hiv “myths, controversies and challenges”
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HIV “Myths, controversies and challenges”. Dr Emmanuel Nsutebu Consultant Infectious Diseases Physician Tropical and Infectious Diseases Unit Royal Liverpool Hospital. “10 questions ....”. 1. What is the difference b/w HIV and AIDS 2. What is the origin? 3. How is it transmitted? - PowerPoint PPT PresentationTRANSCRIPT
Dr Emmanuel NsutebuConsultant Infectious Diseases
PhysicianTropical and Infectious Diseases Unit
Royal Liverpool Hospital
HIV “Myths, controversies and challenges”
“10 questions ....”1. What is the difference b/w HIV and AIDS2. What is the origin?3. How is it transmitted?4. Does the risk of transmission vary?5. Can you know when a person got infected?6. Is lengthy pretest counselling needed
before a test is done?7.How is HIV treated?8. Can it be cured?9. What is the life expectancy?10. What about a vaccine and is there hope?
How many people are affected? Globally 34 million PLHAs, 1.7M deaths a year, 2.5M
new infections a year 15 million eligible for treatment and 8 million on
treatment. 24 million cases in Africa 5% adult prevalence in Cameroon (2011) – 900000
PLHA
UK – 70000 PLHA
No. Of new cases and deathsFalling due to success of treatment
1. What is the difference b/w HIV and AIDS?
Not the same thing but related. AIDS is a stage of HIV infection.
NOT ALL HIV INFECTION = AIDS
Most people with HIV have no symptoms
2. Origin? Jump from chimpanzees to humans - SIV
Figure 1
Source: The Lancet Infectious Diseases 2011; 11:45-56 (DOI:10.1016/S1473-3099(10)70186-9)
Terms and Conditions
3. How is HIV transmitted?Unprotected sex – 70% of infectionsMother to child transmission – mum must
be positive – during pregnancy, at birth or during breastfeeding!
Intravenous drug use – sharing needlesBlood transfusion and other blood productsMedical equipment
Mother to child transmission
30% risk of transmission reduced to <2% with ARVS
How is HIV not transmitted?CutleryMosquitoesKissingHugging
4. Does the risk of transmission vary?Varies depending on
Positive personNegative personRoute of transmission
Sex 3/1000 but can happen with first contact
Transmission to women easierIV drug user high risk
5. Can you know when a person acquired the infection?No but can guess!!!
Apr 21, 2023Understanding HIV Treatment and adherence.
4-8 wks Up to 12 years 2-3 years
No symptoms Symptoms AIDS
Death
1000
500
0
CD4 count HIV viral load
200
2-12 mo
2 million
0
Viral load & CD4 after HIV Infection[without treatment]
Time
HIVinfection
J. Coffin, XI International Conf. on AIDS, Vancouver, 1996
Development of AIDS is like an Development of AIDS is like an impending train wreckimpending train wreck
Viral Load = Speed of the train Viral Load = Speed of the train CD4 count = Distance from cliffCD4 count = Distance from cliff
Infections and cancer!
6. Is lengthy pretest counselling needed?An HIV test is a routine test!!!
7. How is HIV treated and it is effective?
HIV Replication Cycle and Sites of Drug Activity
clinicaloptions.com/hiv
Capsidproteinsand viral
RNA
CD4Receptor
Viral RNA
New HIVparticles
Protease
Attachment Uncoating ReverseTranscription
Integration Transcription Translation
ReverseTranscriptase
Unintegrateddouble strandedViral DNA
Integratedviral DNA
ViralmRNA
Integrase
gag-polpolyprotein
1 2 3 4 56
Assembly andRelease
Protease InhibitorsNRTIs
NNRTIs
Nucleus
Cellular DNA
CCR5or
CXCR4co-receptor
HIV Virions
nRTI
Fusion Inhibitors
At least 3 drugs to stop the virus from multiplying
HIV Medication TimelineBetween ’87 and ’95 (9 years), 4 antiretrovials were launched.
Since ’95 (11 years), 25 new products have been introduced!!
NNRTI
’’8787 ’’9191 ’’9292 ’’9494 ’’9595 ’’9696 ’’9797 ’’9898 ’’9999 ‘‘0000’’8888 ’’8989 ’’9090
NRTINRTI
FIFI
saquinavirsaquinavir
indinavirindinavirKaletraKaletra
zalcitabinezalcitabine
stavudine
’’0101
emtricitabine/emtricitabine/tenofovirtenofovir
enfuvirtideenfuvirtide
‘‘0202 ‘‘0404’’9393
amprenaviramprenavir
‘‘0505 ‘‘0606‘‘0303
zidovudine
emtricitabineemtricitabine
abacavir/lamivudine/zidovudine
lamivudine/zidovudinelamivudine/zidovudine
delavirdine
nevirapine
abacavir
efavirenztenofovirtenofovir
ritonavir
saquinavirsaquinavir
atazanaviratazanavir
fosamprenavirfosamprenavir
nelfinavirnelfinavir darunavirdarunavir
tipranavirtipranavir
PIPI
didanosinedidanosine
didanosinedidanosine
Corrections Curriculum Development, NY/NJ AETC
lamivudine
Many drugs available and more in development – outlook is good!
Treatment & Treatment as prevention
Most patients on one or two tablets a day!
Apr 21, 2023Understanding HIV Treatment and adherence.
After HIV treatment (ARVs): effect on CD4 and viral load
1-12 yrs +1-6 moChronic
Infection
Start treatment
1000
500
0
CD4+ cells/mm3
viral load (RNA)copies/mL
200
2 million
0
+ 1-40+ years !!
< 50 copies/mL
Viral load <50 copies/mL
Time
8. What is life expectancy like?We don’t know for sure however we have
estimates....HIV survival similar to other chronic
diseases!Life expectancy at 25 years diagnosis
estimated to be 70 years
9. What about a cure?
10. What about a vaccine?Problem is variability of the virus!!!Stays one step ahead of immune system!!!
What are challenges?
Early diagnosisAccess to treatment in developing
countries
Thank you [email protected]