At the July 2012 International AIDS Conference in Washington DC, I joined U.S. Secretary of State Hillary Rodham Clinton and other prominent leaders, activists and scientists in calling for an AIDS-free generation. The optimism at the conference was palpable—this is what happens when there are tangible results for people.

There is much to celebrate. More than eight million people living with HIV are now receiving antiretroviral therapy, up from just 400,000 in 2003. New HIV infections have fallen by more than 25 percent over the past decade. In many parts of the world, the AIDS epidemic is stabilizing or in decline. This progress seemed unimaginable just a decade ago.

Science has given us new tools for HIV prevention, such as pre-exposure prophylaxis, voluntary medical male circumcision and rapid, home-based HIV testing. The impact of antiretroviral treatment in preventing new HIV infections is now unmistakable. Developments in vaccine research show considerable promise.

In more than 80 low and middle income countries, domestic investments for AIDS increased by over 50 percent between 2006 and 2011. The BRICS countries (Brazil, Russia, India, China and South Africa) now fund, on average, more than 75 percent of their own AIDS responses.

I left the conference with a renewed sense of hope that—together—the international community has recommitted to the vision of "getting to zero": zero new HIV infections, zero discrimination, and zero AIDS-related deaths.

The challenge before us now is not how but how soon we will bring an end to the epidemic. To accelerate this vision into reality, we will need to listen and respond to the voices of the voiceless.

Women. Too often, women are not at the table when it comes to determining the future course of the epidemic. Violence against women must be stopped. Barriers must be removed so all women can access health services. There are almost no new HIV infections among children born in richer countries, as access to reproductive and maternal health services for women has brought new HIV infections among children to nearly zero. There is no reason why this cannot be replicated in other parts of the world. Yet in 2011, there were 330,000 children born with HIV. Women living with HIV must have access to antiretroviral treatment and reproductive health services—for themselves foremost and for protecting their children and partners.

Young people. Showing tremendous leadership in stopping AIDS, today's generation of young people is more aware and empowered to act against HIV than previous ones, and the results are promising. Young people are choosing to have fewer partners, use condoms and wait longer before becoming sexually active. However, their voices are not resonating loud enough to achieve maximum impact. Nearly 40 percent of new HIV infections are among young people. Young girls are 2.5 times more likely to be infected with HIV than their male peers in the Caribbean. In addition, a whole new generation of young people who were infected at birth are becoming adults, bringing a new perspective to living with HIV.

Sex workers. There are 116 countries and territories that criminalize some aspect of sex work. This is a profession that has thrived through the millennia—yet women, men and transgender people involved in sex work do not have basic protections, let alone their human rights. A sex worker faced with violence is less likely to be able to negotiate condom use. The threat of constant arrest, violence and discrimination looms large over sex workers and therefore they are unlikely to come forward and access HIV and health services.

People who inject drugs. There are about 16 million people who inject drugs—of which three million are estimated to be living with HIV. Outside of sub-Saharan Africa, nearly 30 percent of all new HIV infections are among people who inject drugs, with two-thirds living in Eastern Europe, East and South-east Asia and Latin America. Yet, evidence-based HIV treatment and prevention services are not provided to people who use drugs in most parts of the world. Only two needles and syringes are available to drug users each month, only eight out of 100 people who use drugs have access to opioid substitution therapy, which weans them off from injecting. Only four out of 100 people living with HIV who inject drugs have access to antiretroviral therapy. Countries that are deeply entrenched in anti-drug rhetoric must accept scientific evidence. Ironically, resources spent on outdated drug prevention and treatment services would be better spent on harm reduction and other proven treatment and prevention services. Networks of drug users often do not get funding from government sources and have to rely on non-state donations to maintain their advocacy work

Men who have sex with men. A similar situation exists for men who have sex with men. Homophobia and transphobia exist in almost every corner of the world. Some 78 countries, territories and areas criminalize same sex relations between consenting adults. This community has remained on the fringes of the global AIDS response, even though they were the forerunners of the AIDS response in the 1980s, demanding action and access to HIV services. In Asia, the odds of men who have sex with men becoming HIV infected are 18 times higher than the heterosexual population, and in Latin America, half of all HIV infections have occurred among men who have sex with men.

Seniors and people with disabilities. There is now growing evidence that HIV is also an issue for older people, as many people on HIV treatment are above the age of 50 and sexually active. People with disabilities account for nearly 15 percent of the world's population, but very few HIV programmes count them in. In a world where conflict, calamities and the ensuing displacement of populations is becoming a daily occurrence, keeping HIV services intact in the face of adversity remains a challenge. The world must not forget that there are more than 34 million people living with HIV—people with faces, families and futures they look forward to. Their voices are paramount in our quest to end AIDS.

At UNAIDS, we believe in ensuring that the rights of the most vulnerable and marginalized are realized. Speaking on their behalf and amplifying their voices is not just our raison d' etre but our moral imperative.

Without giving voice to people living with HIV, sex workers, men who have sex with men, transgender people, women and girls, young people, people who inject drugs, displaced populations and people with disabilities, we cannot—and will not—end AIDS. GHD