomedical study  For children:  Not included for reasons of caution (child with severe congenital malformation or clinical symptomatology suggesting opportunistic infection). The child has a known allergy to the drug given as part of HIV prophylaxis in Guinea or to its components.