On May 18, 1997, US President Bill Clinton spoke at the Morgan State University, lauding the effective anti-HIV (Human Immunodeficiency Virus) measures that helped in improving the quality of life in people infected by the virus. But he insisted that only effective, preventive strategies can eliminate the threat of AIDS from the world. A year later in 1998, the world observed its very first World AIDS Vaccine Day, to commemorate Clinton’s historic speech. The tradition continues to this day to focus attention on AIDS prevention and to raise awareness about the same.

What is AIDS?

AIDS or Acquired Immune Deficiency Syndrome is an immune disorder, which destroys the body’s immune system, lowering the person’s resistance to infection and cancers. The HIV attacks and destroys immunity, which wards off germs, infections and other pathogens that make you sick. When the body is unable to defend itself, it becomes vulnerable to infections and diseases.

The early 1980s and 90s were fraught by an unprecedented rise in AIDS cases in America and all over the world, but the first-ever global pandemic of AIDS occurred in 1920s in the Congo. From there, HIV spread to the rest of the world through immigration and unprotected sex.

Scientists believe that HIV originated in chimpanzees, who were affected by SIV or Simian Immunodeficiency Virus that was attacking their immune system and causing AIDS-like symptoms in them. The virus is believed to have jumped species when hunters who poached chimpanzees got infected by the blood of these animals through the cuts and wounds on their hand.

Why Do We Need AIDS Vaccine?

Today, there are over 36.7 million people infected with the HIV/AIDS. The government of India estimates that about 2.40 million Indians are living with HIV, of which 83 percent are in the 15-49 age bracket. The HIV/AIDS pandemic is the most catastrophic health crisis the world has ever faced, and the prevalence levels for this virus may rise globally in the years to come.

Today we have antiretroviral therapy or ART for the treatment of HIV, which is lifesaving boon for many living with the virus. Pre-Exposure prophylaxis or (PrEP) is also being given to people who are at risk of contracting HIV. But according to UNAIDS, an estimated 1.8 million people were newly infected with HIV as recently as 2016.

In the fight against infectious diseases like AIDS, vaccines our best bet. Till now, only vaccines have helped the world eradicate dreadful diseases like smallpox, polio, measles and yellow fever, which have killed and maimed millions. As the adage goes, prevention is indeed better than cure when it comes to AIDS.

Experts also believe that vaccine is the best way to eradicate HIV/AIDS because the commonest modes of transmission of the virus –unprotected sex, needle-sharing, breastfeeding, etc. – cannot be controlled or eliminated.

Do We Have Effective AIDS Vaccines Today?

Currently, there are no vaccines to prevent AIDS, but clinical trials are underway. Although we have succeeded at developing vaccines for common childhood diseases, developing one for AIDS is a different ball game altogether.

Despite all the efforts that are being put in, the development of a successful HIV prevention vaccine is fraught with many challenges. Repeated attempts to find a successful vaccine have all failed, like VaxGen’s AIDSVAXgp120 vaccine and MRKAd5 HIV-1 Gag/Pol/Nef vaccine.

Why vaccine development for AIDS has not even achieved partial success can be attributed to many reasons. The overarching reason being the way HIV evades the human immune system.

• HIV disables the cells that can be responsible for fighting it.

• HIV hides from the immune system for many years by integrating its viral genome into the chromosome of the infected cells.

• HIV can hide the protein components, which makes it recognisable to the immune system. That way, it can enter the human body and make it difficult for the immune system to respond effectively.

• HIV is a diverse virus group. It is also rapidly changing itself, especially its outer envelope. It helps the virus outsmart the immune system by evading its natural and protective mechanisms.

These reasons make finding an effective vaccine for the HIV one of the biggest medical challenges. Theoretically, one of the most logical approaches to finding a fool-proof vaccine is to identify the human body’s best protective mechanism and to construct a vaccine which can stimulate the response. But clinical trials are underway to find an effective vaccine.

Is It Possible to Get HIV From a Vaccine?

Preventive vaccines won’t cause HIV to an uninfected person. The current vaccines which are being used in clinical trials do not contain HIV. In the 25-year history of the AIDS vaccine, 30,000 people have participated in the studies, and no one has been infected with the virus.

Today, thousands of brains and ample funding has been put into finding successful AIDS vaccine. All we need is patience. Together with ART and other preventive measures, an effective preventive HIV/AIDS vaccine will help us eliminate the scourge of AIDS once and for all. The observance of World AIDS Vaccine Day since 1998 is a reminder of our relentless fight to find a permanent solution to the AIDS problem and send it packing like we did smallpox, measles and polio.

(References: HIV/AIDS Vaccines How long must humanity wait?, Recent update in HIV vaccine development)

(The above story first appeared on LatestLY on May 18, 2018 01:32 PM IST. For more news and updates on politics, world, sports, entertainment and lifestyle, log on to our website latestly.com).