While some prevalent diseases, such as cancer and heart disease, appear to be equally distributed throughout the world, other diseases tend to be more regional, based on both genetic predispositions and environment.

In the case of diseases spurred on by environmental factors, such as Neglected Tropical Diseases, which are caused by poor living conditions, and COPD, which in the third world is often caused by poor ventilation and toxic cooking fuels, improved education and sanitation can help mitigate disease prevalence.

With genetically predisposed diseases like cystic fibrosis, however, the rise and spread of the disease is more common in certain ethnic groups, such as in people with northern European lineage. For this reason, the US has the largest population of CF patients, numbering between 30,000 and 40,000.

However, increasing globalization is contributing to a spread of genetic diseases like CF, leading to public health organizations in parts of the world previously unaffected by the disease to begin addressing best practices for researching, diagnosing, and treating CF.