This week, albinos and so-called witch doctors have made headlines. A number of news outlets reported that Tanzania had announced a ban on these "witch doctors" to curb attacks on people with albinism.

That made us wonder: What, exactly, is a witch doctor? And why are people with albinism under attack in Tanzania?

Roughly 1 in 1,400 Tanzanians has a rare genetic condition that results in the lack of pigment in his skin, hair or eyes. By comparison, the rate is 1 in 20,000 worldwide.

"People didn't know what albinism is," Grace Wabanhu, a Tanzanian with albinism, told NPR in 2012. "But after explaining to them they came to think, 'Hah, this is normal person like others.' "

Yet in Tanzania, the belief persists that people with albinism are "ghosts" and that their body parts harbor magical powers.That's why Tanzanian albinos — both adults and children — are the target of gruesome attacks and murders. Their arms, legs and even genitals are hacked off and traded for use in potions for good luck. A typical client will pay up to $4,000 in U.S. dollars for a limb and between $75,000 and $100,000 for an entire set of organs.

The culprits are those who practice magic with body parts, like fortunetellers and soothsayers.

In a bid to halt the attacks, Tanzania announced this week that the government will set up a special task force to arrest and convict "those who cheat people [telling them] that they will be rich by possessing charms, as well as fortunetellers and those distributing talismans," Home Affairs Minister Mathias Chikawe said, according to Agence France-Presse.

Traditional healers who work with herbal remedies are not being targeted, AFP adds.

Which brings us back to the question: What is a witch doctor?

The term is a broad, misleading — and somewhat condescending — way to refer to traditional healers in Africa. The label did not originate from the Swahili language, says Dr. Stacey Langwick, a medical anthropologist at Cornell University, who has studied traditional healing in Tanzania. "Colonialism introduced this term witchcraft as a legal category based on concepts of witchcraft in Europe," she says. "Witchcraft tends to be understood colloquially as the use of medicine to harm rather than to heal, but even today it has very complicated connotations in everyday and formal political speech."

She says traditional healers in Tanzania, many of whom are licensed by the government, have long been tied to relationships with ancestors and other spirits. For example, healers often say their ancestors appear in dreams to tell them about herbal medicines. The vast majority of traditional healers, she adds, do not condone using body parts and would not harm anyone to obtain elements for a remedy.

Tanzania's new ban comes just days after a U.N. official demanded that the government find a 4-year-old girl with albinism who was kidnapped last month. It's a move welcomed by the country's main advocacy organization for albinos, the Tanzanian Albinism Society. Severin Edward, a representative of the society, told The Telegraph that the new ban is a "good start" and that he hopes it will lead to "tangible" action.

Peter Ash isn't as optimistic. Ash, who himself has albinism, runs the Canada-based charity Under the Same Sun, which advocates for Tanzanians with albinism. The problem, he says, is the lack of enforcement.

Since 2006, his nonprofit has recorded more than 152 attacks and killings inside and outside Tanzania. Only about 5 percent of those cases have been taken to court. Ash suspects that hundreds more go unreported.

Part of the problem, he says, is that the individuals who use albino body parts do their business underground and in the dead of night. Another problem is that their customers, who include politicians seeking re-election and businessmen looking for a magic way to gain wealth, are almost never prosecuted. The few practitioners who were arrested have been reluctant to rat them out.

"[The new ban] stops a small group of people called fortunetellers and soothsayers who are not regulated by the government, but even then, it's only the ones that [officials] have reason to believe are involved in albino killings," Ash says.

Often the clients themselves carry out the attacks. Sometimes killers are hired by the "witches" — as Isaac Nantanga, spokesperson for Tanzania's Interior Ministry, called them in the AFP report.

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