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Modelling population dynamics and seasonal movement to assess and predict the burden of melioidosis.PLoS Neglected Tropical Diseases May 2019Melioidosis is an infectious disease that is transmitted mainly through contact with contaminated soil or water, and exhibits marked seasonality in most settings,...
BACKGROUND
Melioidosis is an infectious disease that is transmitted mainly through contact with contaminated soil or water, and exhibits marked seasonality in most settings, including Southeast Asia. In this study, we used mathematical modelling to examine the impacts of such demographic changes on melioidosis incidence, and to predict the disease burden in a developing country such as Thailand.
METHODOLOGY/PRINCIPAL FINDINGS
A melioidosis infection model was constructed which included demographic data, diabetes mellitus (DM) prevalence, and melioidosis disease processes. The model was fitted to reported melioidosis incidence in Thailand by age, sex, and geographical area, between 2008 and 2015, using a Bayesian Markov Chain Monte Carlo (MCMC) approach. The model was then used to predict the disease burden and future trends of melioidosis incidence in Thailand. Our model predicted two-fold higher incidence rates of melioidosis compared with national surveillance data from 2015. The estimated incidence rates among males were two-fold greater than those in females. Furthermore, the melioidosis incidence rates in the Northeast region population, and among the transient population, were more than double compared to the non-Northeast region population. The highest incidence rates occurred in males aged 45-59 years old for all regions. The average incidence rate of melioidosis between 2005 and 2035 was predicted to be 11.42 to 12.78 per 100,000 population per year, with a slightly increasing trend. Overall, it was estimated that about half of all cases of melioidosis were symptomatic. In addition, the model suggested a greater susceptibility to melioidosis in diabetic compared with non-diabetic individuals.
CONCLUSIONS/SIGNIFICANCE
The increasing trend of melioidosis incidence rates was significantly higher among working-age Northeast and transient populations, males aged ≥45 years old, and diabetic individuals. Targeted intervention strategies, such as health education and awareness raising initiatives, should be implemented on high-risk groups, such as those living in the Northeast region, and the seasonally transient population.
Topics: Aged; Burkholderia pseudomallei; Female; Humans; Incidence; Male; Melioidosis; Middle Aged; Population Dynamics; Seasons; Thailand
PubMed: 31071094
DOI: 10.1371/journal.pntd.0007380 -
Emerging Infectious Diseases Feb 2015Melioidosis is a severe disease that can be difficult to diagnose because of its diverse clinical manifestations and a lack of adequate diagnostic capabilities for...
Melioidosis is a severe disease that can be difficult to diagnose because of its diverse clinical manifestations and a lack of adequate diagnostic capabilities for suspected cases. There is broad interest in improving detection and diagnosis of this disease not only in melioidosis-endemic regions but also outside these regions because melioidosis may be underreported and poses a potential bioterrorism challenge for public health authorities. Therefore, a workshop of academic, government, and private sector personnel from around the world was convened to discuss the current state of melioidosis diagnostics, diagnostic needs, and future directions.
Topics: Humans; Melioidosis; Practice Guidelines as Topic
PubMed: 25626057
DOI: 10.3201/eid2102.141045 -
Emerging Infectious Diseases May 2015
Review
Topics: Adolescent; Burkholderia pseudomallei; Humans; Male; Melioidosis; Treatment Outcome; Trinidad and Tobago
PubMed: 25897877
DOI: 10.3201/eid2105.141610 -
Applied and Environmental Microbiology Jun 2022Burkholderia pseudomallei is a Gram-negative soil saprophyte with the potential to cause melioidosis, an opportunistic disease with a high mortality potential. Periodic...
Burkholderia pseudomallei is a Gram-negative soil saprophyte with the potential to cause melioidosis, an opportunistic disease with a high mortality potential. Periodic case reports of melioidosis in or imported from Africa occur in the literature dating back decades. Furthermore, statistical models suggest Western sub-Saharan Africa as a high-risk zone for the presence of B. pseudomallei. A recent case report from the United Kingdom of a returning traveler from Ghana highlights the need for environmental studies in Ghana. We examined 100 soil samples from a rice farm in south-central Ghana. Soil was subjected to selective enrichment culture for B. pseudomallei using threonine-basal salt solution with colistin (TBSS-C50) and erythritol medium, as described in the literature. Bacterial cultures were identified with standard biochemical tests, a rapid antigen detection assay, and real-time PCR specific for B. pseudomallei. Of the 100 soil samples, 55% yielded cultures consistent with B. pseudomallei on Ashdown's agar as well as by capsular polysaccharide antigen production. This is the first confirmatory report of culture-confirmed B. pseudomallei in the environment of Ghana. Our study emphasizes the need for further exploration of the burden of human melioidosis in Ghana. We recommend that local clinicians familiarize themselves with the diagnosis and clinical management of melioidosis, while laboratories develop capacity for the safe isolation and identification of B. pseudomallei. We present the first confirmation of the presence of B. pseudomallei in the environment of Ghana. This study will bring attention to a disease with the potential to cause significant morbidity and mortality in Ghana, but which has gone completely unrecognized until this point. Furthermore, this work would encourage local clinicians to familiarize themselves with the diagnosis and clinical management of melioidosis and laboratories to develop capacity for the safe isolation and identification of B. pseudomallei.
Topics: Burkholderia pseudomallei; Ghana; Humans; Melioidosis; Soil; Soil Microbiology
PubMed: 35652663
DOI: 10.1128/aem.00600-22 -
Clinical Microbiology Reviews Apr 2005Melioidosis, caused by the gram-negative saprophyte Burkholderia pseudomallei, is a disease of public health importance in southeast Asia and northern Australia that is... (Review)
Review
Melioidosis, caused by the gram-negative saprophyte Burkholderia pseudomallei, is a disease of public health importance in southeast Asia and northern Australia that is associated with high case-fatality rates in animals and humans. It has the potential for epidemic spread to areas where it is not endemic, and sporadic case reports elsewhere in the world suggest that as-yet-unrecognized foci of infection may exist. Environmental determinants of this infection, apart from a close association with rainfall, are yet to be elucidated. The sequencing of the genome of a strain of B. pseudomallei has recently been completed and will help in the further identification of virulence factors. The presence of specific risk factors for infection, such as diabetes, suggests that functional neutrophil defects are important in the pathogenesis of melioidosis; other studies have defined virulence factors (including a type III secretion system) that allow evasion of killing mechanisms by phagocytes. There is a possible role for cell-mediated immunity, but repeated environmental exposure does not elicit protective humoral or cellular immunity. A vaccine is under development, but economic constraints may make vaccination an unrealistic option for many regions of endemicity. Disease manifestations are protean, and no inexpensive, practical, and accurate rapid diagnostic tests are commercially available; diagnosis relies on culture of the organism. Despite the introduction of ceftazidime- and carbapenem-based intravenous treatments, melioidosis is still associated with a significant mortality attributable to severe sepsis and its complications. A long course of oral eradication therapy is required to prevent relapse. Studies exploring the role of preventative measures, earlier clinical identification, and better management of severe sepsis are required to reduce the burden of this disease.
Topics: Animals; Anti-Bacterial Agents; Burkholderia pseudomallei; Humans; Melioidosis
PubMed: 15831829
DOI: 10.1128/CMR.18.2.383-416.2005 -
The American Journal of Tropical... Jan 2022Melioidosis is a tropical infectious disease caused by the soil-dwelling bacterium Burkholderia pseudomallei with a mortality of up to 50% in low resource settings. Only...
Melioidosis is a tropical infectious disease caused by the soil-dwelling bacterium Burkholderia pseudomallei with a mortality of up to 50% in low resource settings. Only a few cases have been reported from African countries. However, studies on the global burden of melioidosis showed that Africa holds a significant unrecognized disease burden, with Nigeria being at the top of the list. The first World Health Organization African Melioidosis Workshop was organized in Lagos, Nigeria, with representatives of health authorities, microbiology laboratories, and clinical centers from across the continent. Dedicated hands-on training was given on laboratory diagnostics of B. pseudomallei. This report summarises the meeting objectives, including raising awareness of melioidosis and building capacity for the detection, diagnosis, biosafety, treatment, and prevention across Africa. Further, collaboration with regional and international experts provided a platform for sharing ideas on best practices.
Topics: Africa; Burkholderia pseudomallei; Capacity Building; Congresses as Topic; Humans; Melioidosis; Nigeria; World Health Organization
PubMed: 35008053
DOI: 10.4269/ajtmh.21-0673 -
PLoS Neglected Tropical Diseases Jun 2017Melioidosis is a life threatening infectious disease caused by the gram-negative bacillus Burkholderia pseudomallei predominantly found in southeast Asia and northern...
BACKGROUND
Melioidosis is a life threatening infectious disease caused by the gram-negative bacillus Burkholderia pseudomallei predominantly found in southeast Asia and northern Australia. Studying the host transcription profiles in response to infection is crucial for understanding disease pathogenesis and correlates of disease severity, which may help improve therapeutic intervention and survival. The aim of this study was to analyze gene expression levels of human host factors in melioidosis patients and establish useful correlation with disease biomarkers, compared to healthy individuals and patients with sepsis caused by other pathogens.
METHODS
The study population consisted of 30 melioidosis cases, 10 healthy controls and 10 sepsis cases caused by other pathogens. Total RNA was extracted from peripheral blood mononuclear cells (PBMC's) of study subjects. Gene expression profiles of 25 gene targets including 19 immune response genes and 6 epigenetic factors were analyzed by real time quantitative polymerase chain reaction (RT-qPCR).
PRINCIPAL FINDINGS
Inflammatory response genes; TLR4, late onset inflammatory mediator HMGB1, genes associated with antigen presentation; MICB, PSMB2, PSMB8, PSME2, epigenetic regulators; DNMT3B, HDAC1, HDAC2 were significantly down regulated, whereas the anti-inflammatory gene; IL4 was up regulated in melioidosis patients compared to sepsis cases caused by other pathogens. Septicaemic melioidosis cases showed significant down regulation of IL8 compared to sepsis cases caused by other pathogens. HMGB1, MICB, PSMB8, PSMB2, PSME2, HDAC1, HDAC2 and DNMT3B showed consistent down regulation of gene expression in melioidosis patients compared to other sepsis infection, irrespective of comorbidities such as diabetes, duration of clinical symptoms and antibiotic treatment.
SIGNIFICANCE
Specific immune response genes and epigenetic regulators are differentially expressed among melioidosis patients and patients with sepsis caused by other pathogens. Therefore, these genes may serve as biomarkers for disease diagnosis to distinguish melioidosis from cases of sepsis due to other infections and therapeutic intervention for melioidosis.
Topics: Biomarkers; Diagnosis, Differential; Gene Expression Profiling; Genes, Regulator; Humans; Immunologic Factors; Melioidosis; Real-Time Polymerase Chain Reaction; Sri Lanka
PubMed: 28628607
DOI: 10.1371/journal.pntd.0005643 -
The Cochrane Database of Systematic... 2001Melioidosis is an infectious disease caused by a bacterium (Burkholderia pseudomallei) found particularly in some areas in the tropics. It is a serious condition which... (Review)
Review
BACKGROUND
Melioidosis is an infectious disease caused by a bacterium (Burkholderia pseudomallei) found particularly in some areas in the tropics. It is a serious condition which can be fatal. Beta lactam antibiotics have dramatically reduced the risk of death, but mortality still remains high.
OBJECTIVES
To summarise evidence from randomised trials on the effects of treatment regimens on death and relapse.
SEARCH STRATEGY
Cochrane Controlled Trials Register, MEDLINE, EMBASE, BIOSIS from 1966 to September 2000 using MeSH terms "pseudomallei", "melioidosis" together with the terms "randomized-controlled-trial", "random allocation"; reference lists in articles on melioidosis; contact with trialists.
SELECTION CRITERIA
Randomised and quasi-randomised trials assessing treatments in patients with melioidosis.
DATA COLLECTION AND ANALYSIS
Eligibility and trial quality was assessed by two reviewers independently.
MAIN RESULTS
For intravenous therapy in the acute phase, we identified five trials with a total of 519 patients. Chloramphenicol, doxycycline, and co-trimoxazole (trimethoprim-sulphamethoxazole) combination regimens were associated with a mortality of 50% or more (two studies). Patients randomised to regimens that included ceftazidime were more likely to survive (relative risk [RR] 0.46, 95% confidence interval [CI] 0.30 to 0.71). When ceftazidime-containing regimens were compared with beta lactam or alternative beta lactamase inhibitor regimens such as co-amoxiclav (amoxycillin-clavulanic acid) and cefoperazone-sulbactam, mortality rates were similar (RR 1.10, 95% CI 0.83 to 1.46), as was the case in one trial of imipenem. For oral therapy in the maintenance phase, we found two trials of 188 participants. Results showed that treatment with the conventional regimen (chloramphenicol, doxycycline, and trimethoprim-sulphamethoxazole) resulted in fewer fatalities in patients compared to a regimen of amoxycillin-clavulanic acid and doxycycline alone.
REVIEWER'S CONCLUSIONS
Regimens for the acute phase of illness should contain ceftazidime or imipenem. It is not yet clear if combinations of treatments in the early phase reduce relapse. For oral therapy after the acute phase of treatment, trials suggest that conventional four drug regimens can be used for treatment.
Topics: Administration, Oral; Anti-Bacterial Agents; Drug Therapy, Combination; Humans; Injections, Intravenous; Melioidosis; Randomized Controlled Trials as Topic
PubMed: 11405983
DOI: 10.1002/14651858.CD001263 -
BMJ Case Reports Jul 2019We reported a case of a young female patient presented with sepsis and diagnosed with melioidosis and systemic lupus erythematosus (SLE) within the same admission. She...
We reported a case of a young female patient presented with sepsis and diagnosed with melioidosis and systemic lupus erythematosus (SLE) within the same admission. She presented with 1-week history of productive cough, progressive dyspnoea together with prolonged fever, arthralgia, rashes and oral ulcers. She had septicemic shock, respiratory failure requiring intubation and ventilation in intensive care unit and subsequently developed acute renal failure requiring haemodialysis. Antibiotics and immunosuppressive treatment including low-dose intravenous cyclophosphamide were commenced. She had a remarkable recovery and was discharged after 6 weeks. There was no evidence of active SLE or relapse of melioidosis during clinic follow-ups.
Topics: Adult; Anti-Bacterial Agents; Cyclophosphamide; Diagnosis, Differential; Female; Humans; Immunosuppressive Agents; Lupus Erythematosus, Systemic; Melioidosis; Renal Dialysis; Renal Insufficiency; Sepsis
PubMed: 31266760
DOI: 10.1136/bcr-2019-229974 -
Microbes and Infection Nov 2016Research released in 2016 shows that the global burden of Burkholderia pseudomallei infection is probably much higher than previously suspected. Better testing and...
Research released in 2016 shows that the global burden of Burkholderia pseudomallei infection is probably much higher than previously suspected. Better testing and reporting are needed if we are to detect outbreaks and diminish deadly delays in treatment. Worldwide, researchers need support for vaccine development, particularly for public health vaccines to protect people and animals in endemic areas. Because melioidosis can infect so many species, collaboration and communication between human and veterinary medicine experts will be key to tracking, treating and preventing B. pseudomallei infections.
Topics: Animals; Bacterial Vaccines; Burkholderia pseudomallei; Cost of Illness; Drug Discovery; Global Health; Humans; Intersectoral Collaboration; Melioidosis
PubMed: 27436814
DOI: 10.1016/j.micinf.2016.07.001