Burkholderia pseudomallei in Water Supplies, Southern Thailand

et al. Transfusion-transmitted hepatitis E in a misleading context of autoimmu-nity and drug-induced toxicity. Thermal inactivation of infectious hepatitis E virus in experimentally contaminated food. virus transmission from wild boar meat. Zoonotic transmission of hepatitis E virus from deer to human beings. demonstration of hepatitis E infection transmitted by pork meat ingestion. liver sausage as a source of hepatitis E virus transmission to humans. To the Editor: Melioidosis is an infectious disease caused by the environmental gram-negative bacillus Burkholderia pseudomallei, which is present in northern Australia and across much of Asia (1,2). In Thai-land, melioidosis is highly endemic to the northeast, where most infected persons are agricultural farmers with repeated environmental exposure (3). Melioidosis is infrequently reported from southern Thailand, although a cluster of 6 cases occurred in Phangn-ga Province after the December 2004 tsunami (4). Given the infrequency of reported cases, a cluster of 11 persons with melioidosis on Koh Phangan (an island in the Gulf of Thailand) during January–March 2012 (5) led to an investigation. Three case-patients were foreign tourists; 8 Thai case-patients were from 7 different villages throughout the island, and and none were agricultural workers (5). Three cases were fatal; water inhalation was suspected as a route of infection in a fatal case in a neonate who was born in a birthing pool outside of a hospital (online Technical Appendix Table 1, The lack of history for environmental exposure, such as farming, led to the hypothesis that water was the source of infection. After a request by Koh Phangan Hospital and the Thai Ministry of Public Health, an environmental survey was conducted for B. pseudo-mallei in water supplies on the island. In March 2012, we randomly collected water from accessible water supplies in local residences and hotels from all 14 villages on Koh Phangan. A total of 190 samples were collected (range 10–18 samples per village, Figure) for culture, genotyping, and analysis (online Technical Appendix). Isolates from 3 persons who died (a single bacterial colony saved from each person) from Koh Phangan were also available for genotyping and analysis. 26 (14%) of 190 samples were culture positive for B. pseudomallei. The pos-itivity rate did not differ by source of from local residences, hotels, and an ice cream shop, respectively. Positive water samples were distributed across the island (Figure). The median quantitative B. pseudomallei count was 30 CFU/L (range <10–11,300 CFU/L). The quantitative count did not differ …