Jeff also offers a couple of case studies.
AIDS victims in 1987: Philippines 135 / Thailand 112
In 1991 the WHO predicted the Philippines would have 80,000 to 90,000 cases and Thailand 60,000 to 80,000 AIDS victims.
Thailand promoted the use of condoms in massive campaigns where Catholic Philippines promoted 'Abstinence' and 'Be faithful'.
The prognosis of the WHO was wrong for both countries:
1999: Philippines 1,005 / Thailand 755,000 AIDS victims
Source: British Medical Journal, volume 328, April 10th 2004
Here is another case:
Take for example a March 2004 article in the medical journal, Studies in Family Planning (cited by the Zenit News Agency, June 26, 2004). Titled "Condom Promotion for AIDS Prevention in the Developing World: Is It Working?," the piece was a meta-review of the scientific literature on the question.
The results shocked condom advocates. In the article, researchers Sanny Chen and Norman Hearst noted that, "In many sub-Saharan African countries, high HIV transmission rates have continued despite high rates of condom use." In fact, they continued, "No clear examples have emerged yet of a country that has turned back a generalized epidemic primarily by means of condom distribution."
No surprise, then, that Botswana, Zimbabwe, Kenya, and South Africa — the nations with the highest levels of condom availability — continue to have the highest rates of HIV prevalence ("The White House Initiative to Combat AIDS: Learning from Uganda," Joseph Loconte, Executive Summary Backgrounder).
While Patrick has a similar take on the disparity of influence by the Church in his Latin Lovers Conversation.
According to the United Nations, there are many conversations occurring in Latin America similar to the one below: