White South Africans are not known for their belief in spirits and magic, which are usually part of the faith system of the country's blacks. But growing numbers of them are crossing the cultural divide and studying with black healers in a bold attempt to integrate two opposite world views.

When Valerie Harvey was an 11-year-old in mid-1960s Johannesburg, strange things began happening to her.

"I dreamed of a bird I had never seen before. I heard voices, as if two men were talking to me. I had stomach and joint pains that doctors could not explain."

Many black South Africans would interpret Harvey's experiences as "thwasa illness" - an alleged sign from one's ancestors that one is being called upon to become a traditional healer.

But Harvey was a white girl living under the apartheid regime, which stipulated that she was not to have any contact with black culture.

The symptoms returned when Valerie was 19.

"A woman working at a shop selling esoteric products advised me to see a sangoma" - the word traditional healers are best known by.

For most white South Africans - about 8.5 per cent of the 53-million population - entering the world of African traditional healing would be a culture shock.

Many traditional healers not only administer herbal medicines. They also sacrifice animals to spirits; go into trances in order to allow ancestral spirits to speak through them; and perform magical rituals.

Their concept of healing is very different from that of Western medicine, which stresses scientific diagnoses and treats the body separately from the mind.

Harvey nevertheless took the plunge.

"My mother had been open to African traditions and I have always felt more comfortable with black people" than white, the 62-year-old says.

She admits that she did experience "internal conflict" between the new world she was entering and her Catholic background.

Harvey trained for nearly a decade, spending time with three healers separately. Her teachers came from different ethnic groups - the Swazi, the Zulu and the Shangani.

They taught her about their beliefs in the existence of spirits; to heal with herbs; to read an oracle consisting of bones and other objects that are thrown on the floor and whose positions are then interpreted; and to "read signs in nature."

Harvey finally underwent an initiation lasting several days during which she fasted, ingested a hallucinogenic plant, inhaled steam from plants, purged and endured cuts to her skin into which herbs were inserted.

She today attends to her clients mainly by reading cards to see into the future. But other white healers make use of traditionally African methods, including sacrificing goats and drinking their blood, according to media reports.

There is a growing phenomenon of whites becoming traditional healers in South Africa, Annette Wozniak wrote in a 2009 research report for Witwatersrand University.

It is not known how many among South Africa's estimated 200,000 traditional healers are white. Traditional health care expert, professor Nceba Gqaleni from the University of KwaZulu-Natal, estimates that they may number several hundred.

About 80 per cent of South Africans rely on traditional healers for their primary health care needs, both physical and psychological, according to Gqaleni and other experts.

Post-apartheid South Africa stopped branding traditional medicine primitive or evil, with a 2007 law recognizing it as legitimate.

A council of experts is now due to start checking the qualifications of traditional healers and registering them, according to Gqaleni, who is a member in the council.

Traditional healers have also started being given training about hygiene and illnesses such as AIDS. Some South African employers accept sickness leave certificates issued by them. They also increasingly cooperate with Western-trained doctors, Gqaleni said.

Healers may refer patients suffering from severe physical diseases to doctors, while doctors send healers patients whose symptoms appear to be psychosomatic.

The growing acceptance of traditional medicine is facilitating the entry of white people into the trade.

Some of them even combine the professions of sangoma and clinical psychologist, according to Wozniak, who interviewed several such people. They appeared to experience "some degree of tension, contradiction or conflict" in holding a "dual identity," she reported.

Harvey says she reconciled the two cultures by identifying ancestral spirits with angels and saints.

"Some black people might not trust a white sangoma," Gqaleni says, but Harvey reports that most of her clients are black.

Some representatives of traditional healers have publicly said whites do not qualify, because they have no African ancestors familiar with a local healing tradition to reveal their calling. David Shilaluke, a black sangoma based in Orange Farm near Johannesburg, disagrees.

Traditional medicine has been practised in Europe as well, and a white as well as a black person "may have had an ancestor who worked with herbs," he said.

"We cannot refuse to share knowledge with some people just because they are white," said Norman Nkambule, another traditional healer. "We live in a globalized world."