From Prof Jeffrey Sachs.

Sir, I appreciate the letter of Prof Debarati Guha-Sapir (February 7), who stresses that urgent help for the poor should be directed not only at HIV/Aids, TB and malaria but also at other killers such as diarrhoeal disease, acute respiratory infections and vaccine-preventable diseases.

But the good professor overstates the case. The Commission on Macroeconomics and Health of the World Health Organisation undertook almost 100 background studies over the past two years on the massive disease problems of the poorest countries. The commission reached a consensus that "vertical programmes" (such as the international programmes StopTB and Roll Back Malaria and the national efforts they support) as well as support for primary health systems both have their critical role - and indeed work best in tandem.

Even more important, the world does not have to choose between the two approaches. The commission report shows that for a very small fraction of rich countries' gross national product - roughly one penny for every $10 of income in the rich countries - it would be possible to scale up health interventions in poor countries enough to save 8m lives a year, assuming that the donor support is combined with scaled-up, realistic efforts by the poor countries themselves.

These increased investments in health would include control of the three great pandemic diseases (Aids, TB and malaria) as well as the diseases to which Prof Guha-Sapir draws our attention. The economic, social, security and humanitarian benefits are so high that these investments are indeed likely to be made both by donors and recipient countries, once they are properly understood and elaborated. The commission report may be downloaded in full at http://www.cmhealth.org

Jeffrey D. Sachs, Centre for International Development, Harvard University, Cambridge, Mass 02138, US Copyright Financial Times Limited 2002. All Rights Reserved.