Netherlands Cohort Study on Acute HIV Infection

Inclusion Criteria: * Written informed consent to store samples and perform genetic testing. * Separate written informed consent for invasive sampling procedures: leukapheresis, sigmoidoscopy with biopsies, lymph node excision biopsy and lumbar puncture, with storage of samples. * Age \>= 18 years * An acute HIV-1 infection, defined according to the Fiebig stages I-IV (acute infection), as described in the previous paragraph (HIV-1 RNA positive and 4th generation ELISA negative or HIV-1 RNA positive and 4th generation HIV ELISA positive with indeterminate Western Blot). Patients in Fiebig stage V and VI (recent infection) will only be included if they have a documented negative HIV test 6 months prior to the positive test or if they are in Fiebig stage V with a p31 negative blot * Female subjects should be willing to use adequate contraception. Exclusion Criteria: * Contraindication for proposed cART regimen (e.g. impaired renal function). * Mental disorder that in the view of the investigator would interfere with adherence to the treatment or the study procedures, or the decision to participate in the study. * Immunosuppressive medication or other diseases associated with immunodeficiency.