Inaccurate Public Health Messages from Politicians = Very Bad

Those of you who either follow public health and/or know South Africa have certainly heard about the "AIDS-denialist" bent of former President Mbeki and his Health Minister, Manto Tshabalala-Msimang. If you don't, basically the two of them (mainly the latter with support from the former) put forth a view that HIV does not cause AIDS and that anti-retrovirals on balance confer negative health benefits (see this earlier post). Clearly, this flies in the face of science and common-sense. But what are the effects of these espousals on risky behaviors? Do people actually listen to this stuff? Did these beliefs lead to changes in behavior and, ominously, more HIV infections, in the general public?

A recent paper by Eduard Grebe and Nicoli Nattrass at the University of Cape Town strongly suggests that denialist claims played a role in reducing condom use among a sample of young adults in South Africa. Here's the abstract:

This paper uses multivariate logistic regressions to explore: (1) potential socio-economic, cultural, psychological and political determinants of AIDS conspiracy beliefs among young adults in Cape Town; and (2) whether these beliefs matter for unsafe sex. Membership of a religious organisation reduced the odds of believing AIDS origin conspiracy theories by more than a third, whereas serious psychological distress more than doubled it and belief in witchcraft tripled the odds among Africans. Political factors mattered, but in ways that differed by gender. Tertiary education and relatively high household income reduced the odds of believing AIDS conspiracies for African women (but not men) and trust in President Mbeki's health minister (relative to her successor) increased the odds sevenfold for African men (but not women). Never having heard of the Treatment Action Campaign (TAC), the pro-science activist group that opposed Mbeki on AIDS, tripled the odds of believing AIDS conspiracies for African women (but not men). Controlling for demographic, attitudinal and relationship variables, the odds of using a condom were halved amongst female African AIDS conspiracy believers, whereas for African men, never having heard of TAC and holding AIDS denialist beliefs were the key determinants of unsafe sex.

The study makes a few good points:
1) Bad information can lead to bad public health outcomes. (The ridiculous measles vaccines-autism scare did something very similar, more on that later)
2) These negative effects can depend on the level of education. (Here it is decreasing in education. For the measles vaccine-autism link, more educated people were more likely to decline the vaccine for their kids. Again, more on that later)
3) Social organizations, NGOs and activists can play a major role in reducing the effects of noisy or bad information.