In the 2000s, there were outbreaks in countries such as Angola, Zimbabwe and Nepal. In Angola specifically, recent reports show a similar incidence of pellagra since 2002, with clinical pellagra in 0.3% of women and 0.2% of children and niacin deficiency in 29.4% of women and 6% of children related to high untreated corn consumption.In other countries such as the Netherlands and Denmark, even with sufficient intake of niacin, cases have been reported. In this case, deficiency might happen not just because of poverty or malnutrition but secondary to alcoholism, drug interaction (psychotropic, cytostatic, tuberculostatic or analgesics), HIV, vitamin B2 and B6 deficiency, or malabsorption syndromes such as Hartnup disease and carcinoid tumors. History
Native American cultivators who first domesticated corn (maize) prepared it by nixtamalization, in which the grain is treated with a solution of alkali such as lime. Nixtamalization makes the niacin nutritionally available and prevents pellagra. When maize was cultivated worldwide, and eaten as a staple without nixtamalization, pellagra became common. Pellagra was first described for its dermatological effect in Spain in 1735 by Gaspar Casal. He explained that the disease causes dermatitis in exposed skin areas such as hands, feet and neck and that the origin of the disease is poor diet and atmospheric influences. His work published in 1762 by his friend Juan Sevillano was titled Historia Natural y Medicina del Principado de Asturias or Natural and Medical History of the Principality of Asturias (1762).
Between 1906 and 1940 more than 3 million Americans were affected by pellagra with more than 100,000 deaths, yet the epidemic resolved itself right after dietary niacin fortification. Pellagra deaths in South Carolina numbered 1,306 during the first ten months of 1915; 100,000 Southerners were affected in 1916. At this time, the scientific community held that pellagra was probably caused by a germ or some unknown toxin in corn. The Spartanburg Pellagra Hospital in Spartanburg, South Carolina, was the nations first facility dedicated to discovering the cause of pellagra. It was established in 1914 with a special Congressional appropriation to the U.S. Public Health Service (PHS) and set up primarily for research. In 1915, Dr. Joseph Goldberger, assigned to study pellagra by the Surgeon General of the United States, showed it was linked to diet by observing the outbreaks of pellagra in orphanages and mental hospitals. Goldberger noted that children between the ages of 6 and 12 (but not older or younger children at the orphanages) and patients at the mental hospitals (but not doctors or nurses) were the ones who seemed most susceptible to pellagra. Goldberger theorized that a lack of meat, milk, eggs, and legumes made those particular populations susceptible to pellagra. By modifying the diet served in these institutions with "a marked increase in the fresh animal and the leguminous protein foods," Goldberger was able to show that pellagra could be prevented. By 1926, Goldberger established that a diet that included these foods, or a small amount of brewers yeast, prevented pellagra.