Seroprevalence of Burkholderia pseudomallei in East Timorese refugees: implications for healthcare in East Timor.

Abstract

Melioidosis is a disease with protean clinical manifestations caused by the bacterium Burkholderia pseudomallei. It is endemic in countries surrounding the newly independent East Timor, but has yet to be isolated or demonstrated serologically in that country. One illness that can be clinically indistinguishable from melioidosis is pulmonary tuberculosis, a condition with a very high prevalence in East Timor. We used an indirect hemagglutination test (IHA) to measure antibodies to B. pseudomallei in 407 East Timorese evacuated to Darwin, Australia, in September 1999. Assuming a positive IHA titer as ≥1:40, the overall seroprevalence rate was 17.0%, in keeping with other seroprevalence studies from the region. The IHA titres ranged up to 1:320. After adjusting for age, females were 2.5 times more likely to be seropositive than males (p=0.0001). There was an inverse relationship between seropositivity and age. This study shows that exposure to B. pseudomallei occurs in East Timor melioidosis is also likely to occur. Due to the lack of laboratory facilities at present, it may be some time before a laboratory-confirmed case proves that melioidosis occurs. In the meantime, clinicians in East Timor should include melioidosis in the differential diagnosis of the many conditions that it may mimic.