RESUMEN
The decline of the iconic monarch butterfly (Danaus plexippus) in North America has motivated research on the impacts of land use and land cover (LULC) change and climate variability on monarch habitat and population dynamics. We investigated spring and fall trends in LULC, milkweed and nectar resources over a 20-year period, and ~ 30 years of climate variables in Mexico and Texas, U.S. This region supports spring breeding, and spring and fall migration during the annual life cycle of the monarch. We estimated a - 2.9% decline in milkweed in Texas, but little to no change in Mexico. Fall and spring nectar resources declined < 1% in both study extents. Vegetation greenness increased in the fall and spring in Mexico while the other climate variables did not change in both Mexico and Texas. Monarch habitat in Mexico and Texas appears relatively more intact than in the midwestern, agricultural landscapes of the U.S. Given the relatively modest observed changes in nectar and milkweed, the relatively stable climate conditions, and increased vegetation greenness in Mexico, it seems unlikely that habitat loss (quantity or quality) in Mexico and Texas has caused large declines in population size or survival during migration.
Asunto(s)
Asclepias , Mariposas Diurnas , Animales , México , Texas , Néctar de las Plantas , Migración Animal , Fitomejoramiento , EcosistemaRESUMEN
Phylogenetic analysis of a clinical isolate associated with subclinical Burkholderia pseudomallei infection revealed probable exposure in the British Virgin Islands, where reported infections are limited. Clinicians should consider this geographic distribution when evaluating possible infection among persons with compatible travel history.
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Burkholderia pseudomallei , Melioidosis , Islas Vírgenes Británicas , Burkholderia pseudomallei/genética , Humanos , Melioidosis/diagnóstico , Melioidosis/epidemiología , Filogenia , ViajeRESUMEN
Burkholderia pseudomallei is a Gram-negative bacterium that causes the sapronotic disease melioidosis. An outbreak in 2003 in the state of Ceara, Brazil, resulted in subsequent surveillance and environmental sampling which led to the recognition of B. pseudomallei as an endemic pathogen in that area. From 2003 to 2015, 24 clinical and 12 environmental isolates were collected across Ceara along with one from the state of Alagoas. Using next-generation sequencing, multilocus sequence typing, and single nucleotide polymorphism analysis, we characterized the genomic diversity of this collection to better understand the population structure of B. pseudomallei associated with Ceara. We found that the isolates in this collection form a distinct subclade compared to other examples from the Western Hemisphere. Substantial genetic diversity among the clinical and environmental isolates was observed, with 14 sequence types (STs) identified among the 37 isolates. Of the 31,594 core single-nucleotide polymorphisms (SNPs) identified, a high proportion (59%) were due to recombination. Because recombination events do not follow a molecular clock, the observation of high occurrence underscores the importance of identifying and removing recombination SNPs prior to evolutionary reconstructions and inferences in public health responses to B. pseudomallei outbreaks. Our results suggest long-term B. pseudomallei prevalence in this recently recognized region of melioidosis endemicity.IMPORTANCEB. pseudomallei causes significant morbidity and mortality, but its geographic prevalence and genetic diversity are not well characterized, especially in the Western Hemisphere. A better understanding of the genetic relationships among clinical and environmental isolates will improve knowledge of the population structure of this bacterium as well as the ability to conduct epidemiological investigations of cases of melioidosis.
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Burkholderia pseudomallei/clasificación , Burkholderia pseudomallei/genética , Variación Genética , Genoma Bacteriano , Técnicas de Tipificación Bacteriana , Brasil/epidemiología , ADN Bacteriano/genética , Brotes de Enfermedades/estadística & datos numéricos , Genómica/métodos , Genotipo , Humanos , Masculino , Melioidosis/epidemiología , Melioidosis/microbiología , Filogenia , Análisis de Secuencia de ADNRESUMEN
We report an analysis of the genomic diversity of isolates of Burkholderia pseudomallei, the cause of melioidosis, recovered in Colombia from routine surveillance during 2016-2017. B. pseudomallei appears genetically diverse, suggesting it is well established and has spread across the region.
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Burkholderia pseudomallei , Melioidosis , Burkholderia pseudomallei/genética , Colombia/epidemiología , Genómica , Humanos , Melioidosis/epidemiología , Tipificación de Secuencias MultilocusRESUMEN
The distribution of Burkholderia pseudomallei in the Caribbean is poorly understood. We isolated B. pseudomallei from US Virgin Islands soil. The soil isolate was genetically similar to other isolates from the Caribbean, suggesting that B. pseudomallei might have been introduced to the islands multiple times through severe weather events.
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Burkholderia pseudomallei , Melioidosis , Microbiología del Suelo , Burkholderia pseudomallei/genética , Humanos , Islas , Melioidosis/epidemiología , Filogenia , Islas Virgenes de los Estados UnidosRESUMEN
We report 2 cases of melioidosis in women with diabetes admitted to an emergency department in the US Virgin Islands during October 2017. These cases emerged after Hurricanes Irma and Maria and did not have a definitively identified source. Poor outcomes were observed when septicemia and pulmonary involvement were present.
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Tormentas Ciclónicas , Melioidosis/epidemiología , Desastres Naturales , Anciano de 80 o más Años , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Burkholderia pseudomallei/efectos de los fármacos , Femenino , Humanos , Melioidosis/diagnóstico , Melioidosis/tratamiento farmacológico , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico , Islas Virgenes de los Estados Unidos/epidemiologíaRESUMEN
BACKGROUND: Burkholderia pseudomallei is a soil-dwelling bacterium and the causative agent of melioidosis. The global burden and distribution of melioidosis is poorly understood, including in the Caribbean. B. pseudomallei was previously isolated from humans and soil in eastern Puerto Rico but the abundance and distribution of B. pseudomallei in Puerto Rico as a whole has not been thoroughly investigated. METHODOLOGY/PRINCIPAL FINDINGS: We collected 600 environmental samples (500 soil and 100 water) from 60 sites around Puerto Rico. We identified B. pseudomallei by isolating it via culturing and/or using PCR to detect its DNA within complex DNA extracts. Only three adjacent soil samples from one site were positive for B. pseudomallei with PCR; we obtained 55 isolates from two of these samples. The 55 B. pseudomallei isolates exhibited fine-scale variation in the core genome and contained four novel genomic islands. Phylogenetic analyses grouped Puerto Rico B. pseudomallei isolates into a monophyletic clade containing other Caribbean isolates, which was nested inside a larger clade containing all isolates from Central/South America. Other Burkholderia species were commonly observed in Puerto Rico; we cultured 129 isolates from multiple soil and water samples collected at numerous sites around Puerto Rico, including representatives of B. anthina, B. cenocepacia, B. cepacia, B. contaminans, B. glumae, B. seminalis, B. stagnalis, B. ubonensis, and several unidentified novel Burkholderia spp. CONCLUSIONS/SIGNIFICANCE: B. pseudomallei was only detected in three soil samples collected at one site in north central Puerto Rico with only two of those samples yielding isolates. All previous human and environmental B. pseudomallei isolates were obtained from eastern Puerto Rico. These findings suggest B. pseudomallei is ecologically established and widely dispersed in the environment in Puerto Rico but rare. Phylogeographic patterns suggest the source of B. pseudomallei populations in Puerto Rico and elsewhere in the Caribbean may have been Central or South America.
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Burkholderia pseudomallei/aislamiento & purificación , Burkholderia/clasificación , Burkholderia/aislamiento & purificación , Burkholderia pseudomallei/genética , Islas Genómicas , Melioidosis , Filogenia , Reacción en Cadena de la Polimerasa/métodos , Puerto Rico , Análisis de Secuencia de ADN , Microbiología del Suelo , Microbiología del AguaRESUMEN
Melioidosis is caused by the gram-negative bacillus Burkholderia pseudomallei, endemic to northern Australia and Southeast Asia. We present a patient who traveled to Mexico, returned to the United States, and developed progressive manifestations of melioidosis, culminating as central nervous system disease. Standard therapy was contraindicated, and a prolonged intensive phase was employed.
RESUMEN
Melioidosis, a disease caused by the pathogen Burkholderia pseudomallei, is a significant underreported endemic disease found in tropical countries worldwide. Recent studies have demonstrated that human melioidosis cases have been increasingly recognized in the Americas. Therefore, the first Scientific Reunion of Melioidosis in the Americas was organized in Colombia, with the participation of health authorities of 11 Latin American countries and the United States. This report summarizes the topics reviewed during the meeting, including how to identify human infections and properly diagnose them, with the goal of increasing recognition of the disease in the Americas.
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Antibacterianos/uso terapéutico , Burkholderia pseudomallei/efectos de los fármacos , Melioidosis/diagnóstico , Melioidosis/tratamiento farmacológico , Américas/epidemiología , Antibacterianos/administración & dosificación , Bacteriemia/diagnóstico , Bacteriemia/epidemiología , Colombia , Humanos , Melioidosis/epidemiología , Viaje , Estados Unidos/epidemiologíaRESUMEN
Given the rapid population decline and recent petition for listing of the monarch butterfly (Danaus plexippus L.) under the Endangered Species Act, an accurate estimate of the Eastern, migratory population size is needed. Because of difficulty in counting individual monarchs, the number of hectares occupied by monarchs in the overwintering area is commonly used as a proxy for population size, which is then multiplied by the density of individuals per hectare to estimate population size. There is, however, considerable variation in published estimates of overwintering density, ranging from 6.9-60.9 million ha-1. We develop a probability distribution for overwinter density of monarch butterflies from six published density estimates. The mean density among the mixture of the six published estimates was â¼27.9 million butterflies ha-1 (95% CI [2.4-80.7] million ha-1); the mixture distribution is approximately log-normal, and as such is better represented by the median (21.1 million butterflies ha-1). Based upon assumptions regarding the number of milkweed needed to support monarchs, the amount of milkweed (Asclepias spp.) lost (0.86 billion stems) in the northern US plus the amount of milkweed remaining (1.34 billion stems), we estimate >1.8 billion stems is needed to return monarchs to an average population size of 6 ha. Considerable uncertainty exists in this required amount of milkweed because of the considerable uncertainty occurring in overwinter density estimates. Nevertheless, the estimate is on the same order as other published estimates. The studies included in our synthesis differ substantially by year, location, method, and measures of precision. A better understanding of the factors influencing overwintering density across space and time would be valuable for increasing the precision of conservation recommendations.
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Melioidosis is a bacterial infection caused by Burkholderia pseudomallei, a gram-negative saprophytic bacillus. Cases occur sporadically in the Americas with an increasing number of cases observed among people with no travel history to endemic countries. To better understand the incidence of the disease in the Americas, we reviewed the literature, including unpublished cases reported to the Centers for Disease Control and Prevention. Of 120 identified human cases, occurring between 1947 and June 2015, 95 cases (79%) were likely acquired in the Americas; the mortality rate was 39%. Burkholderia pseudomallei appears to be widespread in South, Central, and North America.
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Melioidosis/epidemiología , Burkholderia pseudomallei , Región del Caribe/epidemiología , América Central/epidemiología , Humanos , Incidencia , América del Norte/epidemiología , América del Sur/epidemiologíaAsunto(s)
Antibacterianos/uso terapéutico , Burkholderia pseudomallei/patogenicidad , Melioidosis/tratamiento farmacológico , Viaje , Antibacterianos/administración & dosificación , Burkholderia pseudomallei/genética , Femenino , Humanos , Melioidosis/epidemiología , Melioidosis/patología , México/epidemiología , Persona de Mediana Edad , Filogenia , Estados Unidos/epidemiologíaRESUMEN
PROBLEM/CONDITION: Melioidosis is an infection caused by the Gram-negative bacillus Burkholderia pseudomallei, which is naturally found in water and soil in areas endemic for melioidosis. Infection can be severe and sometimes fatal. The federal select agent program designates B. pseudomallei as a Tier 1 overlap select agent, which can affect both humans and animals. Identification of B. pseudomallei and all occupational exposures must be reported to the Federal Select Agent Program immediately (i.e., within 24 hours), whereas states are not required to notify CDC's Bacterial Special Pathogens Branch (BSPB) of human infections. PERIOD COVERED: 2008-2013. DESCRIPTION OF SYSTEM: The passive surveillance system includes reports of suspected (human and animal) melioidosis cases and reports of incidents of possible occupational exposures. Reporting of suspected cases to BSPB is voluntary. BSPB receives reports of occupational exposure in the context of a request for technical consultation (so that the system does not include the full complement of the mandatory and confidential reporting to the Federal Select Agent Program). Reporting sources include state health departments, medical facilities, microbiologic laboratories, or research facilities. Melioidosis cases are classified using the standard case definition adopted by the Council of State and Territorial Epidemiologists in 2011. In follow up to reports of occupational exposures, CDC often provides technical assistance to state health departments to identify all persons with possible exposures, define level of risk, and provide recommendations for postexposure prophylaxis and health monitoring of exposed persons. RESULTS: During 2008-2013, BSPB provided technical assistance to 20 U.S. states and Puerto Rico involving 37 confirmed cases of melioidosis (34 human cases and three animal cases). Among those with documented travel history, the majority of reported cases (64%) occurred among persons with a documented travel history to areas endemic for melioidosis. Two persons did not report any travel outside of the United States. Separately, six incidents of possible occupational exposure involving research activities also were reported to BSPB, for which two incidents involved occupational exposures and no human infections occurred. Technical assistance was not required for these incidents because of risk-level (low or none) and appropriate onsite occupational safety response. Of the 261 persons at risk for occupational exposure to B. pseudomallei while performing laboratory diagnostics, 43 (16%) persons had high-risk exposures, 130 (50%) persons had low-risk exposures, and 88 (34%) persons were classified as having undetermined or unknown risk. INTERPRETATION: A small number of U.S. cases of melioidosis have been reported among persons with no travel history outside of the United States, whereas the majority of cases have occurred in persons with a travel history to areas endemic for melioidosis. If the number of travelers continues to increase in countries where the disease is endemic, the likelihood of identifying imported melioidosis cases in the United States might also increase. PUBLIC HEALTH ACTIONS: Reporting of melioidosis cases can improve the ability to monitor the incidence and prevalence of the disease in the United States. To improve prevention and control of melioidosis, CDC recommends that (1) physicians consider melioidosis in the differential diagnosis of patients with acute febrile illnesses, risk factors for melioidosis, and compatible travel or exposure history; (2) personnel at risk for occupational exposure (e.g., laboratory workers or researchers) follow proper safety practices, which includes using appropriate personal protective equipment when working with unknown pathogens; and (3) all possible occupational exposures to B. pseudomallei be reported voluntarily to BSPB.
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Burkholderia pseudomallei/aislamiento & purificación , Melioidosis/epidemiología , Melioidosis/veterinaria , Enfermedades Profesionales/epidemiología , Exposición Profesional/estadística & datos numéricos , Vigilancia de la Población , Investigadores , Adulto , Anciano , Anciano de 80 o más Años , Animales , Centers for Disease Control and Prevention, U.S. , Niño , Femenino , Humanos , Iguanas/microbiología , Macaca/microbiología , Masculino , Persona de Mediana Edad , Exposición Profesional/efectos adversos , Puerto Rico/epidemiología , Investigadores/estadística & datos numéricos , Medición de Riesgo , Factores de Riesgo , Viaje , Estados Unidos/epidemiología , Adulto JovenRESUMEN
BACKGROUND: Melioidosis results from infection with Burkholderia pseudomallei and is associated with case-fatality rates up to 40%. Early diagnosis and treatment with appropriate antimicrobials can improve survival rates. Fatal and nonfatal melioidosis cases were identified in Puerto Rico in 2010 and 2012, respectively, which prompted contact investigations to identify risk factors for infection and evaluate endemicity. METHODS: Questionnaires were administered and serum specimens were collected from coworkers, neighborhood contacts within 250 m of both patients' residences, and injection drug user (IDU) contacts of the 2012 patient. Serum specimens were tested for evidence of prior exposure to B. pseudomallei by indirect hemagglutination assay. Neighborhood seropositivity results guided soil sampling to isolate B. pseudomallei. RESULTS: Serum specimens were collected from contacts of the 2010 (n = 51) and 2012 (n = 60) patients, respectively. No coworkers had detectable anti-B. pseudomallei antibody, whereas seropositive results among neighborhood contacts was 5% (n = 2) for the 2010 patient and 23% (n = 12) for the 2012 patient, as well as 2 of 3 IDU contacts for the 2012 case. Factors significantly associated with seropositivity were having skin wounds, sores, or ulcers (odds ratio [OR], 4.6; 95% confidence interval [CI], 1.2-17.8) and IDU (OR, 18.0; 95% CI, 1.6-194.0). Burkholderia pseudomallei was isolated from soil collected in the neighborhood of the 2012 patient. CONCLUSIONS: Taken together, isolation of B. pseudomallei from a soil sample and high seropositivity among patient contacts suggest at least regional endemicity of melioidosis in Puerto Rico. Increased awareness of melioidosis is needed to enable early case identification and early initiation of appropriate antimicrobial therapy.