Outbreak investigation of vitamin B1 deficiency in Si Sa Ket Provincial Prison, July 2023

Abstract

The objective of this descriptive epidemiological study was to verify the diagnosis, identify the causes and risk factors, and determine measures to treat and prevent vitamin B1 deficiency among 1,718 inmates in Si Sa Ket Provincial Prison during July 21-25, 2023. Data were collected from patients’ medical records, environmental observations, dietary behavior surveys, interviews using a form to investigate limb weakness developed specifically for Si Sa Ket Provincial Prison, laboratory tests, electrodiagnostic study, environments and consumption behaviors. Descriptive data analysis was conducted, which includes number, percentage, mean, standard deviation, minimum, and maximum. There were 84 male prisoners experiencing symptoms consistent with the case definition of vitamin B1 deficiency, representing the morbidity rate of 4.89% (84/1,718). Only 4 of the patients who met the case definition were confirmed cases and the rest were suspected cases. Signs and symptoms observed included muscle weakness (92.86%; 78/84), numbness (89.29%; 75/84), and myalgia (82.14%; 69/84). Abnormal examination results included gloss sensation (36.73%; 18/49), pinprick sensation (36.00%; 18/50), polyneuropathy (100%; 5/5), thiamine pyrophosphate below standard value (44.44%; 4/9), and thyroid function disorder (12.50%; 1/8). The risk behaviors that potentially caused vitamin B1 deficiency was that some inmates ate additional foods including instant noodles, fermented foods, processed foods, fish sauce, fermented fish, and canned foods. This outbreak was the first outbreak of dry beriberi in Si Sa Ket province with common sources. The main cause was unbalanced diet or lack of nutrition, together with Influenza B outbreak that was found only one week prior to the outbreak of vitamin B1 deficiency. For disease control measures: treat patients according to WHO treatment guidelines and administration of prophylactic vitamin B 1-6-12 for all prisoners, adjusting the nutrition intake by replacing the white rice with brown rice, consuming an appropriate amount of vitamin B1 by increasing protein from both meats and vegetables, and discontinuation of consumption of food that contains substances which destroy or inhibit the absorption of vitamin B1.