Albinism is a rare, non-contagious, genetically inherited condition which occurs worldwide regardless of ethnicity or gender. It most commonly results in the lack of melanin pigment in the hair, skin and eyes (oculocutaneous albinism), causing vulnerability to sun exposure. This can lead to skin cancer and severe visual impairment. Both parents must carry the gene for it to be passed on to their children, even if they do not themselves have manifestations of the condition.
The prevalence of albinism varies across the world. According to the World Health Organization, estimates vary from 1 in 5,000 to 1 in 15,000 people in Sub-Saharan Africa. In Europe and North America, 1 in 20,000 people have the condition according to the NGO Under the Same Sun. However, data on the prevalence of albinism by country remains scarce.
The term “person with albinism” is preferred to “albino”, which is often used in a derogatory way.
Three men armed with machetes killed an 8-year-old albino boy in Burundi last week and are believed to have smuggled his limbs to Tanzania, where witch doctors use albino body parts for potions. At least 35 albinos were killed in Tanzania in 2008, prompting police officials to set up an emergency hot line and a program to distribute free cell phones to all albinos. How many albinos are there in
Tanzania?
A whole lot. Albinism, a genetic disorder characterized by lack of melanin pigment in the skin, hair, and eyes, is listed as a rare disease by the National Institutes of Health—meaning it affects fewer than 200,000 Americans. Around the world, between one in 17,000 and one in 20,000 people are albinos. The prevalence in parts of Africa, however, is far higher than the global average. Albinos make up about one in 4,000 people in South Africa and perhaps one in 5,000 in Nigeria. According to a 2006 review published in the journal BMC Public Health, the prevalence in Tanzania is one in 1,400, but this estimate is based on incomplete data.
Since Tanzania’s total population is more than 40 million, that would suggest an albino community of about 30,000. A census is under way, however, and the Albino Association of Tanzania believes the total figure could be more than 150,000.
Albinism may be more prevalent in some geographic areas because of inbreeding. A study published in 1982 notes that albinism is less common among the South African Zulu and Xhosa tribes (one in 4,500) than the Swazi and Sotho-Tswana tribes (one in 2,000), which have no taboo against cousins marrying. In Zimbabwe, about four-fifths of albinos belong to the majority ethnic group, the Shona. Since the Shona discourage consanguineous relationships, this prevalence may be the result of the founder effect, wherein a small number of people from a larger population form a new community, resulting in the loss of genetic variation. But the extraordinary rate of albinism in Tanzania is not yet fully understood.
In any case, albinism is especially dangerous in sunny climates, like Tanzania’s, because lack of melanin predisposes albinos to severe skin damage from UV exposure. Albinos frequently suffer from sunburns, blisters, and solar keratosis as well as visual problems like myopia.
Bonus Explainer: How do you count albinos? Look to the children. Researchers distribute surveys at schools and conduct interviews with administrators to get a sense of the albino population among the pupils, then extrapolate to the rest of the population.
Hospital maternity wards are sometimes targeted, too, to count the number of albino babies born. And Albino Associations conduct outreach programs to register the local population officially.