6. ª×èÍàÃ×èͧ: |
EPIDEMIOLOGY OF ARABINOSE ASSIMILATION IN BURKHOLDERIA |
|
ª×èͼÙéÇÔ¨ÑÂ: |
Suwanna Trakulsomboon1,Varaporn Vuddhakul2,Prasit Tharavichitkul3,Narisorn Na- |
|
1Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, |
|
2Department of Microbiology, Faculty of Science, Prince of Songkla University, |
Songkhla, Thailand; 3Department of Microbiology, Faculty of Medicine, Chiang Mai |
University, Chiang Mai, Thailand; 4Faculty of Veterinary Medicine, Khon Kaen |
|
µÕ¾ÔÁ¾ì: Southeast Asian J. Trop Med Public Health. 1999. 30 (4): 756-759. |
Abstract. |
urkholderia pseudomallei is an environmental saprophyte that has been isolated widely |
from soil in Southeast Asia and the relationship between environmental contamination and |
clinical melioidosis has been established. It has been shown that the arabinose assimilation |
property of B.pseudomallei is probably one of the determinants indicating virulence of this |
organism. Therefore, the distribution of arabinose assimilation biotypes of B. pseudomallei |
collected from four geographic regions of Thailand was studied in order to determine an |
association between arabinose assimilation of B. pseudomallei and the uneven distribution of |
melioidosis found among these four areas. A total of 830 isolates of B.pseudomalle (412 patient |
isolates and 418 soil isolates) collected from the patients and soil in four regions of Thailand in |
1997 were tested for an ability to grow on a minimal agar medium supplemented with L- |
arabinose. All patient isolates except one could not utilise arabinose (Ara-). For 418 soil isolates, |
232 (55.5%) isolates were identified as Ara- type. They comprised 180 (62.5%), 36 (46.8%), 6 |
(35.3%) and 10 (27.8%) isolates derived from northeastern, southern, northern and central regions |
respectively. The ratios of Ara- to Ara+ were 1.7, 0.9, 0.5 and 0.4 among isolates collected from |
northeastern, southern, northern and central regions respectively. The prevalence of Ara- in soil |
isolates in northeast is significantly higher than those in other regions. This observation suggests |
that in addition to the presence of B. pseudomallei in soil which is one of the factors contributing |
to a burden of melioidosis in northeastern Thailand, the distribution of more virulent biotype |
(Ara-) soil isolates is a factor contributing to a high prevalence of melioidosis in northeastern |
Thailand as well. |