Outbreak of beriberi in an Indian population of the upper Amazon region, Roraima State, Brazil, 2008.

Edema, parasthesias, and paresis affected 10 residents of an Indian community in Roraima state; three died. Mining with mercury occurs locally; caxirí, a traditional alcoholic drink, is consumed daily. We conducted a 1:2 unmatched case-control study; a case was an Indian from Uiramutã county (population of 9,127) who presented ≥ 1 of lower extremity edema, paresthesias, paresis, or weakness. Controls were asymptomatic Indians randomly selected from the population. We identified 90 cases (prevalence of 1%) and 180 controls; all were enrolled. Among cases, 79% were male, and the median age was 31 years. Ethnicity was Macuxí, and 49% had income. Cases had lower extremity edema (85%), upper extremity paresthesias (84%), and lower extremity weakness and pain (78%). Risk factors were male sex (odds ratio [OR] = 6.8; P < 0.001), age 31-40 years (OR = 5.63; P < 0.001), and consumption of caxirí (OR = 2.7; P < 0.003). Mercury exposure was not a risk. Thiamine therapy produced complete rapid clinical recovery in all cases, confirming the diagnosis of beriberi. We recommend surveillance, thiamine supplementation, and nutritional intervention.