The deadly earthquake that struck on April 25 killed thousands of people and made many more homeless.

One non-government organisation working to prevent child trafficking said it had seen an increase in suspicious cases at the porous border with India which has in the past been used to traffic women and children from Nepal into slavery and prostitution.

"Girls are at high risk of trafficking and sexual abuse, they have to be protected," Anuradha Koirala, the founder of Maiti Nepal, an anti-trafficking organisation, told AFP.

Koirala said her organisation had increased its monitoring operations on the border with India.

A cycle of unemployment, poverty, gender discrimination and impact of 10-year Maoist insurgency has made Nepalese women and children in the country easy targets for traffickers.

A 2013 report by the country's human rights commission recorded 29,000 incidences of trafficking or attempted trafficking in the country.

"We have special teams inspecting camps and shelters to ensure that women and children live in a safe environment," said deputy spokesman for Nepal Police, Sarbendra Khanal.

"We understand that there is a threat, and we are working to put in preventive measures."

Relief agencies working in quake-hit areas are seeking to raise awareness of the dangers to vulnerable people.

But Kamal Thapa Chettri from the trafficking office at Nepal's Human Rights Commission said agents could also be posing as aid workers.

"This (quake) gives them an opportunity to see who is desperate and find potential targets. The quake-hit areas definitely face an increased risk," he said.

Health workers race to prevent Nepal measles outbreak
Kotdanda, Nepal (AFP) May 6, 2015 - Health workers are rushing to vaccinate more than half a million children in Nepal as fears grow that last month's massive earthquake has made youngsters more susceptible to disease.

UNICEF has warned of a race against time to prevent a deadly outbreak of measles in the impoverished Himalayan nation following the April 25 quake that killed 7,652 people in Nepal.

The UN children's fund, the World Health Organization and the Nepalese government are targeting the urgent inoculation of 500,000 children in the areas worst-hit by the quake.

"Before the earthquake, one in ten children in Nepal was not vaccinated against measles, so we're going to vaccinate half a million children in the coming weeks," Kent Page, UNICEF Nepal's emergency spokesperson, told AFP.

At a mobile vaccination unit Wednesday in mountainous Kotdanda, near the capital Kathmandu, a steady stream of women queued up, each carrying a baby or young child. The children received a medical checkup by female Nepali health workers before receiving their vaccinations.

"Many of the children are living outdoors, they're not getting the food they need, their sort of physical well-being isn't so good, so they're more susceptible to often fatal diseases like measles," Page said.

"We're doing this measles vaccination campaign to prevent any outbreak or spread of measles," he added.

Health workers have started by immunising children under five in makeshift camps that have sprung up in three densely-populated districts in Kathmandu Valley -- Bhaktapur, Kathmandu and Lalitpur.

The vaccination drive will eventually include 12 districts most affected by the disaster.