In the JournalsPerspective

Melioidosis is a major neglected tropical disease, researchers argue

Melioidosis should be reconsidered as a major neglected tropical disease given its large global burden, which outmatches that of many other tropical diseases recognized as neglected, researchers argued in The Lancet Infectious Diseases.

“This systematic review and data synthesis is the first study to provide estimates of the global burden of melioidosis in terms of [disability-adjusted life years (DALYs)],” Emma Birnie, MD, a PhD candidate at the University of Amsterdam, and colleagues wrote.

The major endemic regions of melioidosis are Southeast Asia and northern Australia, though it appears to be ubiquitous across the tropics, Birnie and colleagues wrote. It is characterized by sepsis, abscess formation and a high case-fatality rate ranging between 10% to 50%, they noted.

According to the researchers, recognizing melioidosis as a neglected tropical disease could increase global focus on the illness and raise “much-needed” funding for research, surveillance and treatment.

Birnie and colleagues conducted a systematic review of peer-reviewed literature published from 1990 through 2015 on human melioidosis cases and extracted data on mortality, age, antibiotic treatment, symptom duration, sex and infectious and post-infectious sequelae. From these data, they explained, they created an incidence-based disease model and integrated it with established global incidence and mortality estimates to calculate global melioidosis DALYs.

The researchers estimated that the global burden of melioidosis in 2015 was 4.6 million DALYs (95% uncertainty interval [UI], 3.2-6.6), or 84.3 per 100,000 people (95% UI, 57.5-120). The most common outcomes were pneumonia, intra-abdominal abscess and sepsis.

Birnie and colleagues found that incidence, mortality and DALYs from melioidosis were approximately twice as high for men as for women, possibly due to differential occupational exposures, differential access to health care and genetic variation, they said.

“Countries with a high burden can address the issue by strengthening surveillance systems, preventive measures, and availability of minimal diagnostic facilities and antibiotic options,” Birnie and colleagues wrote. “Additionally, the contribution of risk factors and other factors of health utilization should allow more targeted population interventions and should lead to the official recognition of melioidosis as a major [neglected tropical disease.”

In a related editorial, Katherine B. Gibney, MPH, PhD, from the Royal Melbourne Hospital and University of Melbourne, and Allen C. Cheng, PhD, MPH, from Austin Hospital and Monash University, all in Melbourne, Australia, concluded that two findings warranted special mention.

“First, 99% of the DALY burden of melioidosis was attributed to deaths from melioidosis (years of life lost),” they wrote. “Second, a high DALY burden for melioidosis was estimated in countries with few or no reported melioidosis cases.” – by Joe Gramigna

Disclosures: The authors report no relevant financial disclosures.

Melioidosis should be reconsidered as a major neglected tropical disease given its large global burden, which outmatches that of many other tropical diseases recognized as neglected, researchers argued in The Lancet Infectious Diseases.

“This systematic review and data synthesis is the first study to provide estimates of the global burden of melioidosis in terms of [disability-adjusted life years (DALYs)],” Emma Birnie, MD, a PhD candidate at the University of Amsterdam, and colleagues wrote.

The major endemic regions of melioidosis are Southeast Asia and northern Australia, though it appears to be ubiquitous across the tropics, Birnie and colleagues wrote. It is characterized by sepsis, abscess formation and a high case-fatality rate ranging between 10% to 50%, they noted.

According to the researchers, recognizing melioidosis as a neglected tropical disease could increase global focus on the illness and raise “much-needed” funding for research, surveillance and treatment.

Birnie and colleagues conducted a systematic review of peer-reviewed literature published from 1990 through 2015 on human melioidosis cases and extracted data on mortality, age, antibiotic treatment, symptom duration, sex and infectious and post-infectious sequelae. From these data, they explained, they created an incidence-based disease model and integrated it with established global incidence and mortality estimates to calculate global melioidosis DALYs.

The researchers estimated that the global burden of melioidosis in 2015 was 4.6 million DALYs (95% uncertainty interval [UI], 3.2-6.6), or 84.3 per 100,000 people (95% UI, 57.5-120). The most common outcomes were pneumonia, intra-abdominal abscess and sepsis.

Birnie and colleagues found that incidence, mortality and DALYs from melioidosis were approximately twice as high for men as for women, possibly due to differential occupational exposures, differential access to health care and genetic variation, they said.

“Countries with a high burden can address the issue by strengthening surveillance systems, preventive measures, and availability of minimal diagnostic facilities and antibiotic options,” Birnie and colleagues wrote. “Additionally, the contribution of risk factors and other factors of health utilization should allow more targeted population interventions and should lead to the official recognition of melioidosis as a major [neglected tropical disease.”

In a related editorial, Katherine B. Gibney, MPH, PhD, from the Royal Melbourne Hospital and University of Melbourne, and Allen C. Cheng, PhD, MPH, from Austin Hospital and Monash University, all in Melbourne, Australia, concluded that two findings warranted special mention.

“First, 99% of the DALY burden of melioidosis was attributed to deaths from melioidosis (years of life lost),” they wrote. “Second, a high DALY burden for melioidosis was estimated in countries with few or no reported melioidosis cases.” – by Joe Gramigna

Disclosures: The authors report no relevant financial disclosures.

    Perspective
    Peter J. Hotez

    Peter J. Hotez

    Melioidosis is a serious bacterial neglected tropical disease caused by the gram-negative bacterium Burkholderia pseudomallei. Despite its importance as a tropical disease pathogen, especially in South Asia (Indian subcontinent) and Southeast Asia, it is not currently recognized as a neglected tropical disease pathogen by WHO, nor is it itemized as a separate disease burden estimate for the Global Burden of Disease Study. The paper by Birnie and colleagues in The Lancet Infectious Diseases assigns some important new disease burden estimates for melioidosis, including 4.6 million DALYs, a value exceeding many better known tropical infections, including dengue or tetanus, and an estimate roughly equivalent to the global disease burden of Hib meningitis. Moreover, years of life lost accounted for almost all of the DALYs, a finding consistent with the highly lethal nature of melioidosis. Data such as these provide an important advocacy tool to prioritize melioidosis for global health interventions, especially new drugs, diagnostics and vaccines for this disease.

    • Peter J. Hotez, MD, PhD
    • Dean, National School of Tropical Medicine
      Baylor College of Medicine
      Co-director, Center for Vaccine Development
      Texas Children’s Hospital ​ Disclosure: Hotez reports no relevant financial disclosures.

    Disclosures: Hotez reports no relevant financial disclosures.