Wednesday, November 30, 2011

Destroyer nonpareil

I had never really imagined I would sit down to write a blog on AIDS. But then, on World AIDS day, I think back and feel that there has never been such a scourge in mankind's long history. There have been hundreds of infectious diseases that have tormented, killed and plagued humans for years, but none that has been able to withstand every attempt made to suppress it. Be it the great plague, TB, smallpox or polio, scientists have inevitably been able to discover drugs and vaccines to deal with, and in some cases, eradicate the disease. AIDS, however, has been a completely different monster. It was first discovered about thirty years back after a number of cases of a rare form of pneumonia were diagnosed in male patients. All of them seemed to be affected by a immune-suppressor virus and also exhibited a homosexual lifestyle. Soon, incidences of Kaposi Sarcoma, a rare form of cancer, were also found in multiple patients. Then, the disease was thought to be one that solely affected homosexuals and syringe-sharing drug abusers. This, however, turned out to be just the beginning. Hundreds of cases started sprouting up in Africa and Asia where the lifestyle was very different from the high-risk groups in America and Europe. Authorities quickly realised that heterosexuals were just as likely to be affected by this disease. The discovery of this fact completely changed the way the threat was perceived.

The HIV in short for Human immuno-deficiency virus was in many ways similar to a strain of virus found to be causing an immuno disorder in monkeys (SIV). IT was suspected to have resulted from some kind of mutation in the SIV. HIV, a retrovirus, synthesises its DNA from RNA using an enzyme called reverse transcriptase. It is spread mainly through sexual/blood contact via unprotected sex, sharing syringes and to a lesser extent blood transfusion. The virus, after getting into the body, strikes by eliminating immune cells (T-lymphocytes). Although the immune system counters the virus by producing enough antibodies in the beginning, it soon loses the battle as the virus replicates and takes control. Once the immune system is bypassed, the rest of the body is highly susceptible to multiple infections. Although the virus is extremely dangerous and life-threatening once it enters the host, it is one of the least effective when it comes to transmission. The HIV virus can hardly survive for even a few hours outside the human body and cannot be transmitted by physical contact, through the air or by mosquitoes. Considering how destructive the virus can be, it's weak transmissibility is perhaps nature's biggest lifeline.

People who suspect infection undergo either the ELISA (enzyme linked immuno sorbent assay) or the Western Blot Test to detect the virus' presence. These are the two most popular and reliable tests available for the detection of infection. HIV, though, is an extremely difficult pathogen to deal with. It continuously mutates and tends to become drug resistant. Anti-viral drugs therefore, are incapable of providing a cure. However, a lethal combination of powerful anti-viral drugs known as HAART (Highly advanced anti retro-viral therapy) is used to treat HIV-infected patients. By using a combination of drugs, the virus' ability to become resistant is quelled. Infected individuals are thus able to add years to their lives but this treatment comes at an exorbitant cost which very few can afford. Recent studies have found that humans carrying the CCR5 mutation (deletion of a portion on the CCR5 gene) are resistant to HIV infection. This mutation is at the heart of genetic therapy (vaccine and drug research) in many AIDS research centres in the USA and Europe.

While the long struggle for a cure or a vaccine is underway, it is imperative to understand that the best possible approach to fighting this killer disease is by education. Negligence and ignorance are the biggest hurdles. People must be educated on the importance of safe sex and the avoidance of risky practices (drug abuse, promiscuous behaviour). Also, people should learn to care for HIV-infected patients and treat them with respect. They are often ostracised by society for no fault of theirs. It is time for us to learn, educate and advise people to understand the grave consequences of the disease and guide the youngsters so that the spread of the disease can be controlled greatly. In the meanwhile, the extraordinary efforts of scientists all over the world can be directed at finding a highly-elusive cure or vaccine. Man has, after all, successfully survived hundreds of calamities over the centuries. Hope springs eternal.....