San Pablo was constructed in 1925, next to the Amazon river and about 100 km away from Iquitos. In the mid to late 1920s it held at least 50 patients a year. In 1935 it housed 150, in 50 ramshackle huts.

In 1941, under the direction of Dr M Kuczynski, San Pablo became an "agricultural" colony, in which patients had to cultivate goods for themselves and for sale. It continued to grow and, in 1943, 295 patients were admitted. According to reports from the 1950s, the majority of inhabitants there were male, and mestizo or Indian.

Life and conditions in the colony both before and after Kuczynski's arrival were described by an anonymous female resident, who later became his assistant, in Vida de Leprosa. Lima: La Reforma Medica, 1947.

Source: Marcos Cueto, "Social Medicine and 'Leprosy'", The Americas, 61.1 (2004): 55-80.