“Burkholderia pseudomallei Causing Melioidosis: Research Challenges and Opportunities, 100 Years after its Discovery”
by: Dr. Natesan Vijayalakshmi
Senior Associate Professor, Department of Microbiology,
Faculty of Medicine, QIUP
DATE: 22 May 2013 (Wednesday)
TIME: 3 – 4 p.m
VENUE: Lecture Room 4, Applied Sciences Building, QIUP
It has been exactly a century since Whitmore and Krishnaswami (1912) first described Melioidosis in morphia addicts in Burma (Myanmar). The causative agent has been known from 1992 as the environmental gram negative saprophytic bacilli, Burkholderia pseudomallei. Melioidosis is endemic in Southeast Asia, particularly Thailand and Malaysia; and northern Australia. A retrospective analysis was carried out on 145 cases of Melioidosis extracted from the Melioidosis Registry set up and maintained since 2005 at the Clinical Research Centre, Alor Star, Kedah. The incidence of the disease was 16.35 per 100,000 per year with increased incidences during high rainfall. The major risk factors were diabetes (72% of all culture positive cases) and occupational activities. A high mortality rate of 33.8% (57% among diabetics) despite availability and susceptibility of B. pseudomallei to the recommended antibiotics, continues to be a cause for concern. Besides, a very high proportion of bacteremics (83%) among those who died with this infection indicates a very high level of exposure and load of bacteria. All in all a major health challenge presents, especially with the increasing number of reports of Melioidosis in areas outside the conventional endemic zones, the globally rapid increase in populations with diabetes (including in Malaysia), the alarmingly rapid geo-climatic changes occurring as well as the current very high cost of treatment (e.g. drug costings alone can range between RM 1,134 to 6,492 per case). Challenges such as these can only be met if there is a concerted trans-disciplinary approach towards carrying out the relevant research. What is required is a thorough understanding of the bacteria in terms of its presence in the environment and the impact of geo-climatic changes, coupled with studies at the molecular level pertaining to latency and reactivation in the body as well as on in-vivo drug resistance during treatment, the role of host immunological responses and glycaemic control in reducing mortality, particularly in infected diabetic individuals. If these challenges are not tackled now, it would raise a potential major health issue for future generations, especially as TB for example attacks more aggressively.