Funding pressures and the rise of chronic illnesses such as heart disease are the top "danger zones" for global health in 2012, the head of the World Health Organization, Margaret Chan, said on Monday.
The director general used an address to the World Health Assembly, the annual meeting of the WHO's decision-making body, to warn that squeezed government finances could see the focus stray from the fight against diseases like HIV/AIDS -- where a 2015 target for treatment already looks to be missed.
"Saving a life with a vaccine is unquestionably far cheaper and more immediate than keeping someone with AIDS alive. It is also less demanding on health services," said Chan.
"Taxpayers and parliamentarians want to see quick, tangible, and measurable results that demonstrate payback for the money.
"This can be dangerous, especially for a disease like HIV/AIDS."
Chan said there was "good reason" to believe that a United Nations target of having 15 million people on antiretroviral therapy by 2015 will not be met.
The director general, who is expected to be officially reappointed for a second term on Wednesday, also warned of the "longest dark shadow" over progress in global health: non communicable diseases including cardiovascular disease and diabetes.
WHO statistics released last week showed obesity rates nearly doubled across the globe from 1980 to 2008.
One in three adults suffers from high blood pressure and one in every ten has diabetes.
Chronic diseases are on the rise in developing countries in particular, where people are living longer and where salty, processed foods have become more widespread.
"These are the diseases that break the bank," said Chan.
"These are the diseases that can cancel out the gains of modernization and development.
"These are the diseases that can set back poverty alleviation, pushing millions of people below the poverty line each year."
Explore further: UN summit on non-communicable diseases should learn from global AIDS response