Forbes.com has an article on the 20 most earthquake vulnerable cities in the world, of which a large number belong to developing countries. GeoHazards International, a non-profit organization identified cities across the world that are at a higher risk of seismic calamities, by considering variables such as building frailty, emergency preparedness, potential for land slides and fires.
Of the 20 cities listed, Tokyo, Nagoya and Kobe are the only ones in a first-world nation, Japan. Kathmandu, Nepal tops the list with a possibility of 70,000 deaths if struck by an earthquake of 6 magnitude.

I have put together a Google Map of the cities and the number of deaths that may result as reported in the article.
Alternatively, you can click on the image to view the map