1. HIV INFECTION @ Human immunodeficiency Virus @ Enveloped, icosahedral, single stranded linear, RNA virus @ It belongs to the Retrovirus family that is classified into 2 groups: # Oncovirus group: containing Human T- cell Lymphocytic viruses, causing leukaemia and lymphoma # Lentivirus group: containing human immunodeficiency viruses 1&2

3. Routes of transmission of HIV: @ Sexual transmission @ From mother to baby. @ Blood transfusion @ Sharing of needles among drug addicts @ Bloody urine. @ No transmission by insects, saliva, tears, sweat, or faeces,

5. Clinical Picture: @ Stage I: Acute infection: fever, night sweats, malaise, diarrhoea. @ Stage II: No symptoms, for 1-10 years @ Stage III: Lymphadenopathy on all body @ Stage IV: AIDS symptoms & signs: Fever, diarrhoea, meningitis, candidiasis TB, lymphoma, pneumonia, septicaemia

7. Laboratory Diagnosis: @ Antibodies positive after 3 months (window period). @ ELISA to detect HIV antibodies @ Western blot to confirm ELISA tests @ PCR assays for both HIV RNA and DNA. @ Rapid oral HIV test, confirmed by ELISA @ HIV culture

9. Follow-up Investigations: @ By counting CD4 lymphocytes, using CD4 Counting Machine # Declining numbers of CD4 lymphocytes is a poor prognosis. @ ELISA to detect HIV p24 antigen. * Its presence is a poor prognosis