An estimated 25,000 scientists, politicians, physicians and activists were present on Sunday at the opening of the six-day 17^th International AIDS Conference held for the first time in Mexico.

It is the second large conference in the 27-year history of the disease and the largest in a developing country.

Figures released before the conference showed that the number of people with HIV has slightly gone down worldwide partly because more and more people in developing countries have access to antiretroviral medication needed to prevent the condition from developing. There is no vaccine or drug to cure HIV, but existing drugs give infected people the chance to a nearly normal life.

There are currently around 33 million people infected with the virus worldwide, 70 percent of which living in Africa because access to the right drugs is improving but there are not enough health care workers to administer them and to monitor the population. Also, 25 million people have died since AIDS first became known.

In addition, other figures involving this time the US situation, showed that the number of people being infected with HIV virus is about 40 percent higher than previously estimated, which is more than ironic considering the fact that the Bush administration has spent $19 billion to fight HIV overseas in the past five years through a program called the President’s Emergency Plan for AIDS Relief.

“AIDS is the most complex, the most challenging and probably the most demanding infectious disease humanity has ever had to face. We dare not to let down our guard. This is an unforgiving epidemic. We are going to be in this for a long haul,” Margaret Chan, director general of the United Nations’ World Health Organization (WHO) said Sunday at the opening.

Peter Piot, executive director of the UN agency UNAIDS supported the same idea saying the situation is far from being considered optimistic. “Every day, almost three times as many people become newly infected with HIV as those who start taking antiretroviral therapy,” he said.

Public figures attending the conference include UN Secretary General Ban Ki-moon, Scottish rock singer Annie Lennox and former US president Bill Clinton who is a key person in the campaign to slash the price of anti-HIV drugs to developing countries. Seth Berkley, president of the New York-based International AIDS Vaccine Initiative, Dr. Anthony Fauci, head of the US National Institute of Allergy and Infectious Diseases and other leading world researchers are expected to speak at the conference.

Topics expected to be of main concern for the scientists at the conference include the current global HIV rates and ways to improve access of the public to the antiretroviral drugs, and also ways to increase the number of medical stuff monitoring the infected people. There are also expected some studies. For example, evidence has emerged that male circumcision can help prevent HIV infection among men – a finding of great significance in southern Africa, the epicenter of the pandemic.