1
|
Smith S, Buikstra E, Rubenach S, Preston-Thomas A, Hanson J. Limited Awareness of Melioidosis in High-risk Populations Despite an Increasing Incidence of the Disease in Far North Queensland, Australia. Am J Trop Med Hyg 2022; 107:1278-1280. [PMID: 35895342 PMCID: PMC9768265 DOI: 10.4269/ajtmh.22-0160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 05/17/2022] [Indexed: 12/30/2022] Open
Abstract
The incidence of melioidosis, an opportunistic infection caused by Burkholderia pseudomallei, has recently doubled in Far North Queensland (FNQ), Australia. This contrasts with the local burden of dengue, which is nearing elimination, and the stable incidence of leptospirosis. This questionnaire-based study assessed the awareness of melioidosis among people in FNQ with risk factors for the disease, using awareness of leptospirosis and dengue as comparators. There were 427 respondents; 361 (85%) reported one or more risk factors for melioidosis. Only 69 of 361 (19%) had heard of melioidosis compared with 301 of 361 (83%) who had heard of dengue (P < 0.001) and 137 of 361 (38%) who had heard of leptospirosis (P < 0.001). In FNQ, Australia, there is an increasing local incidence of melioidosis, but there is limited awareness of the disease among high-risk individuals. Greater community awareness of melioidosis is necessary to implement strategies to prevent disease and expedite the presentation of patients with this life-threatening infection.
Collapse
Affiliation(s)
- Simon Smith
- Department of Medicine, Cairns Hospital, Cairns, Queensland, Australia
| | | | - Sally Rubenach
- Tropical Public Health Services, Cairns, Queensland, Australia
| | | | - Josh Hanson
- Department of Medicine, Cairns Hospital, Cairns, Queensland, Australia
- The Kirby Institute, New South Wales, Australia
| |
Collapse
|
2
|
Efficacy of Co-Trimoxazole against Experimental Melioidosis Acquired by Different Routes of Infection. Antimicrob Agents Chemother 2022; 66:e0070822. [PMID: 36226972 DOI: 10.1128/aac.00708-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Burkholderia pseudomallei is the causative agent of melioidosis and presents with diverse clinical manifestations. Naturally occurring infection occurs following contamination of cuts or skin abrasions, or ingestion of contaminated water, and occasionally through inhalational of infected soil or water particles. The influence of the route of disease acquisition on the efficacy of medical countermeasures has not been explored in humans or in appropriate animal models. The efficacy of co-trimoxazole against melioidosis acquired by different routes of exposure was assessed in postexposure prophylaxis (PEP) and treatment studies in marmoset models of melioidosis. Following challenge with B. pseudomallei by the inhalational, subcutaneous, or ingestion routes of administration, animals were given co-trimoxazole at 12 hourly intervals for 14 days, starting either 6 h postchallenge or at the onset of fever. Animals were then observed for 28 days. All animals that received antibiotic 6 h postchallenge survived the duration of dosing. All animals that received antibiotics at the onset of fever completed the treatment, but 10%, 57%, and 60% of those with ingestion, subcutaneous, and inhalation challenge relapsed, respectively. Bacteriological and histological differences were observed between placebo-control animals and those that relapsed. Immunological profiles indicate difference between animals given placebo and those that relapsed or survived the duration of the study. A broad T-cell activation was observed in animals that survived. Overall, these data suggest the efficacy of co-trimoxazole, as measured in the incidence of relapse, differs depending on the disease-acquisition route. Therefore, there are implications in treating this disease in regions of endemicity.
Collapse
|
3
|
Savelkoel J, Dance DAB, Currie BJ, Limmathurotsakul D, Wiersinga WJ. A call to action: time to recognise melioidosis as a neglected tropical disease. THE LANCET INFECTIOUS DISEASES 2022; 22:e176-e182. [DOI: 10.1016/s1473-3099(21)00394-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 05/07/2021] [Accepted: 06/28/2021] [Indexed: 10/19/2022]
|
4
|
Chieng R. Melioidosis. WIKIJOURNAL OF MEDICINE 2022. [DOI: 10.15347/wjm/2022.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
5
|
Fairhead LJ, Smith S, Sim BZ, Stewart AGA, Stewart JD, Binotto E, Law M, Hanson J. The seasonality of infections in tropical Far North Queensland, Australia: A 21-year retrospective evaluation of the seasonal patterns of six endemic pathogens. PLOS GLOBAL PUBLIC HEALTH 2022; 2:e0000506. [PMID: 36962353 PMCID: PMC10021965 DOI: 10.1371/journal.pgph.0000506] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 04/27/2022] [Indexed: 01/17/2023]
Abstract
An understanding of the seasonality of infections informs public health strategies and assists clinicians in their management of patients with undifferentiated illness. The seasonality of infections is driven by a variety of environmental and human factors; however, the role of individual climatic factors has garnered much attention. This study utilises Poisson regression models to assess the seasonality of six important infections in tropical Australia and their association with climatic factors and severe weather events over a 21-year period. Melioidosis and leptospirosis showed marked wet season predominance, while more cases of rickettsial disease and cryptococcosis were seen in cooler, drier months. Staphylococcus aureus infections were not seasonal, while influenza demonstrated inter-seasonality. The climate did not significantly change during the 21 years of the study period, but the incidence of melioidosis and rickettsial disease increased considerably, highlighting the primacy of other factors-including societal inequality, and the impact of urban expansion-in the incidence of these infections. While anthropogenic climate change poses a threat to the region-and may influence the burden of these infections in the future-this study highlights the fact that, even for seasonal diseases, other factors presently have a greater effect on disease incidence. Public health strategies must also target these broader drivers of infection if they are to be effective.
Collapse
Affiliation(s)
- Lee J Fairhead
- Department of Medicine, Cairns Hospital, Cairns, Queensland, Australia
| | - Simon Smith
- Department of Medicine, Cairns Hospital, Cairns, Queensland, Australia
| | - Beatrice Z Sim
- Infectious Diseases Service, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | | | - James D Stewart
- Department of Medicine, Cairns Hospital, Cairns, Queensland, Australia
| | - Enzo Binotto
- Department of Medicine, Cairns Hospital, Cairns, Queensland, Australia
| | - Matthew Law
- The Kirby Institute, University of New South Wales, Sydney, New South Wales, Australia
| | - Josh Hanson
- Department of Medicine, Cairns Hospital, Cairns, Queensland, Australia
- The Kirby Institute, University of New South Wales, Sydney, New South Wales, Australia
| |
Collapse
|
6
|
Hanson J, Smith S, Stewart J, Horne P, Ramsamy N. Melioidosis-a disease of socioeconomic disadvantage. PLoS Negl Trop Dis 2021; 15:e0009544. [PMID: 34153059 PMCID: PMC8248627 DOI: 10.1371/journal.pntd.0009544] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 07/01/2021] [Accepted: 06/07/2021] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND There is growing recognition of the contribution of the social determinants of health to the burden of many infectious diseases. However, the relationship between socioeconomic status and the incidence and outcome of melioidosis is incompletely defined. METHODS All residents of Far North Queensland, tropical Australia with culture-proven melioidosis between January 1998 and December 2020 were eligible for the study. Their demographics, comorbidities and socioeconomic status were correlated with their clinical course. Socioeconomic status was determined using the Socio-Economic Indexes for Areas (SEIFA) Index of Relative Socio-economic Disadvantage score, a measure of socioeconomic disadvantage developed by the Australian Bureau of Statistics. Socioeconomic disadvantage was defined as residence in a region with a SEIFA score in the lowest decile in Australia. RESULTS 321 eligible individuals were diagnosed with melioidosis during the study period, 174 (54.2%) identified as Indigenous Australians; 223/321 (69.5%) were bacteraemic, 85/321 (26.5%) required Intensive Care Unit (ICU) admission and 37/321 (11.5%) died. 156/321 (48.6%) were socioeconomically disadvantaged, compared with 56603/269002 (21.0%) of the local general population (p<0.001). Socioeconomically disadvantaged patients were younger, more likely to be female, Indigenous, diabetic or have renal disease. They were also more likely to die prior to hospital discharge (26/156 (16.7%) versus 11/165 (6.7%), p = 0.002) and to die at a younger age (median (IQR) age: 50 (38-68) versus 65 (59-81) years, p = 0.02). In multivariate analysis that included age, Indigenous status, the presence of bacteraemia, ICU admission and the year of hospitalisation, only socioeconomic disadvantage (odds ratio (OR) (95% confidence interval (CI)): 2.49 (1.16-5.35), p = 0.02) and ICU admission (OR (95% CI): 4.79 (2.33-9.86), p<0.001) were independently associated with death. CONCLUSION Melioidosis is disease of socioeconomic disadvantage. A more holistic approach to the delivery of healthcare which addresses the social determinants of health is necessary to reduce the burden of this life-threatening disease.
Collapse
Affiliation(s)
- Josh Hanson
- Kirby Institute, University of New South Wales, Sydney, Australia
- Department of Medicine, Cairns Hospital, Cairns, Queensland, Australia
- * E-mail:
| | - Simon Smith
- Department of Medicine, Cairns Hospital, Cairns, Queensland, Australia
| | - James Stewart
- Department of Medicine, Cairns Hospital, Cairns, Queensland, Australia
| | - Peter Horne
- Tropical Public Health Service, Cairns, Queensland, Australia
| | - Nicole Ramsamy
- Torres and Cape Hospital and Health Service, Cairns, Queensland, Australia
| |
Collapse
|
7
|
Abstract
The causative agent of melioidosis, Burkholderia pseudomallei, a tier 1 select agent, is endemic in Southeast Asia and northern Australia, with increased incidence associated with high levels of rainfall. Increasing reports of this condition have occurred worldwide, with estimates of up to 165,000 cases and 89,000 deaths per year. The ecological niche of the organism has yet to be clearly defined, although the organism is associated with soil and water. The culture of appropriate clinical material remains the mainstay of laboratory diagnosis. Identification is best done by phenotypic methods, although mass spectrometric methods have been described. Serology has a limited diagnostic role. Direct molecular and antigen detection methods have limited availability and sensitivity. Clinical presentations of melioidosis range from acute bacteremic pneumonia to disseminated visceral abscesses and localized infections. Transmission is by direct inoculation, inhalation, or ingestion. Risk factors for melioidosis include male sex, diabetes mellitus, alcohol abuse, and immunosuppression. The organism is well adapted to intracellular survival, with numerous virulence mechanisms. Immunity likely requires innate and adaptive responses. The principles of management of this condition are drainage and debridement of infected material and appropriate antimicrobial therapy. Global mortality rates vary between 9% and 70%. Research into vaccine development is ongoing.
Collapse
Affiliation(s)
- I Gassiep
- Pathology Queensland, Townsville Hospital, Townsville, Queensland, Australia
- Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia
| | - M Armstrong
- Pathology Queensland, Townsville Hospital, Townsville, Queensland, Australia
| | - R Norton
- Pathology Queensland, Townsville Hospital, Townsville, Queensland, Australia
- Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia
| |
Collapse
|