Nearly 200 million people around the world are estimated to be on the move, amounting to what the United Nations AIDS Program calls the greatest human flux in history. UNAIDS says many of these people play an important role in the global HIV epidemic, but are difficult to identify and treat.
About three-fourths of the world's transients - perhaps 150 million people - are voluntary migrants seeking better economic conditions. Another 40 million are involuntary refugees from strife and natural disasters. An estimated one to two million are forced into prostitution or labor.
By the nature of their existence, the mobile and the displaced often live in unhealthy conditions, at high risk for disease. The president of the Washington-based international health promotion organization Global Health Council, Dr. Nils Dulaire, says they are one of the major hidden pathways for the spread of AIDS. "They are some of the most at-risk people in the world," he said. "They have very limited opportunities to protect themselves. They have no economic base of their own. We're seeing that migrants and displaced are some of the highest risk groups for HIV/AIDS."
The bulk of the transients, the migrant workers, live away from the norms of their home communities and are often tempted by potentially deadly sexual opportunities. For example, UNAIDS says more than one-fourth of infected Filipinos and two-fifths of Bangladeshis with HIV have worked in other countries. The Special U.N. envoy for AIDS in Africa, Stephen Lewis of Canada, told the Barcelona conference that migrants are helping worsen that continent's epidemic.
"The agricultural workers and the resource based workers who leave their families, live alone as young men, come back to the families, infect the wives or other partners, have presented a nightmarish scenario for the patterns of movement of the pandemic across the continent," said Mr. Lewis.
The international relief organization CARE attributes Cambodia's high infection rate, three percent of its adult population, to refugee movements.
"Cambodia has recently recovered from many years of civil war," said Kim Green, CARE's HIV coordinator in Cambodia. "It's very poor. People, to survive, need to move. A lot of people go to the urban areas and they go to the border, and what we've found is that HIV prevalence is the highest between Thailand and Cambodia."
UNAIDS says efforts to tackle the mobile population problem are complicated by the fact that few countries collect information about them. This is often because migrants, particularly the economic ones, are illegal in their host countries. The Global Health Council's Nils Dulaire says their status forces them to stay out of sight and away from AIDS prevention and treatment programs.
"It's very difficult to provide services to those people, and very often, the governments that are providing the services to their own people don't wish to also further attract immigrants by providing services to the illegals," said Mr. Dulaire. "That's a problem we've seen even in the United States of America. Unfortunately, that is an enormously counterproductive approach from a public health standpoint."
Dr. Dulaire says an infection from a hidden population spreads just as fast as one from legal residents and therefore, should be identified and treated without stigmatizing the source.
Last year, the U.N. General Assembly Special Session on AIDS committed member nations to design national, regional, and international strategies to make HIV programs accessible to mobile populations. International Organization for Migration official Mary Haour-Knipe says that for such strategies to work, governments must grant migrants the right to health care, and she emphasizes that countries cannot work alone on this problem.
"We need to link countries of origin, transit, and destination. People travel. They no longer move once and forever as they used to do. They keep going back and forth," she said.
UNAIDS describes several existing regional HIV programs for migrants in its recent report on the pandemic. The agency runs one in five west and central African countries. Mexico's government collaborates with several Central American governments and private groups. The private European project "AIDS and Mobility" works in 14 countries, while the Association of Southeast Asian Nations is working toward a five-year plan to tackle HIV among mobile populations in its region.