Where do we stand on HIV-AIDS on World AIDS Day: December 1?
According to Dr. Rajat Goyal, the head of the International AIDS Vaccine Initiative’s (IAVI) India operations:
“The 28th annual World AIDS Day is upon us and it serves as a reminder that while we have achieved great milestones in containing the disease a lot still needs to be done. Millions of the world’s most vulnerable people, families and communities are being left behind: those most affected face societal discrimination and stigma. Even with much better access to and use of existing tools to fight the epidemic, millions more in developing countries are likely to contract HIV in decades to come. The disease continues to kill 1.2 million people every year and another 1.5 million become HIV positive. A vaccine is a critical part of any long-term strategy to end the AIDS epidemic. Only then will we make serious inroads against HIV-AIDS, in the way that we successfully conquered polio and smallpox.”
What is the position of HIV-AIDS in India today?
- Our country has the third highest number of estimated people living with HIV in the world. The estimated number of people living with HIV/AIDS in India was 2.08 million (20.9 lakhs in 2011) out of which an enormous 86% of whom were in 15-49 years age group. Children less than 15 years of age accounted for 7% (1.45 lakh) of all infections in 2011. Of all HIV infections, 39% (8.16 lakh) were among women. (Source: NACO Annual Report 2014-15)
- The HIV epidemic in India is concentrated, with high prevalence among high-risk groups (i.e., Intravenous drug users, sex workers, men who have sex with men and transgender people), moderate prevalence among bridge populations(i.e., People, who, through close proximity to high risk groups are at the risk of contracting HIV. Quite often they are clients or partners of male and female sex workers. Truckers and migrant labours are major bridge populations), and low prevalence among general population. (Source: NACO Annual Report 2013-14).
- Three primary routes of HIV transmission in India: (i) unprotected sex,? (ii) injecting drug use, & (iii) unprotected anal sex between men. (Source: NACO Annual Report 2013-14)
Why is an AIDS Vaccine important?
Vaccines are powerful public health tool and have proven to be the world’s most effective and cost effective preventive mechanism
- A 70% effective AIDS vaccine could reduce new infections by 40% in its first 10 years; and 50% in its first 25 years.
- Globally, about 36.9 million people reported to be living with AIDS, in the year 2014. (Source: UNAIDS)
- AIDS is the #1 killer of women of reproductive age, globally
- AIDS is the #2 killer of adolescents, globally
How is India positioned as part of global efforts to discover a vaccine?
- India’s strength lies in its rich pool of scientists and healthcare professionals who are globally competitive, a competitive scientific infrastructure and a thriving bio pharma industry. Additionally, the Government of India is committed to this critically important cause.
Why is the making of a vaccine so challenging?
- HIV is a complex pathogen
- Part of what makes HIV such a difficult virus to combat is its ability to furiously mutate the trimeric envelope protein on its outer surface. This high mutation rate gives rise to multiple HIV subtypes that circulate around the globe, allowing the virus to escape the responses that human immune systems mount against it.
- That the virus could mutate and regain its pathogenicity has rendered approaches like using attenuated versions of the pathogens to immunize people or using a killed or inactivated virus adopted for making other vaccines like measles, polio and influenza, unsuccessful thus far. Scientists are learning to be as wily as the virus to discover new ways to combat it.
- There are other challenges unique to HIV. Quickly following transmission, the virus disseminates and establishes a persistent infection, including hidden reservoirs from which it can strike again at any time. The opportunity for a vaccine-induced response to prevent infection or to control the initial, limited infection is thus short-lived.
- Scientists still don’t understand how to elicit specific, durable, and protective immune responses against HIV.
Where are we today on the road to a viable AIDS Vaccine for humans?
Progress during the past five years is spurring creative and promising new approaches. Scientists have isolated and closely analyzed dozens of exceptionally potent antibodies that neutralize a broad spectrum of HIV variants circulating around the world.
In addition, several preclinical studies of novel vectors for HIV vaccine have produced promising results, far exceeding the performance in similar studies of candidates that are today in clinical trials..
Breakthrough discoveries are leading to more refined and targeted vaccine designs
Some scientists are making significant progress by employing reverse-engineering or structure-assisted vaccine discovery. This new approach starts with isolating broadly neutralizing antibodies from chronically infected HIV patients whose immune systems produce them.
Even the clinical trials with disappointing results are and will continue to be important. The lessons learned in HIV vaccine research are also helping to fight flu, malaria, cancer, Ebola
Another major advance has been the scientists ability to obtain an atomic-level image of the HIV envelope trimer, the principal target for broadly neutralizing antibodies
Collectively, these efforts are paving the way for a nontraditional immunoprophylaxis that can protect against HIV infection without depending on the lengthy and complex antibody maturation process required to generate broadly neutralizing antibodies through immunization.
Source: IAVI; photo coutesy flickr.com/bastique
About IAVI: The International AIDS Vaccine Initiative (known as IAVI) is a global not-for-profit, public-private partnership working to accelerate the development of vaccines to prevent HIV infection and AIDS. IAVI’s work is centered around the needs of those regions and populations most in need of an AIDS vaccine. With more than 15 years of in-country experience, IAVI partners to expand the R&D capacity and leadership in India as well as Africa region. IAVI continues to conduct and facilitate training, mentoring, knowledge sharing and technology transfer with in regions and across regions globally. IAVI pioneered the Public-Private Product Development Partnership (PDP) model that brings together researchers from academia, the private sector and government with the common goal of advancing the best vaccine candidates down the research and development pipeline.
Some World Stats:
- According to the World Health Organization (WHO), more than 75 million people have become infected with the HIV virus and an estimated 40.2 million people have died of AIDS-related illnesses since reporting for the epidemic began in 1981 (UNAIDS 2015, p. 40).
- 1.2 million people died in 2014, down 42% from a peak of 2 million in 2004. (UNAIDS 2015, p. 40)
- 2.0 million people became newly infected with HIV in 2014, down 35% since infections reached 3.1 million in 2000. (UNAIDS 2015a, p. 32)
- Around 5,500 people are newly infected with HIV every day. (UNAIDS 2015b, Epi Slides)
- About 66% are in Sub-Saharan Africa
- About 600 are in children under 15 years of age
- About 5,000 are in adults aged 15 years and older, of whom:
- Almost 48% are among women
- About 30% are among young people (15-24)
- In nine countries, 10% or more of adults are estimated to be HIV-positive. South Africa has the highest number of people living with HIV in the world (6.8 million). Swaziland has the highest prevalence rate in the world (27.7%). (Source : UN AIDS)
- Globally, 20 countries account for 80% of people living with HIV. (UNAIDS 2015a, p. 98)