What is a “global disease?” Are cholera, HIV/AIDS, malaria, and TB global diseases?

Jean Lanjouw, an economist from Yale University, has argued that we should distinguish between global diseases and other diseases that target poor countries. Dr. Lanjouw defines a global disease as a disease that exists both in developed and developing countries. Diseases that mainly afflict poor countries are not truly global in scope. According to WHO figures, over 99 percent of worldwide cases of malaria, measles, and diarrheal diseases are found in low- and middle-income countries.

The distinction between global and other diseases becomes important when we consider ethical and practical questions relating to how we respond to public health crises. The drugs that treat cholera, HIV/AIDS, malaria, tuberculosis and other diseases often cost a lot of money to produce and distribute, and, in many cases, the drug companies that produce them have sole ownership rights to their production and sale. This means that agreements need to be struck with drug companies if people want to make sure that treatments are available at prices poorer countries can afford.

As we noted earlier, recently drug companies have agreed to offer medicines to treat HIV/AIDS at substantially reduced prices in certain poor countries. One reason the drug companies can afford to do this is because they can recover part of the cost of providing the drugs at reduced prices in poor countries by charging normal, higher prices in developed countries. Put differently, drug companies can afford to cut the cost of AIDS treatments in a country like South Africa because they can charge full-price for the same drugs in the United States. U.S. consumers, in effect, subsidize the sale of drugs to South Africa.

But there is no meaningful market in developed countries for drugs that treat cholera and malaria, because those diseases are largely found in poorer regions of the world. Without the opportunity to make sales in rich-country markets, drug companies sometimes lack the financial motivation either to develop new drugs for the treatment of diseases common to developing countries or to cut prices for existing drugs. Drug manufacturers believe they will be unable to recover the high costs of drug research and development through sales of new drugs in countries where people cannot afford to pay a lot for treatment. This means that some of the money to develop new drugs will have to come from other sources, not exclusively from private drug companies. Additional funding is also needed to help purchase and distribute drugs. Generating the necessary funds will be a major challenge for governments in the coming years.

Next: Link between TB and HIV