Skip to Main Content


At 4:53 pm on Tuesday, January 12, 2010, an earthquake measuring 7.0 on the Richter scale hit Haiti. The earthquake was the most powerful to strike the island in more than 200 years, and it was centered near the capital city, Port-au-Prince, where a quarter of the nation’s nearly 10 million citizens lived.

The devastation caused by the earthquake was severe, with an estimated 250,000 residences and 30,000 commercial buildings either collapsed or severely damaged. The exact number of fatalities was uncertain, but the death toll was estimated to be 200,000 to 300,000, with another 300,000 nonfatal injuries. The number of displaced persons was estimated to be 1.3 million, with nearly 400,000 still residing in temporary shelters a year and a half after the earthquake.

The catastrophic dimensions of the earthquake can be attributed to a number of factors. Haiti is a very poor country, with 80% of its citizens living under the poverty level. As a consequence of the economic conditions, buildings there are poorly designed, constructed, and inspected. Construction materials are of inferior quality, and many buildings are sited on hillsides without adequate structural support. Moreover, the earthquake was centered in a densely populated area, increasing the number of people affected.

The tragedy of the earthquake was compounded by the logistical challenges of getting relief workers and supplies into the country. In addition, nearly two thirds of Haiti’s hospitals were destroyed by the earthquake, adversely impacting the speed and capacity of the medical response.

The devastation caused by the earthquake was followed 10 months later by an outbreak of cholera. This epidemic began in a region about 100 km north of Port-au-Prince, with the source presumed to be drinking water drawn from a contaminated river. Because three out of four Haitian households lack running water and sanitation conditions are poor, the disease was easily transmitted from person to person. Within 10 weeks, the disease had spread throughout the country, ultimately affecting 6% of all Haitians. Hundreds of thousands of persons were hospitalized, and more than 3000 deaths were reported within 2 months. New cases were still arising years after the outbreak, with peaks occurring during the rainy season and after hurricanes.

The earthquake and ensuing cholera epidemic in Haiti demonstrate dramatically that death and disability from natural disasters and communicable diseases still burden substantial human populations, particularly those in economically challenged parts of the world. In this chapter, we will examine general patterns of health and disease throughout the world, with a focus on variations across person, place, and time.


Imagine an effort to characterize the distribution and determinants of human health and disease around the world. Such an undertaking would require a large number of data sources; a highly collaborative, interdisciplinary team of investigators; extensive computational resources; complicated protocols ...

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.