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1.
Commun Biol ; 7(1): 667, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38816486

RESUMEN

The Anopheles gambiae 1000 Genomes (Ag1000G) Consortium previously utilized deep sequencing methods to catalogue genetic diversity across African An. gambiae populations. We analyzed the complete datasets of 1142 individually sequenced mosquitoes through Microsoft Premonition's Bayesian mixture model based (BMM) metagenomics pipeline. All specimens were confirmed as either An. gambiae sensu stricto (s.s.) or An. coluzzii with a high degree of confidence ( > 98% identity to reference). Homo sapiens DNA was identified in all specimens indicating contamination may have occurred either at the time of specimen collection, preparation and/or sequencing. We found evidence of vertebrate hosts in 162 specimens. 59 specimens contained validated Plasmodium falciparum reads. Human hepatitis B and primate erythroparvovirus-1 viral sequences were identified in fifteen and three mosquito specimens, respectively. 478 of the 1,142 specimens were found to contain bacterial reads and bacteriophage-related contigs were detected in 27 specimens. This analysis demonstrates the capacity of metagenomic approaches to elucidate important vector-host-pathogen interactions of epidemiological significance.


Asunto(s)
Anopheles , Metagenómica , Animales , Anopheles/virología , Anopheles/genética , Metagenómica/métodos , Genoma de los Insectos , Mosquitos Vectores/virología , Mosquitos Vectores/genética , Humanos , Variación Genética , Plasmodium falciparum/genética , Metagenoma
2.
F1000Res ; 12: 330, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37842340

RESUMEN

Despite efforts to minimize the impacts of malaria and reduce the number of primary vectors, malaria has yet to be eliminated in Zambia. Understudied vector species may perpetuate malaria transmission in pre-elimination settings. Anopheles squamosus is one of the most abundantly caught mosquito species in southern Zambia and has previously been found with Plasmodium falciparum sporozoites, a causal agent of human malaria. This species may be a critical vector of malaria transmission, however, there is a lack of genetic information available for An. squamosus. We report the first genome data and the first complete mitogenome (Mt) sequence of An. squamosus. The sequence was extracted from one individual mosquito from the Chidakwa area in Macha, Zambia. The raw reads were obtained using Illumina Novaseq 6000 and assembled through NOVOplasty alignment with related species. The length of the An. squamosus Mt was 15,351 bp, with 77.9 % AT content. The closest match to the whole mitochondrial genome in the phylogenetic tree is the African malaria mosquito, Anopheles gambiae. Its genome data is available through National Center for Biotechnology Information (NCBI) Sequencing Reads Archive (SRA) with accession number SRR22114392. The mitochondrial genome was deposited in NCBI GenBank with the accession number OP776919. The ITS2 containing contig sequence was deposited in GenBank with the accession number OQ241725. Mitogenome annotation and a phylogenetic tree with related Anopheles mosquito species are provided.


Asunto(s)
Anopheles , Carcinoma de Células Escamosas , Genoma Mitocondrial , Malaria , Animales , Anopheles/genética , Genoma Mitocondrial/genética , Malaria/genética , Mosquitos Vectores/genética , Filogenia , Zambia
3.
Am J Trop Med Hyg ; 107(4_Suppl): 55-67, 2022 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-36228903

RESUMEN

For a decade, the Southern and Central Africa International Center of Excellence for Malaria Research has operated with local partners across study sites in Zambia and Zimbabwe that range from hypo- to holoendemic and vary ecologically and entomologically. The burden of malaria and the impact of control measures were assessed in longitudinal cohorts, cross-sectional surveys, passive and reactive case detection, and other observational designs that incorporated multidisciplinary scientific approaches: classical epidemiology, geospatial science, serosurveillance, parasite and mosquito genetics, and vector bionomics. Findings to date have helped elaborate the patterns and possible causes of sustained low-to-moderate transmission in southern Zambia and eastern Zimbabwe and recalcitrant high transmission and fatality in northern Zambia. Cryptic and novel mosquito vectors, asymptomatic parasite reservoirs in older children, residual parasitemia and gametocytemia after treatment, indoor residual spraying timed dyssynchronously to vector abundance, and stockouts of essential malaria commodities, all in the context of intractable rural poverty, appear to explain the persistent malaria burden despite current interventions. Ongoing studies of high-resolution transmission chains, parasite population structures, long-term malaria periodicity, and molecular entomology are further helping to lay new avenues for malaria control in southern and central Africa and similar settings.


Asunto(s)
Insecticidas , Malaria , Parásitos , África Central , Animales , Niño , Estudios Transversales , Humanos , Malaria/epidemiología , Malaria/prevención & control , Control de Mosquitos , Zambia/epidemiología , Zimbabwe/epidemiología
4.
Am J Trop Med Hyg ; 107(4_Suppl): 68-74, 2022 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-36228913

RESUMEN

The International Centers of Excellence for Malaria Research (ICEMR) were established by the National Institute of Allergy and Infectious Diseases more than a decade ago to provide multidisciplinary research support to malaria control programs worldwide, operating in endemic areas and contributing technology, expertise, and ultimately policy guidance for malaria control and elimination. The Southern and Central Africa ICEMR has conducted research across three main sites in Zambia and Zimbabwe that differ in ecology, entomology, transmission intensity, and control strategies. Scientific findings led to new policies and action by the national malaria control programs and their partners in the selection of methods, materials, timing, and locations of case management and vector control. Malaria risk maps and predictive models of case detection furnished by the ICEMR informed malaria elimination programming in southern Zambia, and time series analyses of entomological and parasitological data motivated several major changes to indoor residual spray campaigns in northern Zambia. Along the Zimbabwe-Mozambique border, temporal and geospatial data are currently informing investigations into a recent resurgence of malaria. Other ICEMR findings pertaining to parasite and mosquito genetics, human behavior, and clinical epidemiology have similarly yielded immediate and long-term policy implications at each of the sites, often with generalizable conclusions. The ICEMR programs thereby provide rigorous scientific investigations and analyses to national control and elimination programs, without which the impediments to malaria control and their potential solutions would remain understudied.


Asunto(s)
Malaria , Mosquitos Vectores , África Central , Animales , Humanos , Malaria/epidemiología , Malaria/prevención & control , Control de Mosquitos/métodos , Políticas , Zambia/epidemiología , Zimbabwe/epidemiología
5.
Malar J ; 21(1): 211, 2022 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-35780113

RESUMEN

BACKGROUND: Nchelenge District in northern Zambia suffers from holoendemic malaria transmission despite a decade of yearly indoor residual spraying (IRS) and insecticide-treated net (ITN) distributions. One hypothesis for this lack of impact is that some vectors in the area may forage in the early evening or outdoors. Anopheles gibbinsi specimens were identified in early evening mosquito collections performed in this study area, and further insight was gleaned into this taxon, including characterizing its genetic identity, feeding preferences, and potential role as a malaria vector. METHODS: Mosquitoes were collected in July and August 2019 by CDC light traps in Nchelenge District in indoor sitting rooms, outdoor gathering spaces, and animal pens from 16:00-22:00. Host detection by PCR, COI and ITS2 PCR, and circumsporozoite (CSP) ELISA were performed on all samples morphologically identified as An. gibbinsi, and a subset of specimens were selected for COI and ITS2 sequencing. To determine risk factors for increased abundance of An. gibbinsi, a negative binomial generalized linear mixed-effects model was performed with household-level variables of interest. RESULTS: Comparison of COI and ITS2 An. gibbinsi reference sequences to the NCBI database revealed > 99% identity to "Anopheles sp. 6" from Kenya. More than 97% of specimens were morphologically and molecularly consistent with An. gibbinsi. Specimens were primarily collected in animal pen traps (59.2%), followed by traps outdoors near where humans gather (24.3%), and traps set indoors (16.5%). Host DNA detection revealed a high propensity for goats, but 5% of specimens with detected host DNA had fed on humans. No specimens were positive for Plasmodium falciparum sporozoites. Animal pens and inland households > 3 km from Lake Mweru were both associated with increased An. gibbinsi abundance. CONCLUSIONS: This is the first report of An. gibbinsi in Nchelenge District, Zambia. This study provided a species identity for unknown "An. sp. 6" in the NCBI database, which has been implicated in malaria transmission in Kenya. Composite data suggest that this species is largely zoophilic and exophilic, but comes into contact with humans and the malaria parasites they carry. This species should continue to be monitored in Zambia and neighbouring countries as a potential malaria vector.


Asunto(s)
Anopheles , Malaria , Animales , Anopheles/parasitología , ADN , Malaria/epidemiología , Mosquitos Vectores/parasitología , Zambia/epidemiología
6.
Am J Trop Med Hyg ; 2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35344932

RESUMEN

Malaria transmission has declined substantially in Southern Province, Zambia, which is considered a low-transmission setting. The Zambian government introduced a reactive test-and-treat strategy to identify active zones of transmission and treat parasitemic residents. This study was conducted in the Choma District, Southern Province, Zambia, concurrently with an evaluation of this strategy to identify vectors responsible for sustaining transmission, and to identify entomological, spatial, and ecological risk factors associated with increased densities of mosquitoes. Anophelines were collected with CDC light traps indoors and near animal pens in index cases and neighboring households. Outdoor collections captured significantly more anophelines than indoor traps, and 10 different anopheline species were identified. Four species (Anopheles arabiensis, An. rufipes, An. squamosus, and An. coustani) were positive for Plasmodium falciparum circumsporozoite protein by ELISA, and 61% of these 26 anophelines were captured outdoors. Bloodmeal assays confirm plasticity in An. arabiensis foraging, feeding both on humans and animals, whereas An. rufipes, An. squamosus, and An. coustani were largely zoophilic and exophilic. Linear regression of count data for indoor traps revealed that households with at least one parasitemic resident by polymerase chain reaction testing was associated with higher female anopheline counts. This suggests that targeting households with parasitemic individuals for vector interventions may reduce indoor anopheline populations. However, many vectors species responsible for transmission may not be affected by indoor interventions because they are primarily exophilic and forage opportunistically. These data underscore the necessity for further evaluation of vector surveillance and control tools that are effective outdoors, in conjunction with current indoor-based interventions.

7.
Artículo en Inglés | MEDLINE | ID: mdl-35983564

RESUMEN

Residual vector populations that do not come in contact with the most frequently utilized indoor-directed interventions present major challenges to global malaria eradication. Many of these residual populations are mosquito species about which little is known. As part of a study to assess the threat of outdoor exposure to malaria mosquitoes within the Southern and Central Africa International Centers of Excellence for Malaria Research, foraging female anophelines were collected outside households in Nchelenge District, northern Zambia. These anophelines proved to be more diverse than had previously been reported in the area. In order to further characterize the anopheline species, sequencing and phylogenetic approaches were utilized. Anopheline mosquitoes were collected from outdoor light traps, morphologically identified, and sent to Johns Hopkins Bloomberg School of Public Health for sequencing. Sanger sequencing from 115 field-derived samples yielded mitochondrial COI sequences, which were aligned with a homologous 488 bp gene segment from known anophelines (n = 140) retrieved from NCBI. Nuclear ITS2 sequences (n = 57) for at least one individual from each unique COI clade were generated and compared against NCBI's nucleotide BLAST database to provide additional evidence for taxonomical identity and structure. Molecular and morphological data were combined for assignment of species or higher taxonomy. Twelve phylogenetic groups were characterized from the COI and ITS2 sequence data, including the primary vector species Anopheles funestus s.s. and An. gambiae s.s. An unexpectedly large proportion of the field collections were identified as An. coustani and An. sp. 6. Six phylogenetic groups remain unidentified to species-level. Outdoor collections of anopheline mosquitoes in areas frequented by people in Nchelenge, northern Zambia, proved to be extremely diverse. Morphological misidentification and underrepresentation of some anopheline species in sequence databases confound efforts to confirm identity of potential malaria vector species. The large number of unidentified anophelines could compromise the malaria vector surveillance and malaria control efforts not only in northern Zambia but other places where surveillance and control are focused on indoor-foraging and resting anophelines. Therefore, it is critical to continue development of methodologies that allow better identification of these populations and revisiting and cleaning current genomic databases.

8.
PLoS One ; 15(6): e0231061, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32525960

RESUMEN

Monitoring the presence and spread of pathogens in the environment is of critical importance. Rapid detection of infectious disease outbreaks and prediction of their spread can facilitate early responses of health agencies and reduce the severity of outbreaks. Current sampling methods are sorely limited by available personnel and throughput. For instance, xenosurveillance utilizes captured arthropod vectors, such as mosquitoes, as sampling tools to access blood from a wide variety of vertebrate hosts. Next generation sequencing (NGS) of nucleic acid from individual blooded mosquitoes can be used to identify mosquito and host species, and microorganisms including pathogens circulating within either host. However, there are practical challenges to collecting and processing mosquitoes for xenosurveillance, such as the rapid metabolization or decay of microorganisms within the mosquito midgut. This particularly affects pathogens that do not replicate in mosquitoes, preventing their detection by NGS or other methods. Accordingly, we performed a series of experiments to establish the windows of detection for DNA or RNA from human blood and/or viruses present in mosquito blood meals. Our results will contribute to the development of xenosurveillance techniques with respect to optimal timing of sample collection and NGS processing and will also aid trap design by demonstrating the stabilizing effect of temperature control on viral genome recovery from blood-fed mosquitoes.


Asunto(s)
Sangre , Culicidae/virología , ADN Viral/análisis , ARN Viral/análisis , Animales , ADN Viral/genética , Monitoreo del Ambiente , Humanos , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa
9.
Malar J ; 18(1): 400, 2019 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-31801548

RESUMEN

BACKGROUND: While the utility of parasite genotyping for malaria elimination has been extensively documented in low to moderate transmission settings, it has been less well-characterized in holoendemic regions. High malaria burden settings have received renewed attention acknowledging their critical role in malaria elimination. Defining the role for parasite genomics in driving these high burden settings towards elimination will enhance future control programme planning. METHODS: Amplicon deep sequencing was used to characterize parasite population genetic diversity at polymorphic Plasmodium falciparum loci, Pfama1 and Pfcsp, at two timepoints in June-July 2016 and January-March 2017 in a high transmission region along the international border between Luapula Province, Zambia and Haut-Katanga Province, the Democratic Republic of the Congo (DRC). RESULTS: High genetic diversity was observed across both seasons and in both countries. No evidence of population structure was observed between parasite populations on either side of the border, suggesting that this region may be one contiguous transmission zone. Despite a decline in parasite prevalence at the sampling locations in Haut-Katanga Province, no genetic signatures of a population bottleneck were detected, suggesting that larger declines in transmission may be required to reduce parasite genetic diversity. Analysing rare variants may be a suitable alternative approach for detecting epidemiologically important genetic signatures in highly diverse populations; however, the challenge is distinguishing true signals from potential artifacts introduced by small sample sizes. CONCLUSIONS: Continuing to explore and document the utility of various parasite genotyping approaches for understanding malaria transmission in holoendemic settings will be valuable to future control and elimination programmes, empowering evidence-based selection of tools and methods to address pertinent questions, thus enabling more efficient resource allocation.


Asunto(s)
Variación Genética , Malaria Falciparum/prevención & control , Plasmodium falciparum/genética , República Democrática del Congo/epidemiología , Malaria Falciparum/epidemiología , Estaciones del Año , Zambia/epidemiología
10.
Front Plant Sci ; 6: 356, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26042141

RESUMEN

Lentil (Lens culinaris Medik), a nutritious traditional pulse crop, has been experiencing a declining area of production in South East Asia, due to lower yields, and marginal soils. The objective of this study was to determine whether selenium (Se) fertilization can increase lentil yield, productivity, and seed quality (both seed Se concentration and speciation). Selenium was provided to five lentil accessions as selenate or selenite by foliar or soil application at rates of 0, 10, 20, or 30 kg Se/ha and the resulting lentil biomass, grain yield, seed Se concentration, and Se speciation was determined. Seed Se concentration was measured using inductively coupled plasma optical emission spectrometry (ICP-OES) after acid digestion. Seed Se speciation was measured using ICP-mass spectrometry with a high performance liquid chromatography (ICP-MS-LC) system. Foliar application of Se significantly increased lentil biomass (5586 vs. 7361 kg/ha), grain yield (1732 vs. 2468 kg /ha), and seed Se concentrations (0.8 vs. 2.4 µg/g) compared to soil application. In general, both application methods and both forms of Se increased concentrations of organic Se forms (selenocysteine and selenomethionine) in lentil seeds. Not surprisingly, the high yielding CDC Redberry had the highest levels of biomass and grain yield of all varieties evaluated. Eston, ILL505, and CDC Robin had the greatest responses to Se fertilization with respect to both grain yield, seed Se concentration and speciation; thus, use of these varieties in areas with low-Se soils might require Se fertilization to reach yield potentials.

11.
Rehabil Nurs ; 36(1): 3-12, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21290959

RESUMEN

From the moment an adolescent with acquired brain injury (ABI) is admitted to the hospital, his or her caregiver develops hopes for the recovery and future of the patient; however, rehabilitation nurses have reported that these hopes are not always congruent with the nurse's observations of the adolescent's progression. The purpose of this study was threefold: (1) explore the caregiver's hope for recovery of his or her family member who has experienced an ABI, (2) compare the nurse's hopes for the patient with ABI to those of the caregiver, and (3) identify what caregivers and nurses do to maintain hope for recovery during the rehabilitation process. This qualitative study validated that in some cases there was a disconnect between caregivers' and nurses' hopes for recovery. Four themes related to the caregiver's maintenance of hope were identified: "the importance of family," "taking one day at a time," "knowing the patient better," and "spiritual strength brings me through." Enhancing the perceptual congruence between nurse and caregiver hope during rehabilitation will ultimately improve patient outcomes.


Asunto(s)
Lesiones Encefálicas/enfermería , Lesiones Encefálicas/rehabilitación , Cuidadores/psicología , Motivación , Relaciones Profesional-Familia , Recuperación de la Función , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermería en Rehabilitación , Sudeste de Estados Unidos , Espiritualidad
12.
Nurs Educ Perspect ; 30(4): 245-8, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19753859

RESUMEN

As the United States population ages, it is important that nursing faculty adequately prepare undergraduate students to provide optimal nursing care for older adults. By 2030, estimates are that one in five Americans will be over the age of 65. Older adults often have complex health issues and use more health care resources than other age groups. Over the last 10 years, schools of nursing have been increasingly enhancing the gerontological content in their curricula. However, to ensure that nurses will have the specialized geriatric knowledge and skills to improve health outcomes, expansion and enhancement of geriatric curricula must be an ongoing process. This article presents information regarding the process that one university used to evaluate and revise its curriculum using geriatric competences and recommendations set forth by the Hartford Foundation and AACN.


Asunto(s)
Curriculum , Bachillerato en Enfermería , Enfermería Geriátrica/educación , Geriatría , Facultades de Enfermería , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Georgia , Evaluación Geriátrica , Humanos , Relaciones Enfermero-Paciente
13.
Res Nurs Health ; 32(6): 592-605, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19722169

RESUMEN

Evaluating factors that reduce stroke survivors' (SS) health-related quality of life (HRQOL) is important for developing interventions to improve HRQOL after stroke. The influence of baseline caregiver and family characteristics (physical health, depressive symptoms, family communication) on five domains of SS HRQOL (physical function, memory/thinking, social activities, communication, and mood) was examined. Data were collected on 132 SS-caregiver dyads at baseline, 4 months, and 12 months. Baseline caregiver depressive symptoms predicted lower scores for SS physical function and communication at 4 months and social participation and mood at 12 months. Male caregiver gender was negatively associated with SS HRQOL (communication and mood) at 12 months. Early intervention targeting these family characteristics, especially caregiver depressive symptoms, may improve survivors' HRQOL.


Asunto(s)
Cuidadores/psicología , Salud de la Familia , Calidad de Vida , Accidente Cerebrovascular/enfermería , Accidente Cerebrovascular/psicología , Sobrevivientes/psicología , Adulto , Afecto , Anciano , Anciano de 80 o más Años , Depresión , Emociones , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Análisis de Regresión , Encuestas y Cuestionarios
14.
J Neurosci Nurs ; 39(3): 190-1, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17591415

RESUMEN

There are many rehabilitation teams and rehabilitation consultants. The team presented here involved the unique collaboration of university nursing scholars and clinicians from a local rehabilitation hospital. The melding of these two groups is providing new opportunities for staff nurses, administrators, and faculty members to work together and use nursing research to provide the base of evidence necessary to enhance rehabilitation nursing knowledge in the brain injury setting.


Asunto(s)
Lesiones Encefálicas/rehabilitación , Difusión de Innovaciones , Medicina Basada en la Evidencia/organización & administración , Docentes de Enfermería/organización & administración , Rol de la Enfermera , Investigación en Enfermería/organización & administración , Actitud del Personal de Salud , Benchmarking , Conducta Cooperativa , Medicina Basada en la Evidencia/educación , Conocimientos, Actitudes y Práctica en Salud , Humanos , Relaciones Interprofesionales , Enfermeras Clínicas/organización & administración , Rol de la Enfermera/psicología , Investigación en Enfermería/educación , Personal de Enfermería en Hospital/educación , Personal de Enfermería en Hospital/psicología , Centros de Rehabilitación
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