Thank you to everyone who took ONE’s pop quiz. On Monday, we asked readers to identify the leading cause of death for children under five – and the results were very interesting.

While it garnered just about 11 percent of votes, pneumonia is in fact the leading killer of children. Pneumonia is an infection of the lungs which is caused by many organisms, but globally, bacteria such as Hib and pneumococcus are estimated to cause more than half of all childhood pneumonia deaths. Every year, 2 million children under five years of age are killed by the disease (more than AIDS, malaria and measles combined), even though we have the tools we need to prevent and treat it, including immunizations and antibiotics.

On our quiz, the most popular choice with 59 percent of votes was diarrhea, the second leading cause of death for children under five. Below, in descending order, are the top causes of death for children under five and the accompanying percentage of votes each received:

1. Pneumonia (11%)
2. Diarrhea (59%)
3. Malaria (22%)
4. Measles (3%)
5. HIV/AIDS (6%)

If you found the results to be surprising, we thought you might. Despite its burden compared to other diseases, relatively little attention is given to pneumonia. ONE is part of the Global Coalition Against Pneumonia, a group of organizations that is trying to increase knowledge about the disease, and decrease the millions of avoidable childhood deaths. Together with fellow coalition members, ONE will observe the first-ever World Pneumonia Day on November 2nd. To learn more, visit www.worldpneumoniaday.org and continue to check out ONE’s blog for more posts about the disease.