Pneumonia can be prevented with vaccines, and easily treated with antibiotics costing just 20 pence if properly diagnosed.
Despite this, it still kills more children under five than any other infectious disease.
Pneumonia claims the lives of over 800,000 children under the age of five each year.
It leaves an estimated 4.2 million children under the age of five in 124 low- and middle-income countries with critically low oxygen levels.
The situation threatens to become even more serious as a result of the disruptions to health services caused by the coronavirus pandemic.