I have been fortunate enough to be the main photographer for the Global Business Coalition Against AIDS (GBC) for the last three years. This is a growing global body made up of over 220 companies who have decided to become involved in combating AIDS. It is a reaction largely prompted by government neglect and a corporate realization that not only does this pandemic threaten economies, but it is in fact the greatest threat to human life on the planet today.

My agency, Getty Images, is a member of this organization, and based on my previous work in the field, Getty Images donates my services to the GBC once or twice a year. My job for them thus far has been to go to the four most affected regions in the world and assemble a visual document of conditions.

Thus far I have been to South Africa, Ukraine, China and India to cover the disease, as well as visiting many other countries as part of my normal assignment work for various media. No trip has been longer than 10 days in the field; all have involved at least 3,000km (nearly 2,000 miles) in distance and I have taken an average of eight flights in each place.

In other words, these trips have been a whirlwind of experiences and have each resulted in a library of over 2,000 images for the GBC and its partners. In writing for The Digital Journalist I have chosen four pictures from these regions and decided to write briefly on why these images stood out for me.

An AIDS survivor practices yoga, April 1, 2004. in Soweto, South Africa. Brent Stirton

The first image is of a young woman living with full-blown AIDS in Soweto Township, South Africa. She is pictured against the yellow walls of her home doing her daily yoga routine. Eight months prior to this image she was a final stage case and could not speak, get out of bed or even feed herself. After receiving medication she is now healthier and physically fit.

Doctor Brian Brink was doing outreach work in the townships of South Africa and secured her an American sponsor for anti-retroviral meds and this picture is her doing her yoga routine as she embraces her new life, thanks to these meds. You have to remember that this is a country of 5.5 million HIV-positive people in which the president was in public denial of the disease for a long time and in which the current health minister continues to be ridiculed by the global medical community for her prescription of vegetables to combat the disease.

In my opinion, their attitude has been responsible for many hundreds of thousands of new infections and unnecessary deaths. I am a South African, so when I see my people dying in such numbers with such terrible suffering, I cannot help but be appalled by the failures of our leadership with regard to the AIDS pandemic. When you see the life-restoring qualities that access to medicine brings to people's lives, it mystifies you that there is not more effort to provide these meds.

In late 2005, anti retrovirals became available via five government hospitals in the Gauteng province of South Africa for the first time. In a country where millions suffer from being HIV positive, people one can only hope it is a step in the right direction.

Two gay men make out in a Beijing bathroom, Nov. 18, 2004. (Photo by Brent Stirton/Getty Images)

The second image is taken in Beijing, China, and is of two gay men kissing in a bathroom in an underground club. Until 2001, being gay in China was often punishable by imprisonment. People have been held for over 10 years for this alleged crime. Job dismissal, severely limited opportunity and community ostracism are still common. Because of public stigma, very few men are openly gay in China. This has resulted in less openness about HIV and less sharing of information about the disease. This is an incredibly closed group of people and is very difficult to communicate the dangers of unprotected sex. I got to the men in the photo by working through a gay Chinese filmmaker who took me to series of clubs where I met gay men.

The man whose face is visible in the photo is a gay man who is open about his sexuality despite extreme prejudice. He wants to talk about HIV and has had many friends who have died from the disease. The man he is with would not reveal his face for the camera. He is a male prostitute, one of millions of new arrivals from the provinces to the big city. He has no skills, no education and cannot read or write adequately. As a result, he is extremely difficult to communicate with about the dangers of HIV. Most men like him end up as laborers but he makes good money as a rent boy and prefers this. He told me he sleeps with both men and women and even offered his services to my female interpreter. He was ambivalent over condom use.

The Chinese government is in denial about the HIV issues facing their country. I did this story as a tourist since going in officially means very limited access and a government PR tour. China's cheap labor base, which makes China such a player on the world economic stage, is under massive threat from this disease. In a country that is so new to money, ambition and mobility, AIDS is waiting in the wings for an unsuspecting, ill-informed population.

The next image I made in Ukraine in late 2005 shortly after the so-called Orange Revolution. Ukraine is a former communist nation that has experienced all the benefits of a communist doctrine and corrupt government for as long as most of the population can remember. It's a tough country with hard people used to difficult conditions. It is also the place with the fastest acceleration of the AIDS pandemic in the world. The very few Ukrainian medical bodies involved in the study of AIDS state that the disease is currently spread 50 percent through IV drug use and 50 percent through sex. That's up on 70/30 in favor of IV drug use in the last five years.

Tanya, 29, a sex-worker and drug user who is HIV positive, poses on Aug. 12, 2005, in Poltava, Ukraine. The enormous open wound on Tanja's left leg is severe septicemia, caused by the use of needes on her legs. (Photo by: Brent Stirton/Getty Images)

The image depicts Tanja, a commercial sex-worker and IV drug addict in an industrial town called Poltava. She died a month after this picture was taken of complications related to full-blown AIDS. She used to work in a bakery, which closed due to a failing economy and thereafter she worked as a sex-worker for the last five years. She lived with full-blown AIDS and continued to work as a prostitute, hiding her condition. Tanya talked about that life, saying that sometimes in the past wealthy men would seek her out for sex as part of a bizarre "Russian roulette with AIDS" scenario, where they would have unprotected sex and gamble with the odds of contracting HIV.

Tanja shared a one-bedroom apartment with her 11-year-old son. Her son does not go to school and spends his days playing computer games and dreaming about Africa where he says he will enjoy doing nothing. When asked if he knows his mother is an addict he says, "Yes, but I don't want to talk about that." They live with five other sex-workers who are also addicts in a small apartment in a poor neighborhood. Tanya used to weigh 100 kilograms (220 pounds) but has wasted away to nothing. She has severe septicemia on her legs and a rampant addiction. The enormous open wound created on Tanja's leg was as a result of needle use on her legs. When the infection set in, her collapsing immune system was unable to combat it. Tanja's young son continues to live in the apartment.

India just became the leading AIDS nation, with 5.7 million HIV-positive people. To say the Indian government is not doing much about it would be an understatement. A lot of this is about ignorance, poor education and gender prejudice. While in India, I photographed a young veiled sex-worker hiding in a shelter outside of Delhi. She was 12 the first time her mother asked her to sell her body to raise money for the family. She refused and her mother stabbed her in the stomach and then sent her out to work. A gang rape and two further stabbings by her mother forced her to run away. She continued to work as a sex-worker in Delhi, became a drug addict and eventually lost her mind. She was rescued from a group of pimps by a radical donor-funded anti-AIDS group of ex-addicts and HIV-positive people who have banded together to do something about the spread of the disease. They offer a hospice-style shelter to those affected in Bombay and Delhi. This young woman has six months in the shelter to get her life together.

A girl wearing a white dress stands in a field in Richards Bay, South Africa, March 28, 2004. She is an orphan whose parents died of AIDS. (Photo by: Brent Stirton/Getty Images)

Finally, I include an image of a young AIDS orphan that I shot in South Africa. I wanted to include her because she is symbolic of the 12 million-plus AIDS orphans in Africa today. In her white dress she is a symbol of purity that has been affected by disease through no fault of her own. For me, there is no justification for the impact this disease has had on innocent children worldwide. The fact that we have done so little to combat this effect on so many children is an indictment on us as a civilization. While we haggle over the usual suspects of global politics, millions are dying, half of whom are children, and all this is preventable.

It continues to be a mystery to me how it is acceptable for our leaders and ourselves to think any part of this is okay. Covering AIDS is a test of character for journalists; it is not sexy and new, it can be difficult to publish, but it represents accepting responsibility for publicizing what demands our journalistic attention in our world.

In the cycle of human drama that is constantly presented to a photojournalist, we have to find new ways to tell an old story. If we don't, we risk that story slipping into oblivion and falling off the radar of the collective social responsibility. All I am trying to do is tell that story in the most powerful way I can, under the limited circumstance that time brings to any story.

I am someone who spends at least half my working year shooting in or around conflict zones. They pale into insignificance in comparison to what I am seeing in the world of AIDS.