Updated at 8.03pm: The number of children infected with HIV in Asia has fallen, new research from a leading Aids research group shows. According to the latest report from Therapeutics Research Education and Aids Training (Treat Asia), fewer Asian children are catching the disease. But it warned that treatment for more than 120,000 HIV-positive children in the region still remained a 'daunting challenge'. 'Scarce and prohibitively expensive paediatric drug formulations and inadequate paediatric treatment education are just two factors that have led to a situation that only a small fraction of children who need antiretroviral drugs are receiving them,' the report said in its latest issue. The newsletter quotes Dr Jintanat Ananworanich, a paediatrician specialising in treating infants with HIV/Aids. She said Asia faced unique challenges in helping children with the disease. 'Treating children in Thailand is very different to treating them in the United States, and the appropriate regimens and doses may not be the same,' explained Dr Ananworanich. She said many paediatricians were treating children in the same way as adults - but the drug dosages were not always correct for children. The human immunodeficiency virus - HIV - causes a patient's immune system to break down - often leading to full-blown Aids, which is fatal. Currently one of the most promising therapies is called highly active anti-retroviral therapy, also known as Aids cocktail therapy, which combines two nucleoside analogue drugs and one protease inhibitor to delay a patient's progression to Aids. The therapy dramatically reduces concentration of virus in bloodstream but cannot guarantee to eliminate every virus. It is not certain whether patients taking the drugs may still be able to transmit HIV. It often results in severe side effects. The Joint United Nations Programme on HIV and Aids (UNAIDS) and the World Health Organisation (WHO) estimated that there were 40.3 million people living with HIV around the world by the end of last year. Of these 2.3 million were children under the age of 15, and about 700,000 of them were infected last year. HIV/Aids has hit Africa harder than any other region. Describing Southern Africa as 'the epicentre of the HIV and Aids pandemic' globally, the International Federation of Red Cross and Red Crescent Societies on Friday said more than 10 million people were living with HIV in Southern Africa. The societies jointly launched a new five-year plan in Johannesburg on Thursday which aims to reinforce the fight against the HIV/Aids epidemic in 10 southern African countries, where more than four million children have been orphaned as a result of Aids. A child can be infected with HIV through mother-to-child transmission or unprotected contact with blood and body fluids, such as semen during unprotected sex. Experts say a high proportion of the children with the disease come from poorer areas, where many of their mothers have no access to medical care or proper education about safe-sex practices. Moreover, some women do not seek early treatment, which could help prevent an HIV infection spreading to their babies. In Asia, health authorities are also looking at better ways to prevent mothers transmitting the disease to their children. Experts told a three-day Asian Aids Conference, which opened last month, that in the East Asia-Pacific region 31,000 children under the age of 15 were infected with HIV. They noted that 1.5 million young people have been orphaned by the disease. Thailand, for example, has had 32,000 children infected with HIV - 12,000 of whom developed full-blown Aids and died. Dr Ananworanich said the real figure was probably higher. 'Experts in Thailand feel that the total number of children with HIV is probably closer to 50,000.' United States Ambassador to Vietnam Michael Marines, one of 250 delegates at the East Asia and Pacific Regional Consultation on Children and HIV/Aids, said infant HIV-Aids patients were still being neglected. 'The issue of orphans and vulnerable children has not been a major part of the debate surrounding HIV/Aids in Asia. I believe it is the time for that to change,' he stressed. The conference set prevention of mother-to-child transmission of HIV as its first priority. Its delegates said more should be done to give children with Aids better access to drug treatment. It also argued that more should also be done to improve the lives of orphaned children. However, the lack of good data on children and young people is greatly hindering Asia's response to the epidemic. Dr Ananworanich also said drug resistance among children with HIV remained a serious problem. 'To follow children with HIV, we employ clinical exams and white blood cell counts, which is the best measure we have for clinical outcomes,' she explained. 'But even when children are under treatment, we really don't know whether they are developing drug resistance unless we know what their viral loads are.' Moreover, doctors are often unsure of what dosages of HIV-drugs should be given to children. 'The ideal dose for children on many protease inhibitors in the second-line regimen is really not known, and the formulation is not ideal for them,' she explained. Another problem was that drugs were expensive and often difficult to obtain. 'One protease inhibitor named Kaletra comes in a liquid formulation and has the best data for treatment outcome, but it is very expensive. We also don't have access to Kaletra, so I think this will be the main problem for us in the future,' she said. Liquid formulation is believed to be the easiest way to give children HIV drugs. It is also most precise way for administering doses. But it was not always available. The mainland is also coming to terms with the number of infants who have the disease. China's official figures put the number of HIV-positive children under the age of 15 at 1,259 last year. Half of them are from central Henan province, where villages were devastated by Aids after poor farmers became infected from selling blood in unsanitary blood-collection programmes. However, it is believed that the real number of those infected is likely to be much higher. The mainland government has provided free treatment to rural Aids patients and urban sufferers in financial difficulty. With the help of Clinton Foundation, paediatric drugs have became available to children in Henan province since the middle of last year. In January this year, the Chinese government along with WHO and UNAids jointly estimated that 650,000 people were infected with HIV in China, of those about 75,000 were suffering from Aids. The Chinese government also estimates that 260,000 children could be orphaned by Aids by 2010. However, this number is disputed as Aids activists and NGO workers in Henan province estimate that as many as a million children in that province alone are or will become orphaned by the disease. This will have terrible social consequences. Already, many school-age HIV/Aids orphans have been forced out of school because they could no longer afford the school fees or because they had to go to work and care for sick parents. This situation is a concern of former US president Bill Clinton, who has established an HIV/Aids Initiative programme to help such children. 'Last year, we realised 500,000 kids were going to die of Aids and only 25,000 were getting the medicine,' Mr Clinton told The Guardian last month. 'I understand why others got priority, but all these kids were dying. 'Now, I can tell you that there are 2,000 kids who are alive today who wouldn't have been [had we not helped them], and I have found it immensely rewarding.'