RESUMEN
Melioidosis, caused by the bacterium Burkholderia pseudomallei, is an uncommon infection that is typically associated with exposure to soil and water in tropical and subtropical environments. It is rarely diagnosed in the continental United States. Patients with melioidosis in the United States commonly report travel to regions where melioidosis is endemic. We report a cluster of four non-travel-associated cases of melioidosis in Georgia, Kansas, Minnesota, and Texas. These cases were caused by the same strain of B. pseudomallei that was linked to an aromatherapy spray product imported from a melioidosis-endemic area.
Asunto(s)
Aromaterapia/efectos adversos , Burkholderia pseudomallei/aislamiento & purificación , Brotes de Enfermedades , Melioidosis/epidemiología , Aerosoles , Encéfalo/microbiología , Encéfalo/patología , Burkholderia pseudomallei/genética , COVID-19/complicaciones , Preescolar , Resultado Fatal , Femenino , Genoma Bacteriano , Humanos , Pulmón/microbiología , Pulmón/patología , Masculino , Melioidosis/complicaciones , Persona de Mediana Edad , Filogenia , Choque Séptico/microbiología , Estados Unidos/epidemiologíaRESUMEN
Burkholderia pseudomallei is the environmental bacillus that causes melioidosis; a disease clinically significant in Australia and Southeast Asia but emerging in tropical and sub-tropical regions around the globe. Previous studies have placed the ancestral population of the organism in Australia with a single lineage disseminated to Southeast Asia. We have previously characterized B. pseudomallei isolates from New Guinea and the Torres Strait archipelago; remote regions that share paleogeographic ties with Australia. These studies identified regional biogeographical boundaries. In this study, we utilize whole-genome sequencing to reconstruct ancient evolutionary relationships and ascertain correlations between paleogeography and present-day distribution of this bacterium in Australasia. Our results indicate that B. pseudomallei from New Guinea fall into a single clade within the Australian population. Furthermore, clades from New Guinea are region-specific; an observation possibly linked to limited recent anthropogenic influence in comparison to mainland Australia and Southeast Asia. Isolates from the Torres Strait archipelago were distinct yet scattered among those from mainland Australia. These results provide evidence that the New Guinean and Torres Strait lineages may be remnants of an ancient portion of the Australian population. Rising sea levels isolated New Guinea and the Torres Strait Islands from each other and the Australian mainland, and may have allowed long-term isolated evolution of these lineages, providing support for a theory of microbial biogeography congruent with that of macro flora and fauna. Moreover, these findings indicate that contemporary microbial biogeography theories should consider recent and ongoing impacts of globalisation and human activity.
Asunto(s)
Burkholderia pseudomallei/genética , ADN Bacteriano/genética , Melioidosis/genética , Filogenia , Antropología Médica/historia , Australasia , Australia , Burkholderia pseudomallei/patogenicidad , Variación Genética , Historia Antigua , Humanos , Melioidosis/microbiología , Nueva Guinea , Secuenciación Completa del GenomaRESUMEN
Melioidosis is a tropical disease caused by the bacterium Burkholderia pseudomallei. Outbreaks are uncommon and can generally be attributed to a single point source and strain. We used whole-genome sequencing to analyse B. pseudomallei isolates collected from an historical 2-year long case cluster that occurred in a remote northern Australian indigenous island community, where infections were previously linked to a contaminated communal water supply. We analysed the genome-wide relatedness of the two most common multilocus sequence types (STs) involved in the outbreak, STs 125 and 126. This analysis showed that although these STs were closely related on a whole-genome level, they demonstrated evidence of multiple recombination events that were unlikely to have occurred over the timeframe of the outbreak. Based on epidemiological and genetic data, we also identified two additional patients not previously associated with this outbreak. Our results confirm the previous hypothesis that a single unchlorinated water source harbouring multiple B. pseudomallei strains was linked to the outbreak, and that increased melioidosis risk in this community was associated with Piper methysticum root (kava) consumption.
Asunto(s)
Burkholderia pseudomallei/genética , Genoma Bacteriano , Melioidosis/microbiología , Australia/epidemiología , Brotes de Enfermedades , Humanos , Kava/microbiología , Melioidosis/epidemiología , Tipificación de Secuencias MultilocusRESUMEN
OBJECTIVE: To investigate the effectiveness of hot water immersion for relieving the pain of major box jellyfish (Chironex fleckeri) stings.Design, interventions: Open label, randomised controlled trial comparing the effects of hot water immersion (45°C) and icepacks.Setting, participants: 42 patients with suspected C. fleckeri stings treated in the emergency department of the Royal Darwin Hospital during September 2005 - October 2008. MAIN OUTCOME MEASURES: The primary outcome was pain severity, assessed with a visual analogue scale (VAS). Secondary outcomes included crossover to the alternative treatment, use of opioid analgesia, emergency department length of stay (LOS), and delayed urticaria. RESULTS: Of 42 patients (26 males; median age, 19 years; IQR, 13-27 years), 25 were allocated to icepack treatment and 17 to hot water immersion. The demographic and baseline VAS data for the two groups were similar. After 30 minutes of treatment, 11 patients (65%) treated with hot water and 14 (56%) treated with icepacks had clinically improved pain scores (absolute difference, 9%; 95% CI, -22% to 39%; P = 0.75). One patient treated with icepacks crossed over to heat immersion. Two patients in each arm received intravenous opioid analgesia. Median emergency department LOS was 1.6 h (IQR, 1.0-1.8 h) for icepack patients and 2.1 h (IQR, 1.6-2.8 h) for heat immersion patients (P = 0.07). Five of seven patients who were followed up developed delayed urticaria. CONCLUSION: Hot water immersion was no more effective than icepacks for reducing the acute pain of box jellyfish stings, but increased emergency department LOS by about 30 minutes. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry, ACTRN12605000007639.
Asunto(s)
Mordeduras y Picaduras/terapia , Cubomedusas , Calor/uso terapéutico , Hielo , Inmersión , Adolescente , Adulto , Analgésicos Opioides/uso terapéutico , Animales , Mordeduras y Picaduras/complicaciones , Femenino , Humanos , Masculino , Dolor/etiología , Manejo del Dolor/métodos , Dimensión del Dolor , Resultado del Tratamiento , Urticaria/etiología , Adulto JovenRESUMEN
STUDY OBJECTIVE: We describe Irukandji syndrome (a painful hypercatecholaminergic condition caused by jellyfish envenoming) in Australia's Northern Territory. METHODS: We collected prospectively a standardized data set on patients presenting to health facilities in the Northern Territory. Additional cases were identified retrospectively. Data collected included demographic, geographic, seasonal, and environmental features, as well as sting details, clinical manifestations, investigations, management, and outcomes. RESULTS: From 1990 to 2007, Irukandji syndrome affected 87 people. Age ranged from 1 to 51 years (64% male victims; 41% children [63% indigenous]). Activities associated with stings included snorkeling or scuba diving (35%) and swimming (29%). Stings commonly occurred in water greater than 2 m deep (63%), with fine weather (73%) and still or light breeze (70%). Seasonal variation was bimodal; peaks in May and October corresponded to prevailing offshore winds in the Darwin and Gove areas, respectively. Pain was severe (65%), with rapid onset (<30 minutes in 79%). Sting lesions (visible in 63%) were mild, and nematocysts (detected in 7 cases) had variable morphology. Systemic features were common, including hypertension and ECG abnormalities. Severe complications included troponin-level increases (2 cases) and cardiomyopathy with ventricular tachycardia (1 case), but no fatalities. Management included vinegar as first aid (66%), parenteral opioids (70%) (range 2 to 82.5 mg morphine equivalents in adults), and magnesium sulfate (3 cases). Hospital admission (49%) and aeromedical retrieval (16%) were commonplace. CONCLUSION: Irukandji syndrome in the Northern Territory was clinically consistent with previous studies but had distinct seasonal, geographic, and environmental features. Indigenous children in remote coastal communities are at risk, and there is room for improvement in prevention and management.
Asunto(s)
Mordeduras y Picaduras/complicaciones , Cardiomiopatías/etiología , Hipertensión/etiología , Dolor/etiología , Escifozoos , Natación/lesiones , Ácido Acético/uso terapéutico , Adolescente , Adulto , Analgésicos Opioides/uso terapéutico , Anestésicos/uso terapéutico , Animales , Antivenenos/uso terapéutico , Mordeduras y Picaduras/epidemiología , Mordeduras y Picaduras/terapia , Niño , Preescolar , Venenos de Cnidarios/antagonistas & inhibidores , Femenino , Primeros Auxilios , Hospitalización , Humanos , Hipertensión/terapia , Indicadores y Reactivos/uso terapéutico , Lactante , Sulfato de Magnesio/uso terapéutico , Masculino , Persona de Mediana Edad , Northern Territory/epidemiología , Dolor/diagnóstico , Manejo del Dolor , Dimensión del Dolor , Venenos/uso terapéutico , Estudios Prospectivos , Estudios Retrospectivos , Estaciones del Año , Síndrome , Resultado del Tratamiento , Adulto JovenRESUMEN
Limited effective treatments, coupled with recent observations of emerging drug resistance to oral ivermectin and 5% permethrin, raise concerns regarding the future control of scabies, especially in severe cases and in endemic areas where repeated community treatment programs are in place. There is consequently an urgent need to define molecular mechanisms of drug resistance in scabies mites and to develop and assess alternative therapeutic options, such as tea tree oil, in the event of increasing treatment failure. Molecular studies on scabies mites have, until recently, been restricted; however, recent advances are providing new insights into scabies mite biology and genetic mechanisms underlying drug resistance. These may assist in overcoming many of the current difficulties in monitoring treatment efficacy and allow the development of more sensitive tools for monitoring emerging resistance.
Asunto(s)
Ivermectina/uso terapéutico , Permetrina/uso terapéutico , Escabiosis/tratamiento farmacológico , Animales , Resistencia a Medicamentos , Humanos , Insecticidas/uso terapéutico , Sarcoptes scabiei/efectos de los fármacos , Escabiosis/diagnóstico , Aceite de Árbol de Té/uso terapéuticoRESUMEN
AIM: To identify factors that affect rheumatic fever prophylaxis for remote-living Aboriginal patients, and to determine the proportion who received adequate prophylaxis. DESIGN AND SETTING: Interview (with analysis based on principles of grounded theory) of patients with a history of rheumatic fever or rheumatic heart disease and their relatives, and health service providers in a remote Aboriginal community; audit of benzathine penicillin coverage of patients with rheumatic heart disease. PARTICIPANTS: 15 patients with rheumatic heart disease or a history of rheumatic fever, 18 relatives and 18 health care workers. RESULTS: Patients felt that the role of the clinic was not only to care for them physically, but that staff should also show nurturing holistic care to generate trust and treatment compliance. Differing expectations between patients and health care providers relating to the responsibility for care of patients absent from the community was a significant factor in patients missing injections. Neither a biomedical understanding of the disease nor a sense of taking responsibility for one's own health were clearly related to treatment uptake. Patients did not generally refuse injections, and 59% received adequate prophylaxis (> 75% of prescribed injections). CONCLUSION: In this Aboriginal community, concepts of being cared for and nurtured, and belonging to a health service were important determinants of compliance.
Asunto(s)
Antibacterianos/uso terapéutico , Conocimientos, Actitudes y Práctica en Salud , Accesibilidad a los Servicios de Salud , Servicios de Salud del Indígena , Nativos de Hawái y Otras Islas del Pacífico/psicología , Penicilina G Benzatina/uso terapéutico , Fiebre Reumática/etnología , Fiebre Reumática/prevención & control , Negativa del Paciente al Tratamiento/etnología , Femenino , Humanos , Masculino , Área sin Atención Médica , Persona de Mediana Edad , Northern Territory , Satisfacción del Paciente/etnologíaRESUMEN
OBJECTIVE: To compare the acaricidal activity of Melaleuca alternifolia (tea tree) oil (TTO) and some of its individual active components on the itch mite Sarcoptes scabiei var hominis. DESIGN: In vitro acaricide sensitivity assessment. SETTING: The Menzies School of Health Research laboratory, located near the Infectious Diseases Ward of the Royal Darwin Hospital, Australia, where patients are admitted and treated for crusted scabies. PARTICIPANTS: Scabies mites (S scabiei var hominis) were collected from a 20-year-old Aboriginal woman admitted to the Royal Darwin Hospital with crusted scabies. Interventions Within 3 hours of collection, scabies mites were placed in continuous direct contact with the TTO products and control acaricides and were observed at regular intervals. MAIN OUTCOME MEASURES: Percentage of mites dead at regular observation intervals between 5 minutes and 24 hours during continuous exposure to the TTO products and acaricides. RESULTS: The 5% TTO and active component terpinen-4-ol were highly effective in reducing mite survival times. Statistically significant differences in mite survival curves were observed for 5% TTO, 2.1% terpinen-4-ol, 5% permethrin, and ivermectin (100 microg/g of Emulsifying Ointment British Pharmacopoeia 88). In vivo effectiveness was also observed. CONCLUSIONS: Documentation of resistance against antiectoparasitic compounds is increasing. Reported S scabiei treatment failures with lindane, crotamiton, and benzyl benzoate, as well as likely emerging resistance to 5% permethrin and oral ivermectin, are of concern and advocate for the identification and development of novel acaricidal drugs. Tea tree oil is a membrane-active biocide extracted from the tree M alternifolia. It is a principal antimicrobial in a wide range of pharmaceuticals sold in Australia, with the main active component being oxygenated terpenoids. The results suggest that TTO has a potential role as a new topical acaricide and confirm terpinen-4-ol as the primary active component.
Asunto(s)
Insecticidas/farmacología , Melaleuca , Fitoterapia , Sarcoptes scabiei/efectos de los fármacos , Escabiosis/tratamiento farmacológico , Aceite de Árbol de Té/farmacología , Adulto , Animales , Femenino , Humanos , Concentración 50 Inhibidora , Insecticidas/administración & dosificación , Insecticidas/uso terapéutico , Aceite de Árbol de Té/administración & dosificación , Aceite de Árbol de Té/uso terapéuticoRESUMEN
Kava is an extract from the Piper methysticum Forst. f. plant that has social and spiritual importance in Pacific islands societies. Herbal remedies that contain kava are used for the psychiatric treatment of anxiety and insomnia. Laboratory studies have found only subtle, if any, changes on cognitive or motor functions from the acute effects of consuming small clinical doses of kava products. Intoxication from recreational doses of kava has not been studied. The performance of individuals intoxicated from drinking kava (n=11) was compared with a control group (n=17) using saccade and cognitive tests. On average, intoxicated individuals had consumed 205 g of kava powder each (approximately 150 times clinical doses) in a group session that went for 14.4 h and ended 8 h prior to testing. Intoxicated kava drinkers showed ataxia, tremors, sedation, blepharospasm and elevated liver enzymes (GGT and ALP), together with saccadic dysmetria, saccadic slowing and reduced accuracy performing a visual search task that only became evident as the task complexity increased. Kava intoxication is characterized by specific abnormalities of movement coordination and visual attention but normal performance of complex cognitive functions. Saccade abnormalities suggest disruption of cerebellar and GABAergic functions.
Asunto(s)
Cognición/efectos de los fármacos , Kava/química , Movimientos Sacádicos/efectos de los fármacos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Extractos Vegetales/efectos adversos , Trastornos Relacionados con Sustancias/psicologíaRESUMEN
Clinical toxinology encompasses a broad range of medical conditions resulting from envenomation by venomous terrestrial and marine organisms, and also poisoning from ingestion of animal and plant toxins. Toxin-related disease is an important cause of morbidity and mortality worldwide, particularly in the tropical and subtropical continents. Snake bite is the single most important toxin-related disease, causing substantial mortality in many parts of Africa, Asia, and the Americas. The most important snake families are Viperidae and Elapidae, causing a range of clinical effects including local necrosis, neurotoxicity, coagulopathy and hemorrhage, myotoxicity and renal toxicity. These effects vary according to geography and group of snake. Arachnid envenomation results mainly in morbidity, particularly scorpion stings which can cause severe systemic envenomation. Spider bite is far less of a problem, and the majority of medically important cases can be attributed to widow spiders (Latrodectus spp.) and recluse spiders (Loxosceles spp.). Marine-related envenomations are common, but severe effects are less so. Plant and mushroom poisoning occur in most parts of the world, but the types and methods of poisoning vary considerably between continents. Management of toxin-related disease is often difficult, and in many cases meticulous supportive care is all that is available. The mainstay of treatment is the use of antivenoms for many envenomations and poisoning, although these do not exist for all dangerous organisms. Unfortunately antivenoms are not an economically viable product, so development and manufacture of these agents have been limited. This is now further worsened by a current shortage of antivenom. There is a need for improvement in the preventionand management of toxin-related disease. This will require well-designed studies to define the extent of the problem, initiatives to improve the prevention and management of these conditions, and development of new, and continuation of current, antivenom supplies.
Asunto(s)
Antídotos/uso terapéutico , Antivenenos/uso terapéutico , Mordeduras y Picaduras/terapia , Intoxicación por Plantas/terapia , Animales , Mordeduras y Picaduras/epidemiología , Humanos , Intoxicación por Plantas/epidemiologíaRESUMEN
Kava is an extract from the Piper methysticum Forst. f. plant that has been consumed in the Pacific islands for millennia and more recently, among indigenous populations, in northern Australia and throughout the Western world as an herbal medicine. Through alterations on neuronal excitation, kava induces muscle relaxation, anasthesia, and has anxiolytic properties. There have been several isolated reports of psychotic syndromes, severe choreoathetosis and possible seizures following kava use. However, there is no conclusive evidence that kava interferes with normal cognitive processes. We tested a group of current, ex, and nonkava users among an indigenous population in northern Australia, using saccade and cognitive tests that have proven cross-cultural validity and are sensitive to subtle disruptions of the brain arising from substance abuse or neuropsychiatric illness. Despite collecting data from among the heaviest reported kava drinkers in the world, we found no impairment in cognitive or saccade function in individuals who were currently heavy kava users (and had been for up to 18 years), nor was there any impairment in individuals who had been heavy kava users in the past but had abstained for longer than 6 months. Current and ex-kava users showed a higher rate of kava dermopathy, lower body mass index, lowered blood lymphocytes and, in addition, current kava users showed elevated liver enzymes. While there has recently been increasing concern about potentially fatal liver damage attributed to kava use, we have found no evidence of brain dysfunction in heavy and long-term kava users.