A powerful earthquake measuring 7.8-magnitude struck an area between the capital, Kathmandu, and the city of Pokhara, around midday on Saturday, collapsing buildings and homes, toppling centuries-old cultural monuments, severely cracking roads and damaging communications infrastructure.
"The standard of housing construction in Nepal is extremely low, which is why the damage to buildings has been extremely severe," Biswas noted.
As a poverty-stricken nation, Nepal's capacity to fund disaster relief and long-term reconstruction efforts is extremely limited, said Biswas.
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Nepal's per capita GDP stood at $694 in 2013, according to the World Bank, compared with $1,497 in neighboring India and $ 6,807 in China.
"A coordinated international disaster relief and long-term reconstruction program will need to be funded by bilateral assistance from donor nations and development financing agencies under the coordinated management of multilateral institutions such as the United Nations," he said.
Governments and aid agencies are rushing search-and-rescue and disaster relief personnel to Kathmandu, with India, China, Pakistan and the U.S. leading international efforts.
However, rescue work has been hampered by a series of aftershocks and adverse weather conditions.
Widespread damage to road networks, which has essentially cut off access to rural areas, is also presenting a grave challenge for aid workers.
"[Our personnel] are driving as far as they can and they are going the rest of the way by foot, its taking sometimes up to 6, 7, 8 hours for some of our teams to get to the areas that they want to assess," Mark Smith, senior director, Emergency Affairs at World Vision told CNBC.
"We're starting to get some preliminary reports but it's going to take 2-3 days before a lot of aid is going to get mobilized into these rural areas because of the access issues," he said.
While Kathmandu's airport opened on Sunday, some aid flights were prevented from landing by aftershocks, according to Reuters.
Sanjay Karki, country director at Mercy Corps, who is on the ground in Kathmandu, highlighted the pressing need for medical assistance.
"Hospitals have been overflooded. When you enter hospitals, you can see all the patients lying in open spaces. There will be a shortage of medicine soon," he said.
The country has just 2.1 physicians and 50 hospital beds for every 10,000 people, according to the World Health Organization.
"There have been blood donation camps organized by communities in the neighborhood, but that will run out," he added.