A historic opportunity to eradicate the disease is in danger of being squandered, say experts

A historic opportunity to eradicate Aids is in danger of being squandered if the world does not come up with the necessary funds to finish the job, experts warned yesterday.

Latest figures show that almost 50 per cent of people with the disease now have access to antiretroviral drugs. The number of HIV-infected individuals in treatment rose to 6.6 million last year but is still a long way short of the 14.2 million who need it.

The increase has contributed to a 21 per cent fall in new infections since 1997 and a 21 per cent fall in deaths. Deaths now stand at 1.8 million, their lowest level since peaking in 2005 .

Unaids, which released the figures yesterday in its annual World Aids Day report, How to Get to Zero, said new infections had fallen by more than two thirds in Botswana since the late Nineties, where treatment with antiretrovirals covers 80 per cent of the population – the most extensive of any country in Africa. "The end may be in sight if countries invest smartly," the report said.

Scientists showed last year that treatment reduces the risk of an infected person transmitting the virus to their partner by 96 per cent, suggesting that Aids could be defeated. In June, the UN Secretary-General, Ban Ki-Moon, called for a global commitment to eliminate Aids by 2020 by rolling out drugs to all who needed them – "Zero new infections, zero stigma and zero Aids-related deaths," he said.

Earlier this month, the US Secretary of State, Hillary Clinton, held out the prospect of an "Aids-free generation" with three measures: preventing babies from being infected at birth, voluntary male circumcision (which provides 60 per cent protection to men) and universal drug treatment. She announced an extra $60m for Pepfar, the President's Emergency Plan for Aids Relief, to fund pilot studies and called on other donors to join the effort.

Barack Obama is expected to make a further announcement on 1 December, World Aids Day.

Despite such pledges, the economic woes of Western donor nations meant that their contributions to the global effort on Aids prevention and treatment fell 10 per cent in 2010. Although the UN High Level summit on Aids last June agreed to raise the total available to between $22 and $24bn in order to double the number on treatment and end mother-to-child transmission by 2015, there is doubt about whether countries signing up to the declaration will keep their promises.

Adrian Lovett, the Europe Director of ONE, the global advocacy organisation, said: "Maintaining the status quo is not enough. We are only halfway there in the fight against Aids. This year, for the first time, evidence shows us that it is possible to change the trajectory of the epidemic. The success stories of countries such as Botswana show just what is possible.

"The beginning of the end of Aids may just be in sight, but it will require a new determination from African leaders, other governments and the private sector to finish the job they have started. Now would be the worst possible time to walk away from the fight."

Michel Sidibe, executive director of Unaids, said: "We are on the verge of a significant breakthrough. Even in a very difficult financial crisis, countries are delivering results in the Aids response."

The number of people living with HIV has reached a record 34 million, thanks to the life saving effects of antiretroviral drugs. Sub-Saharan Africa has seen the most dramatic improvement, with a 20 per cent rise in people undergoing treatment between 2009 and 2010.

New infections are also declining as a result of changes in sexual behaviour with 21 out of 24 of the worst affected countries recording falls as young people have reduced their numbers of sexual partners and increased their use of condoms.