Leprosy cases have declined over the past two decades but much still needs to be done to help those suffering in silence because of the stigma, the World Health Organization (WHO) said on Monday.

Anarfi Asamoah-Baah, WHO assistant director-general for communicable diseases, said the number of countries in which leprosy had been a “major public health problem” decreased from 122 to 9 in the past 20 years.

He said 14 million people had been cured in the same period.

“They have been cured physically but they have not been cured emotionally and mentally because the bigger society has not been cured of the stigma of leprosy,” Asamoah-Baah, a Ghanaian, told a conference outside Johannesburg.

Many leprosy sufferers face being ostracized from their families and communities, who fear infection, which means that many are too ashamed to seek treatment.

Leprosy affects the skin and nerves, causing permanent damage if left untreated. It can incubate in the human body for up to 20 years.

The WHO says multidrug therapy has proved highly effective in fighting leprosy.

According to the global body, leprosy numbers have dropped from 804,000 in 1998 to 500,000 two years ago.

Brazil, India, Madagascar, Mozambique, Myanmar, and Nepal are the worst affected countries, accounting for 90 percent of the prevalence of the disease in the world in 2002. At the time India had 70 percent of this total.