LONDON, April 28 (Reuters) - HIV/AIDS has captured world headlines leaving other killer diseases out of the spotlight and under-funded, health experts warn.

Lower-profile illnesses also kill millions of people every year, most of them children, they say.

Respiratory infections kill more than four million annually, diarrhoea kills 2.2 million, one-third of the world's population carries tuberculosis (TB) and malaria kills around 3 million every year.

But experts in the HIV/AIDS field argue the virus needs more money and attention because it kills more people and is more expensive to fight than other diseases.

And they say there is still not enough money spent on combating HIV/AIDS in poor countries.

U.S. academic Robert Black of the John Hopkins School of Public Health in Baltimore, Maryland, told Reuters: "Given the relative magnitude of the problems of AIDS and other infectious diseases, the increase in funding for AIDS has been very large and the funding for other infectious diseases has either not increased or only very selectively increased.

"I would never say that funding for HIV/AIDS should be decreased. There should be more funding for other infectious diseases, in addition."

Elizabeth Mason, director of child and adolescent health at the U.N. World Health Organisation (WHO), said: "If you look at the resources going into child health compared to the resources going into other areas, it is very, very small.

NO BETTER IN 20 YEARS

"I've been working in Africa for 25 years, and I'm not sure we are better off than we were 20 years ago."

Some health specialists argue that AIDS is privileged in funding terms due to its high profile in wealthier countries.

Debarati Sapir, an epidemiologist at the Catholic University of Louvain in Belgium, told AlertNet: "I think (AIDS funding and publicity) is overdone."

But at UNAIDS -- the U.N. body working on HIV/AIDS -- communications and resources director Achmat Dangor said: "In Africa and Latin America AIDS is the biggest cause of death, twice more than malaria and four times more than TB.

"I know it is odious to make comparisons between human mortality, but the fact is that AIDS erodes human capacity far more rapidly than other diseases."

Rosie Vanek, communications officer at the Global Fund to Fight AIDS, Tuberculosis and Malaria said it was not useful to think of AIDS as stealing the limelight from other diseases, since it was more expensive to fight.

She estimated that HIV/AIDS needed $11.5 billion by 2007, well above the $2.6 billion for malaria or the $0.8 billion required to fight TB.

SCARCE RESOURCES

In an environment of scarce resources for health care in developing countries, some experts argue AIDS funding helps fight illnesses that often affect HIV-positive people, such as TB and pneumonia.

WHO spokesman Colin Mathers said: "There is a risk that the focus on HIV will divert scarce resources, medical personnel particularly, in countries where they are needed for a broad range of diseases.

"On the other hand, the funding that comes into HIV can lift the whole health system and benefit other diseases."

Manica Balasegaram, a doctor for aid agency Doctors without Borders, told Reuters: "The high profile given to HIV/AIDS has helped to drive research and the treatment of patients. I hope this will lead the way for progress against other killer diseases like malaria and tuberculosis.

"We still have a long way to go in providing HIV/AIDS treatment to the majority of the people who need it -- the world's poor and marginalised."

((Editing by Janet Lawrence))

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