Post on 12-Dec-2014
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60 million people, infected since 198139.5 million people are living with HIV 4.3 million new infections in 2006 Over 28 million have died since 1981 Ten new infections occur every minute
FactsSpecial Features of HIVHuman Immune System ResponseIdeal HIV VaccineCurrent AchievementsProspective
FactsFacts
AIDS kills more people than any other infectious disease Impact on economics Unreliable pharmacotherapy HIV is the best studied pathogen Yet we don’t have any vaccine for it
FactsSpecial Features of HIVHuman Immune System ResponseIdeal HIV VaccineCurrent AchievementsProspective
Special Features of HIV
HIV is highly mutable Genetically diverse
population of viruses Too variable epitopes
of the viral envelope Masking of gp120 High levels of viral replication Long latent period of infection
Special Features of HIV
GP 120
Slide 7.37
FactsSpecial Features of HIVHuman Immune System ResponseCurrent AchievementsAn Ideal HIV VaccineProspective
Human Immune System Response
Humeral immunity
Human Immune System Response
Cell-mediated immunity
FactsSpecial Features of HIVHuman Immune System ResponseCurrent AchievementsAn Ideal HIV VaccineProspective
Current Achievements
Since 2000
30 vaccine versions have been tried Many clinical trials are ongoing in
developing countries Large scale AIDS vaccine
trials could be conducted
Current Achievements
Live Attenuated
Whole Killed
Live Vector
Re-combinant Proteins
DNA Vaccines
Pseudovirion
Vaccine Types
Current Achievements
Whole, Killed HIV
Not under study in primates
No useful immunity
Difficult to maintain viral configuration
Difficult to make large quantities
Live, Attenuated HIV
Studied in non-human primates
Has pathogenic potentiality
Live Vector Vaccines
Phase I and II trials
Inserting HIV or SIV genes into viruses or bacteria
Effective humoral and cellular immune responses
Recombinant Viral Protein Vaccines
Phase III
Uses viral surface
antigens as
immunogens
Uses genetically
engineered bacteria,
yeasts, insects or cell
cultures
Naked DNA Vaccines
Stages I , I/II and II
Synthesizing antigens using
host-cell’s machinery
Presented on the cell
surface with host MHC class
I and class II molecules
Pseudovirions
Pre-clinical trialsVirus-like particlesSelf-assembling,
non- replicating, virus-sized structures
FactsSpecial Features of HIVHuman Immune System ResponseCurrent AchievementsAn Ideal HIV VaccineProspective
An Ideal HIV VaccineAn Ideal HIV Vaccine
SterilizingLong-term controlled infection
Transient Infection
Altruistic vaccine
Epidemiological Aspect
Individual Aspect
An Ideal HIV VaccineAn Ideal HIV Vaccine
Efficacy
Protection from infection
Sterilizing immunity Protection from
disease
Reduction in set point viral loads
Time after infection
Vir
al lo
adIdeal vaccine
Peak
Set point
Sub optimal vaccine
FactsSpecial Features of HIVHuman Immune System ResponseCurrent StandAn Ideal HIV VaccineProspective
Total New Infections Averted By An AIDS VaccineN
ew in
fect
ions
in m
illi
on
Vaccine introduction
Base
Low scenario
Medium scenario
High scenario
Total new infections averted by an AIDS vaccine between 2015-2030
30% efficacy
20% coverage
50% efficacy
30% coverage
70% efficacy
40% coverage
5.5 million
28 million
17 million
28 million
Is an AIDS vaccine really Preparable?
Is an AIDS vaccine really Preparable?
In 1984 researchers predicted that a
vaccine was right around the corner…
INTERNATIONAL HEALTH SECURITY 2007
…..HIV/AIDS threatens the stability of entire
regions and nations…. While there are major
efforts under way to find
a vaccine and to expand access to
affordable treatments, much more still needs to
be done…
What To Do Now?
Conclusions The scale of HIV problem is huge Humanity needs an effective vaccine to end the
pandemic Developing an HIV vaccine is a laborious task HIV vaccines on different stages of trials are
only partially effective The best primary prevention up till now is :
- Health education
- Personal protection
Acknowledgments
Dr. Seyed Mohsen Mahmoodi Dr. Abdel Hamid Elhawary Mr. Mohammad Reza Rahimi Dr. Rizwana Sheikh
THANK THANK YOU!!!YOU!!!
You Can Visit My Website: www.mahmoodi.org