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effect of prep during seroconversion



What would the effect be if in a period of seroconversion (unknown to yourself) you would take PREP for a Short time (like to cover the course of a holiday). Would it effect the onset of ARS symptoms, spread them in time, or delay them? Is anything know about that?

Thank you

Kind regards


Hello. Thank you for contacting us with your question.

We gather that you would like to know what effect initiating PrEP would have on symptoms of seroconversion, it you started it without knowing you were HIV positive.

All of the information I'm sharing here comes from guidelines for doctors here in British Columbia regarding the use of PrEP and PEP:

When you present to your doctor asking to be put on PrEP (Pre-exposure Prophylaxis), the first step before starting treatment is to confirm negative HIV status, using a 4th generation HIV Ag/Ab enzyme immunoassay (EIA). If symptoms suggestive of acute HIV infection within the previous 6 weeks are present, and/or history of high-risk condomless sex in the previous month, a pooled nucleic acid amplification test (NAAT) for HIV RNA is recommended. (1) This guideline is intended to prevent the situation you describe where you are starting on PrEP but are already HIV positive.

The time from initiation of daily oral doses of TDF/FTC (PrEP) to maximal protection against HIV infection is unknown. However, pharmacokinetic data from HIV-infected individuals suggest that steady-state level in the rectal mucosa is reached after 7 days, and in the cervico-vaginal mucosa after 20 days of initiating therapy. If PrEP is to be halted, the optimal duration of PrEP continuation after a recent sexual exposure is unclear. PrEP should be continued for at least 48 hours after a high risk exposure, however, continued use for as long as 28 days after a high risk exposure is recommended by some groups. PrEP should be part of a combination prevention strategy that includes behavioural interventions such as condoms and risk reduction counseling. (1) This suggests that if you intend to use PrEP to cover the course of a holiday, you should start it at least 7 days (if you are male) before your holiday begins and continue it for 28 days after your holiday ends. If possible, don't depend exclusively on PrEP for HIV prevention.

While I couldn't find information specifically about PrEP delaying onset of seroconversion symptoms, PrEP has a very similar composition to PEP (Post-exposure Prophylaxis). When a person takes PEP, the window period for any given HIV test begins at the end of the course of PEP treatment because if the medication was not successful in eliminating the virus, then it may be suppressing it. Remember that these are the same medications that people who have HIV use to suppress the virus to undetectable levels. Based on this, we can logically assume that starting a PrEP treatment when you are already infected with HIV could delay your seroconversion symptoms.

Regards, AIDS Vancouver Helpline Volunteer, Dyson