Last reviewed: 27 Dec 2021
Last updated: 31 May 2018



History and exam

Key diagnostic factors

  • exposure to HIV within past 72 hours
  • breakage, slippage, or nonusage of a condom
  • history of ejaculation from source
  • trauma or skin break
  • genital ulcers
  • source from high-risk group for HIV infection
  • source from geographic area with high HIV prevalence
  • high-risk sexual history in exposed person
  • detectable HIV viral load in source

Other diagnostic factors

  • history of negative HIV test in source
  • source with hepatitis co-infection
  • antiviral HIV resistance in source
  • current prescription or nonprescription medications
  • history of drug allergies
  • flu-like illness

Risk factors

  • blood transfusion from HIV-positive donor
  • sharing injecting equipment
  • needlestick injury
  • receptive anal intercourse
  • receptive vaginal intercourse
  • mucus membrane exposure
  • insertive anal intercourse
  • insertive vaginal intercourse
  • receptive oral sex (fellatio)

Diagnostic investigations

1st investigations to order

  • HIV antigen/antibody blood test
  • rapid point of care (POCT) HIV test
  • renal function tests
  • serum aspartate aminotransferase or alanine aminotransferase
  • hepatitis B serology
  • hepatitis C serology
  • syphilis serology
  • pregnancy test

Investigations to consider

  • HIV viral load if symptoms of HIV seroconversion

Treatment algorithm



Ming Jie Lee, BSc(Hons), MBBS, MRCP

Genitourinary and HIV Specialist Registrar

Department of HIV

Harrison Wing

Guy’s and St Thomas Hospital NHS Foundation Trust




MJL declares no competing interests.

Julie Fox, BSc(Hons), MBChB, MRCP, MD

HIV consultant and Honorary Senior Lecturer KCL

Department of HIV

Harrison Wing

Guy’s and St Thomas Hospital NHS Foundation Trust




JF has received scientific grants from Gilead Sciences and Merck.


Dr Ming Jie Lee and Dr Julie Fox would like to gratefully acknowledge Dr Jennifer A. Johnson, Dr Paul Sax, Dr Rebecca Plank, Dr Michael Brady, Dr Emily Cheserem, and Dr Claire M. Naftalin, the previous contributors to this monograph. JAJ declares that she has no competing interests. PS serves as a consultant for Abbott, BMS, Gilead, GSK, Merck, and Janssen. He receives grant support from BMS, Gilead, and GSK. EC has been sponsored by GlaxoSmithKline for several conferences and sponsored by Gilead Sciences, Bristol-Myers Squibb Pharmaceuticals, and Abbott Laboratories to attend various educational programs. CMN has been sponsored by Bristol-Myers Squibb Pharmaceuticals to attend an educational program. CMN is an author of a reference cited in this monograph. MB not disclosed. RP declares that she has no competing interests.

Peer reviewers

Professor Margaret Johnson, MB BS, MD, FRCP

Clinical Director

HIV/AIDS Services

Royal Free Hampstead NHS Trust




MJ declares that she has no competing interests.

William Rodriguez, MD

Chief Medical Officer

Foundation for Innovative New Diagnostics (FIND)

Campus Biotech




Not disclosed.

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