KATHMANDU, April 30 -- Around 1.7 million children are now in urgent need of aid in the worst-hit areas by the massive earthquake in Nepal, according to UNICEF.

UNICEF revealed the figure as it launched a 50.35 million U.S. dollars appeal to get humanitarian assistance to children and their families amid growing risk of disease outbreaks.

The 7.9 magnitude earthquake has killed more than 5000 people and injured more than 10,000. It has also driven tens of thousands of people into open spaces and temporary camps in the Kathmandu valley and the rest of the worst-affected districts.

"The lives of so many children have been torn apart and they are in desperate need of life-saving support, including clean water, shelter and sanitation," said Tomoo Hozumi, UNICEF Nepal Representative.

"Without safe water supply, waterborne diseases remain huge risks for children. Many families are struggling simply to protect themselves from the sun and rain and we only expect needs to grow in the coming days as we receive more information from remote areas and the full scale of the disaster becomes more apparent," Hozumi added.

More than 80 percent of health facilities in the five most severely affected districts have been extensively damaged.