Kathmandu, Nepal - The 1,758-kilometre (1,092-mile) border between Nepal and India has always been known as one of the busiest human trafficking gateways in the world.

Since a 2015 earthquake in Nepal - which killed nearly 9,000 people, severely disrupted social and economic structures, and sank scores into destitution - the numbers have risen sharply, with thousands of Nepalese being trafficked across the border and vanishing, never to return.

Nepalese victims are plunged into the world of human trafficking in different ways. Some hoped to find jobs as domestic workers in India or Gulf countries but ended up being trafficked and raped in brothels abroad. Others were simply whisked away from their families and sold to brothels in India.

Many others fall prey to another type of human trafficking: illegal organ harvesting in India.

Research suggests that "approximately 12,000 children are trafficked by strangers, neighbours and families to India every year mainly for sexual exploitation" but also for work in fisheries, construction, circuses, domestic work, sweatshops, among many other forms of forced labour and exploitation, also including organ removal.

Many trafficking victims never even cross the border; the danger is present at home as well.

Women and girls from rural areas are promised work and trafficked to urban centres within Nepal. Instead, they end up forced into prostitution in one of the hundreds of singing restaurants, dance bars or massage parlours that function as fronts for brothels in Kathmandu. It is estimated that 11,000 to 13,000 girls and women work there, most of them underage.

Nepal's civil society is trying to fight back. Every day, border monitors, some of whom are trafficking survivors themselves, try to intercept and rescue potential victims at border posts, preventing them from being trafficked out of Nepal. Others raise their voices against the deep social stigma that pursues its victims at home.

Human trafficking is a thriving business. It accounts for $150bn a year worldwide, with women and girls making up 71 percent of all modern slavery victims. Nepal is one of the most lucrative markets. From there alone, at least 54 girls and women are trafficked into India every day.

The UN's International Labour Organization has warned that there are more than 40 million enslaved people worldwide - more than at any time in history. Nepal accounts for only a fraction of the underground market in human beings, and the toll it takes.

*Note: Not their real name

Violeta Santos Moura's work in Nepal was supported by the Kim Wall Memorial Fund through the International Women's Media Foundation (IWMF).