According to the latest report by the WHO, UNICEF and UNAIDS Report on the global HIV/AIDS response indicates that increased access to HIV services resulted in a 15 per cent reduction of new infections over the past decade and a 22 per cent decline in AIDS-related deaths in the last five years.

"It has taken the world ten years to achieve this level of momentum," says Gottfried Hirnschall, director of WHO's HIV department. "There is now a very real possibility of getting ahead of the epidemic. But this can only be achieved by both sustaining and accelerating this momentum over the next decade and beyond."

Advances in HIV science and programme innovations over the past year add hope for future progress. In times of economic austerity it will be essential to rapidly apply new science, technologies and approaches to improve the efficiency and effectiveness of HIV programmes in countries.

The report highlights what is already working: Improved access to HIV testing services enabled 61 per cent of pregnant women in eastern and southern Africa to receive testing and counselling for HIV - up from 14 per cent in 2005; Close to half (48 per cent) of pregnant women in need receive effective medicines to prevent mother-to-child transmission of HIV (PMTCT) in 2010;  antiretroviral therapy (ART), which not only improves the health and well-being of the infected people but also stops further HIV transmission, is available now for 6.65 million people in low- and middle-income countries, accounting for 47 per cent of the 14.2 million people eligible to receive it.

When people are healthier, they are better able to cope financially. The report acknowledges that investment in HIV services could lead to total gains of up to US$ 34 billion by 2020 in increased economic activity and productivity, more than offsetting the costs of ART programmes.

“2011 has been a game changing year. With new science, unprecedented political leadership and continued progress in the AIDS response, countries have a window of opportunity to seize this momentum and take their responses to the next level,” said Paul De Lay, Deputy Executive Director, Programme, UNAIDS. “By investing wisely, countries can increase efficiencies, reduce costs and improve on results. However, gains made to date are being threatened by a decline in resources for AIDS.”

The report also points to what still needs to be done: More than half of the people who need antiretroviral therapy in low- and middle-income countries are still unable to access it. Many of them do not even know that they have HIV.; Despite the growing body of evidence as to what countries need to focus on to make a real impact on their epidemics, some are still not tailoring their programmes for those who are most at risk and in need. In many cases, groups including adolescent girls, people who inject drugs, men who have sex with men, transgender people, sex workers, prisoners and migrants remain unable to access HIV prevention and treatment services; Worldwide, the vast majority (64 per cent) of people aged 15-24 living with HIV today are female. The rate is even higher in sub-Saharan Africa where girls and young women make up 71 per cent of all young people living with HIV - essentially because prevention strategies are not reaching them.

Key populations are continually marginalized. In Eastern Europe and Central Asia, more than 60 per cent of those living with HIV are people who inject drugs. But injecting drug users account for only 22 per cent of those receiving ART.

Although better services to prevent mother to child transmission of HIV have averted some 350 000 new infections among children, some 3.4 million children are living with HIV - many of whom lack HIV treatment. Only about one in four children in need of HIV treatment in low- and middle-income countries received it in 2010, as compared to 1 in 2 adults.

"While there have been gains in treatment, care and support available to adults, we note that progress for children is slower," says Leila Pakkala, Director of the UNICEF Office in Geneva. “The coverage of HIV interventions for children remains alarmingly low. Through concerted action and equity-focused strategies, we must make sure that global efforts are working for children as well as adults”.

In 2010, HIV epidemics and responses in different parts of the world vary with shifting trends, progress rates and outcomes.

Sub-Saharan Africa recorded the biggest overall annual increase – 30 per cent - in the number of people accessing ART. Three countries (Botswana, Namibia and Rwanda) have achieved universal coverage (80 per cent) for HIV prevention, treatment and care services. The regional ART coverage rate stood at 49 per cent at the end of 2010. Approximately 50 per cent of pregnant women living with HIV receive treatment to prevent mother-to child transmission of HIV. And 21 per cent of children in need are able to get paediatric HIV treatments. There were 1.9 million new infections in the region, where 22.9 million people are living with HIV. There are some major disparities in progress between different parts of the region. Countries in Eastern and Southern Africa have reached much higher coverage rates for ART (56 per cent) and PMTCT (64 per cent) than countries in Western and Central Africa (30 per cent and 18 per cent respectively).

Asia shows a stabilizing epidemic overall, but new infections are very high in some communities. Of the 4.8 million people living with HIV in Asia, nearly half (49 per cent) are in India. Antiretroviral treatment coverage is increasing with 39 per cent of adults and children in need of HIV treatment having access. Coverage of PMTCT services is relatively low – (16 per cent).

Eastern Europe and Central Asia presents a dramatic growth in HIV, with new infections increasing by 250% in the past decade. Over 90% of these infections occur in just two countries: Russia and Ukraine. The region demonstrates high coverage rates for PMTCT and paediatric HIV treatment (with 78% and 65% coverage rates respectively). However, ART coverage is very low at 23%, particularly among the most affected people - the ones who inject drugs.

Middle East and North Africa records the highest number of HIV infections ever in the region (59 000) in 2010, which represents a 36 per cent increase over the past year. Coverage of HIV services are very low in the region: 10 per cent for ART, 5 per cent for paediatric treatment and 4 per cent for PMTCT.

Latin America and the Caribbean have a stabilizing epidemic with 1.5 million living with HIV in Latin America and 200 000 in the Caribbean. HIV is predominantly among networks of men who have sex with men in Latin America. In the Caribbean though, women are the more affected group accounting for 53 per cent of people living with HIV. The region has ART coverage of 63 per cent for adults and 39 per cent for children. Coverage for effective PMTCT regimen is relatively high at 74 per cent.

Countries are already showing marked efficiency gains in HIV programmes: South Africa reduced HIV drug costs by more than 50 per cent over a two-year period by implementing a new tendering strategy for procurement. Uganda saved US$ 2 million by shifting to simpler paediatric regimens. Such efficiencies are promoted through Treatment 2.0 - an initiative launched by WHO and UNAIDS in 2010 to promote simpler, cheaper and easier-to-deliver HIV treatment and diagnostic tools, combined with decentralized services that are supported by communities.

A WHO, UNAIDS, UNICEF "Elimination Initiative" aims to eliminate new HIV infections among children by 2015 and keep their mothers alive.

WHO is developing new guidance on the strategic use of antiretroviral drugs for both prevention and treatment.

WHO's "Global Health Sector Strategy on HIV/AIDS, 2011-2015", endorsed by the World Health Assembly in May 2011 highlights the importance of continuing efforts to optimize HIV treatment and "combination" prevention - the use of a range of different approaches to reduce people's risk of infection.