UNICEF said that while these two diseases kill more than two million children each year, making up 29 percent of child deaths under age five worldwide, some simple interventions could save lots of lives in the coming years.
The report urges the 75 countries with the highest mortality rates to aim to treat poor children with diarrhoea and pneumonia the same way they do those from the top 20% of households, a so-called "equity approach".
Key interventions include vaccinating against the major causes of pneumonia and diarrhoea, encouraging infant breastfeeding, improving access to clean water and sanitation, offering antibiotics for pneumonia and rehydration solutions for diarrhoea.
Millions of lives could be saved
"Modeled estimates suggest that by 2015 more than two million child deaths due to pneumonia and diarrhoea could be averted across the 75 countries with the highest mortality burden," said the report.
"If national coverage of key pneumonia and diarrhoea interventions were raised to the level in the richest 20% of households in each country," it added.
About half of childhood deaths in the world due to diarrhoea or pneumonia take place in five countries: India, Nigeria, Democratic Republic of the Congo, Pakistan and Ethiopia, said the report.
There has been some progress in offering vaccines against Hemophilus influenza type b, as well as pneumococcal conjugate vaccines and rotavirus vaccines in the poorest countries, but more effort is needed, it said.
Water and sanitation is another key hurdle, with 783 million people globally not using an improved drinking water source, and 2.5 billion not using sanitation facilities.
"Nearly 90% of deaths due to diarrhoea worldwide have been attributed to unsafe water, inadequate sanitation and poor hygiene," said the report.
"Hand washing with water and soap, in particular, is among the most cost-effective health interventions to reduce the incidence of both childhood pneumonia and diarrhoea."
Pneumonia is responsible for 18% of childhood deaths worldwide each year, and diarrhoea is linked to 11%.
In contrast, Aids is responsible for 2% of global childhood deaths annually and malaria for 7%, according to the report.
(Sapa, June 2012)
Infant diarrhoea: Take action!