“Many studies examining HIV prevalence declines have implicated sexual behavior change but do not appear to have adequately considered the contribution of rural-urban migration.”
By Andrew Mambondiyani:
It is an accepted fact in the AIDS community that fewer people in eastern and southern Africa are now being infected with the HIV than in the 1980’s and 90’s.
The accepted explanation is that people have altered their sexual behavior; they now have fewer sexual partners outside of marriage or maintain stable relationships, and use condoms more often if they do have sex with non-regular partners.
However, recent research in southern Africa suggests this explanation is seriously incomplete, according to Prof Michael Loevinsohn, an ecologist, and epidemiologist based in the Netherlands, who led this research.
Prof Loevinsohn has been involved in the connections between health, agriculture, and the environment in eastern and southern Africa for almost 30 years. His research brings in a new approach to the fight against HIV and Aids.
In an interview in Antwerp, Belgium recently, Prof Loevinsohn said the research focused on countries in southern Africa– Malawi, Zambia, and Zimbabwe, which have among the highest HIV infection rates on the continent.
“The studies find that migration by rural people to urban centers, accelerated by food insecurity, has played an important and till now largely unrecognized part in HIV’s decline,” Prof Loevinsohn revealed.
And he added: “The proportion of people infected is typically lower in villages than in towns and cities so when people move there, they dilute the prevalence. The studies find that migration rates increased during the food crisis that struck much of southern Africa in the first years of the century. It was during this period that HIV infection rates declined markedly in urban centers”.
In Malawi, he said, it was found that HIV prevalence increased sharply in the rural areas where hunger was most severe, likely as a result of people, women, in particular, being pushed into survival sex – in exchange for food or work.
“And the women who moved to the towns and cities, while lowering the prevalence there, were themselves at higher risk of infection than had they remained in the villages,” he said.
Prof Loevinsohn said evidence was emerging that similar things have been happening in Zambia and Zimbabwe.
“Exactly how much rural migration has contributed to HIV’s decline across the region compared to sexual behavior change is not known because researchers haven’t been asking the right questions. However, the new take on HIV’s history is showing that secure access to food and livelihood plays a significant role in the course of the disease. And that opens up new ways to confront HIV,” he said.
In his report titled The 2001-03 Famine and the Dynamics of HIV in Malawi: A Natural Experiment published by the journal PLOS ONE, Prof Loevinsohn revealed that food security had deteriorated for many people in developing regions facing high and volatile food prices.
“Without effective and equitable responses, the situation is likely to worsen due to diminishing access to land and water, competition from non-food uses of agricultural products, and the effects of climate change and variability. Understanding how this will affect the burden and distribution of major diseases such as HIV are critical,” he noted.
The Malawi famine, the study revealed, appeared to have had a substantial effect on HIV’s dynamics and demography. Prof Loevinsohn discovered that poverty and inequality, commonly considered structural determinants of HIV epidemics, can change rapidly, apparently transmitting their effects with little lag.
And it emerged that epidemic patterns risk being misread if such social and economic changes were ignored.
“Many studies examining HIV prevalence declines have implicated sexual behavior change but do not appear to have adequately considered the contribution of rural-urban migration. The evidence from Malawi, which links actions that undermined people’s food security to changes in the prevalence and distribution of HIV infections, suggests new opportunities for prevention,” the study reveals.