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Updated: Aug 15, 2026
07:10
Humanized NOD/SCID/IL2rγnull (hu-NSG) Mouse Model for HIV Replication and Latency Studies
Published on: January 7, 2019
Seroconversion following nonoccupational postexposure prophylaxis against HIV
Michelle E Roland1, Torsten B Neilands, Melissa R Krone
1Positive Health Program at San Francisco General Hospital, California, USA. mroland@php.ucsf.edu
Summary
Post-exposure prophylaxis (PEP) for human immunodeficiency virus (HIV) is not fully effective after nonoccupational exposures. Primary prevention strategies remain crucial for reducing HIV transmission risks.
Area of Science:
- Infectious Diseases
- Virology
- Public Health
Background:
- Antiretroviral post-exposure prophylaxis (PEP) is effective for occupational human immunodeficiency virus (HIV) exposures.
- Its effectiveness for nonoccupational exposures is unknown due to differing circumstances.
- This study investigated HIV seroconversion after nonoccupational PEP.
Purpose of the Study:
- To describe the occurrence and circumstances of HIV seroconversion after nonoccupational PEP.
- To assess the effectiveness of PEP in nonoccupational settings.
- To highlight challenges in evaluating PEP efficacy in non-isolated exposure scenarios.
Main Methods:
- A nonrandomized trial involving HIV-uninfected individuals with potential HIV exposures.
- Participants received a 28-day antiretroviral therapy regimen and counseling.
- HIV antibody levels were measured 12 weeks post-PEP initiation.
Main Results:
- Of 702 evaluable subjects, 7 (1%) seroconverted to HIV.
- Three cases may indicate PEP failure; four cases had indeterminate sources due to subsequent exposures or baseline HIV RNA.
- Genetic concordance with exposure source could not be assessed.
Conclusions:
- PEP is not completely effective in preventing HIV infection after nonoccupational exposure.
- Primary prevention remains essential for reducing HIV transmission.
- Challenges in determining PEP failure versus new exposures complicate efficacy studies.
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