HIV post exposure prophylaxis (PEP) Flashcards
What are the 3 broad categories through which HIV exposure may occur?
1) Occupational exposure
2) Community non-occupational exposure
3) Sexual exposure
How long does it take for HIV to start to replicate once it has crossed the mucosal barrier?
Up to FORTY EIGHT (48) hours
When is HIV first detected in the blood?
FIVE (5) days
Within what time frame has PEP been shown to reduce dissemination and replication of HIV virus?
start within SEVENTY TWO (72) hours
UK surveillance data of occupational exposure to HIV - summarise
Since 2004 all occupational exposures started on PEP have no new cases HIV
Brazil study that support PEPSE use - summarise
MSM in Brazil
Overall HIV incidence similar to expected
PEP group less seroconversion than non-PEP group
What were the percentages for seroconversion for the PEP group vs non PEP group in the PEP Brazil study?
1.4% vs 7.5%
PEP vs nonpep
Describe the EXPLORE study for PEPSE?
MSM in USA
behavioural intervention trial
No difference HIV seroconversion between PEP vs nonPEP group
What data is there to support PEP in exposure through PWID?
LIMITED data
What are the 4 reasons for PEPSE failing?
1) DELAYED ART start
2) POOR or non- adherence
3) Further HIGH-RISK SEX after PEP stops
4) Early PRIMARY HIV INFECTION already established
For PEPSE, what was the adherence to single tablet regimen vs twice daily?
71% TDF/FTC/EVG/r vs
57% RAL based (BD) or
39% PI based (BD)
When was the last recorded occupational HIV transmission?
1999
What 3 factors contribute to the risk of HIV transmission through sexual exposure?
1) TYPE of sex
2) HIV viral load of INDEX partner
3) SUSCEPTIBILITY of recipient if partner not virologically suppressed ie concomitant STI/GENITAL ULCER DISEASE
HPTN 052 trial - describe what this trial was?
Randomised control trial (RCT)
Heterosexual serodiscordant couples
HPTN 052 trial - what were the outcomes?
8 linked transmissions
- 4 prior to full viral suppression
- 4 related to treatment failure/detectable VL
- None if VL undetectable
PARTNER trial - describe what this trial was?
- Europe
- Prospective observational
- Gay and HETEROSEXUAL, discordant couples
PARTNER trial - what were the outcomes?
888 couples
No linked transmissions
PARTNER 2 - describe this trial?
- Extension of PARTNER to improve understanding of transmission risk for MSM
- Prospective observational
- MSM
PARTNER 2 - what were the outcomes?
782 couples
No linked transmissions
OPPOSITES ATTRACT - describe this trial
Small observational
MSM
OPPOSITES ATTRACT - what were the outcomes?
232 couples
No linked transmission
What FOUR trials support the statement U=U?
HPTN 052
PARTNER
PARTNER 2
OPPOSITES ATTRACT
What is the estimated prevalence of DETECTABLE HIV viraemia in England for MSM?
23/1000
What is the estimated prevalence of DETECTABLE HIV viraemia in England for PWID?
6.7/1000
Is the estimated prevalence of DETECTABLE HIV viraemia for PWID higher for men or women?
WOMEN
11 per 1000 vs 5 per 1000
estimated prevalence of DETECTABLE HIV viraemia in heterosexual non-Black African MEN?
Very low
0.2 per 1000
estimated prevalence of DETECTABLE HIV viraemia in heterosexual non-Black African WOMEN?
Very low
0.1 per 1000
Is the estimated prevalence of DETECTABLE HIV viraemia for Black Africans higher for men or women?
WOMEN
8.7 per 1000 vs 5.8 per 1000
What is the risk of HIV transmission with RECEPTIVE anal sex + EJACULATION?
1 in 65
What is the risk of HIV transmission with RECEPTIVE anal sex + no ejaculation?
1 in 170
What is the risk of HIV transmission with INSERTIVE anal sex + CIRCUMCISION?
1 in 909
What is the risk of HIV transmission with INSERTIVE anal sex + no circumcision?
1 in 161
Which specific exposures involving anal sex have very similar risks?
Receptive + no ejaculation
(1 in 170)
Insertive + no circumcision
(1 in 161)
What is the risk of HIV transmission with RECEPTIVE vaginal sex?
1 in 1000
What is the risk of HIV transmission with INSERTIVE vaginal sex?
1 in 1219
Which is highest risk, receptive or insertive VAGINAL sex?
Receptive
1 in 1000 vs 1 in 1219
What TWO exposure types have risk of HIV transmission 1 in 1000?
receptive vaginal
mucocutaneous
What is the risk of HIV transmission with SEMEN SPLASH into eye?
<1 in 10000
What is the risk of HIV transmission with ORAL sex?
< 1 in 10 000
What is the risk of HIV transmission with a human BITE?
< 1 in 10 000
What is the risk of HIV transmission with blood TRANSFUSION?
1 in 1 (ie 100%)
What is the risk of HIV transmission with NEEDLESTICK injury?
1 in 333
What is the risk of HIV transmission with sharing injecting equipment inc chemsex?
1 in 149
What THREE exposure types have risk of HIV transmission <1 in 10 000?
SEMEN SPLASH to eye
ORAL sex
Human BITE
How do you calculate risk of HIV transmission?
Risk of HIV transmission =
Risk per type of EXPOSURE x risk that source is HIV positive with detectable viral load (ie population)
What FIVE factors in the index case increase the risk of HIV transmission if NOT on ART?
1) High VL
2) Breaches of mucosal barrier
3) Menstruation
4) Pregnancy/post partum
5) STI or genital ulcer disease
If the index case has a detectable viral load what impact does this have on the risk of HIV transmission?
2.9 fold increase per act with each log10 increase
Through what THREE scenarios might an occupational exposure occur?
Contact with bodily fluids or tissue
1) PERCUTANEOUS
2) MUCOUS MEMBRANE (or non-intact skin)
3) BITE
Which Body fluids are implicated in the transmission of HIV?
Blood, semen, vaginal secretions
CSF
Synovial, pleural, peritoneal, pericardial or amniotic fluid
Which Body fluids are NOT implicated in the transmission of HIV?
faeces, nasal secretions, saliva, gastric secretions, sputum, sweat, tears, urine or vomit.
In which situation might there be a risk of HIV transmission in the bodily fluids not typically implicated in infection?
If there is blood in them
What FOUR factors increase the risk of HIV seroconversion in the event of percutaneous injury?
1) DEEP injury
2) VISIBLE BLOOD on device
3) Needle in VEIN or ARTERY
4) AIDS in index case
What is the risk of HIV transmission through non-intact skin?
Negligible
Have there been any reported cases of HIV transmission through non-intact skin?
No
What is the risk of HIV transmission through SPITTING and BITING?
Spitting - NO risk
Biting - NEGLIGIBLE (increased if blood in saliva and high VL index case)
What factors have been present when HIV transmission occurred through a bite?
Index case: HIGH viral load, BLOOD in mouth and DEEP or MULTIPLE bites
HIV outbreak in PWID in Glasgow - describe
Identified 2015 Ongoing HIV prevalence increased 0.1% to 4.8% overall 1.1% to 10.8% Glasgow city centre
What are the THREE main drugs used in chemise?
1) crystal methamphetamine
2) GHB/GBL
3) ephedrine
What is the reason for taking ‘chems’?
SUSTAIN or ENHANCE the experience of sex
What is an alternative term for ‘injecting’ drugs in the context of chemsex?
‘slamming’
What proportion of MSM partake in chemsex?
17%
What proportion of MSM partaking in chemsex, inject drugs?
10%
There are FOUR categories of PEP recommendation - what are they?
RECOMMENDED
CONSIDER
GENERALLY NOT recommended
NOT RECOMMENDED
What is the definition of ‘PEP RECOMMENDED’?
Benefits of PEP outweigh risk
PEP should be given unless clear reason not to
What is the definition of ‘CONSIDER PEP’?
RISK of HIV transmission LOW
Risk vs benefit balance less clear
requires CASE by CASE assessment
What is the definition of ‘PEP GENERALLY NOT RECOMMENDED’?
risk of HIV transmission VERY LOW
potential TOXICITY of PEP likely outweighs benefit
PEP will very rarely be given
What is the definition of ‘PEP NOT RECOMMENDED’?
NEGLIGIBLE risk of HIV
PEP should NOT be given
What information is important to get from the index case of a potential HIV transmission?
HIV status
Viral load
ART - on or off
Past virological failure or resistance
If the index case is known to be HIV positive with detectable VL what is the calculation used to establish risk of transmission?
1 x risk per exposure
ie Risk of HIV transmission = risk that source is HIV positive with a detectable HIV viral load X risk per exposure
What study types support U=U with regards to sexual exposure?
RCT
Observational studies
What THREE factors in the PLWHIV need to be met to guarantee U=U?
1) UNDETECTABLE VL
2) ART SIX (6) months
3) Good ADHERENCE
Is PEP recommended for oral sex with ejaculation?
NO
What is the risk of HIV transmission for oral sex with ejaculation?
<1/10 000
What factors may increase the risk of HIV transmission for oral sex?
Recent dental procedures
Pharyngitis
Chemotherapy
Periodontal disease