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4.
Ecol Lett ; 24(4): 829-846, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33501751

RESUMEN

Vector-borne diseases (VBDs) are embedded within complex socio-ecological systems. While research has traditionally focused on the direct effects of VBDs on human morbidity and mortality, it is increasingly clear that their impacts are much more pervasive. VBDs are dynamically linked to feedbacks between environmental conditions, vector ecology, disease burden, and societal responses that drive transmission. As a result, VBDs have had profound influence on human history. Mechanisms include: (1) killing or debilitating large numbers of people, with demographic and population-level impacts; (2) differentially affecting populations based on prior history of disease exposure, immunity, and resistance; (3) being weaponised to promote or justify hierarchies of power, colonialism, racism, classism and sexism; (4) catalysing changes in ideas, institutions, infrastructure, technologies and social practices in efforts to control disease outbreaks; and (5) changing human relationships with the land and environment. We use historical and archaeological evidence interpreted through an ecological lens to illustrate how VBDs have shaped society and culture, focusing on case studies from four pertinent VBDs: plague, malaria, yellow fever and trypanosomiasis. By comparing across diseases, time periods and geographies, we highlight the enormous scope and variety of mechanisms by which VBDs have influenced human history.


Asunto(s)
Malaria , Enfermedades Transmitidas por Vectores , Vectores de Enfermedades , Humanos
5.
Environ Sci Technol ; 55(1): 478-487, 2021 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-33322894

RESUMEN

The California state government put restrictions on outdoor residential water use, including landscape irrigation, during the 2012-2016 drought. The public health implications of these actions are largely unknown, particularly with respect to mosquito-borne disease transmission. While residential irrigation facilitates persistence of mosquitoes by increasing the availability of standing water, few studies have investigated its effects on vector abundance. In two study sub-regions in the Los Angeles Basin, we examined the effect of outdoor residential water use restrictions on the abundance of the most important regional West Nile virus vector, Culex quinquefasciatus. Using spatiotemporal random forest models fit to Cx. abundance during drought and non-drought years, we generated counterfactual estimates of Cx. abundance under a hypothetical drought scenario without water use restrictions. We estimate that Cx. abundance would have been 44% and 39% larger in West Los Angeles and Orange counties, respectively, if outdoor water usage had remained unchanged. Our results suggest that drought, without mandatory water use restrictions, may counterintuitively increase the availability of larval habitats for vectors in naturally dry, highly irrigated settings and such mandatory water use restrictions may constrain Cx. abundance, which could reduce the risk of mosquito-borne disease while helping urban utilities maintain adequate water supplies.


Asunto(s)
Culex , Agua , Animales , California , Vectores de Enfermedades , Sequías , Los Angeles , Mosquitos Vectores
6.
Bull Entomol Res ; 111(2): 246-256, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33355061

RESUMEN

The meadow spittlebug, Philaenus spumarius (L.) (Hemiptera: Aphrophoridae), is the main vector in Europe of the recently detected plant pathogen bacterium Xylella fastidiosa Wells et al. (Xanthomonadales: Xanthomonadaceae). While the ecology of continental populations is well documented, nothing is known about the insular populations of P. spumarius, such as in Corsica, where the bacterium was detected in 2015. Hence, in an epidemiological context, the ecology of P. spumarius has been studied in a maquis landscape in the Ajaccio region between 2017 and 2019. Adults and nymphs were almost exclusively collected on Cistus monspeliensis L. (Cistaceae). However, very few specimens were collected in summer, suggesting a movement of the adults to sheltered habitats. Unfortunately, despite several trapping methods used, the location of adult summer habitat remains unknown for the studied population. It might be tempting to destroy the central plant host of P. spumarius populations. However, as spittlebug nymphs are highly polyphagous on low-growing plant species and as the females can lay eggs in any dead plant tissues, such practice could have limited the impact. Instead, the strong relationship between P. spumarius and C. monspeliensis could be used to monitor spittlebug populations, to limit/concentrate the means of insect control, or in an agronomic context to lure insects away from crops. Maintaining natural arboreal vegetation around agronomic systems could help decrease insect abundance - and potentially, pathogen load - on cultivated species. Such hypotheses need to be further studied by landscape experiments.


Asunto(s)
Conducta Alimentaria , Hemípteros/fisiología , Animales , Cistus , Productos Agrícolas/microbiología , Vectores de Enfermedades , Seguimiento de Parámetros Ecológicos , Ecosistema , Francia/epidemiología , Hemípteros/microbiología , Hiperfagia , Insectos Vectores/microbiología , Insectos Vectores/fisiología , Ninfa/fisiología , Control de Plagas/tendencias , Enfermedades de las Plantas/microbiología , Estaciones del Año , Especificidad de la Especie
7.
Viruses ; 12(12)2020 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-33348905

RESUMEN

Plant viruses are commonly vectored by flying or crawling animals, such as aphids and beetles, and cause serious losses in major agricultural and horticultural crops. Controlling virus spread is often achieved by minimizing a crop's exposure to the vector, or by reducing vector numbers with compounds such as insecticides. A major, but less obvious, factor not controlled by these measures is Homo sapiens. Here, we discuss the inconvenient truth of how humans have become superspreaders of plant viruses on both a local and a global scale.


Asunto(s)
Productos Agrícolas/virología , Enfermedades de las Plantas/virología , Virosis/transmisión , Animales , Cambio Climático , Vectores de Enfermedades , Humanos , Enfermedades de las Plantas/prevención & control , Virus de Plantas/crecimiento & desarrollo
8.
Ned Tijdschr Geneeskd ; 1642020 12 03.
Artículo en Holandés | MEDLINE | ID: mdl-33332041

RESUMEN

The plague epidemics wiped out large parts of the city population from the 15th to the 17th century in the Netherlands. The plague bacterium (Yersinia pestis) is transmitted to humans through infected rats and fleas and has been transferred from China to Europe via the trade routes over land and sea. Meetings were banned, plague victims were isolated at home or in pest houses, and ships quarantined. In the densely populated, poor neighborhoods of the cities, however, isolation and keeping distance were not feasible, which allowed the plague to rapidly spread. The lessons we have learned from the plague epidemics are timeless. Isolation, keeping your distance and quarantine were key principles and now apply again in the approach to the current Covid-19 pandemic. How effective these measures are depends on the social context in which they are applied.


Asunto(s)
Pandemias , Peste , Cuarentena , Animales , /prevención & control , Reservorios de Enfermedades , Transmisión de Enfermedad Infecciosa/prevención & control , Vectores de Enfermedades , Historia del Siglo XV , Historia del Siglo XVI , Historia del Siglo XVII , Humanos , Países Bajos/epidemiología , Pandemias/historia , Pandemias/prevención & control , Peste/epidemiología , Peste/historia , Peste/microbiología , Peste/prevención & control , Cuarentena/historia , Cuarentena/métodos , Yersinia pestis/patogenicidad
9.
Onderstepoort J Vet Res ; 87(1): e1-e9, 2020 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-33354975

RESUMEN

The first known severe disease caused by a coronavirus (CoV) in humans emerged with the severe acute respiratory syndrome (SARS) epidemic in China, which killed 774 people during its 2002/2003 outbreak. The Middle East respiratory syndrome (MERS) was the second human fatal disease, which started in 2012 in Saudi Arabia and resulted in 858 fatalities. In December 2019, a new virus, SARS-CoV-2 (COVID-19), originating from China, began generating headlines worldwide because of the unprecedented speed of its transmission; 5.2 million people were infected and 338 480 had been reported dead from December 2019 to May 2020. These human coronaviruses are believed to have an animal origin and had reached humans through species jump. Coronaviruses are well known for their high frequency of recombination and high mutation rates, allowing them to adapt to new hosts and ecological niches. This review summarises existing information on what is currently known on the role of wild and domesticated animals and discussions on whether they are the natural reservoir/amplifiers hosts or incidental hosts of CoVs. Results of experimental infection and transmission using different wild, domesticated and pet animals are also reviewed. The need for a One Health approach in implementing measures and practices is highlighted to improve human health and reduce the emergence of pandemics from these zoonotic viruses.


Asunto(s)
/epidemiología , Infecciones por Coronavirus/epidemiología , Coronavirus del Síndrome Respiratorio de Oriente Medio , Zoonosis , Animales , /transmisión , Camelus/virología , Quirópteros/virología , Infecciones por Coronavirus/etiología , Infecciones por Coronavirus/transmisión , Vectores de Enfermedades , Salud Global , Humanos , Salud Única , Pandemias
10.
PLoS Genet ; 16(12): e1009170, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33326438

RESUMEN

Analysis of genetic polymorphism is a powerful tool for epidemiological surveillance and research. Powerful inference from pathogen genetic variation, however, is often restrained by limited access to representative target DNA, especially in the study of obligate parasitic species for which ex vivo culture is resource-intensive or bias-prone. Modern sequence capture methods enable pathogen genetic variation to be analyzed directly from host/vector material but are often too complex and expensive for resource-poor settings where infectious diseases prevail. This study proposes a simple, cost-effective 'genome-wide locus sequence typing' (GLST) tool based on massive parallel amplification of information hotspots throughout the target pathogen genome. The multiplexed polymerase chain reaction amplifies hundreds of different, user-defined genetic targets in a single reaction tube, and subsequent agarose gel-based clean-up and barcoding completes library preparation at under 4 USD per sample. Our study generates a flexible GLST primer panel design workflow for Trypanosoma cruzi, the parasitic agent of Chagas disease. We successfully apply our 203-target GLST panel to direct, culture-free metagenomic extracts from triatomine vectors containing a minimum of 3.69 pg/µl T. cruzi DNA and further elaborate on method performance by sequencing GLST libraries from T. cruzi reference clones representing discrete typing units (DTUs) TcI, TcIII, TcIV, TcV and TcVI. The 780 SNP sites we identify in the sample set repeatably distinguish parasites infecting sympatric vectors and detect correlations between genetic and geographic distances at regional (< 150 km) as well as continental scales. The markers also clearly separate TcI, TcIII, TcIV and TcV + TcVI and appear to distinguish multiclonal infections within TcI. We discuss the advantages, limitations and prospects of our method across a spectrum of epidemiological research.


Asunto(s)
Código de Barras del ADN Taxonómico/métodos , Genoma de Protozoos , Metagenoma , Metagenómica/métodos , Trypanosoma cruzi/genética , Secuenciación Completa del Genoma/métodos , Animales , Costos y Análisis de Costo , Código de Barras del ADN Taxonómico/economía , Código de Barras del ADN Taxonómico/normas , Vectores de Enfermedades , Hemípteros/parasitología , Metagenómica/economía , Metagenómica/normas , Polimorfismo Genético , Trypanosoma cruzi/patogenicidad , Virulencia/genética , Secuenciación Completa del Genoma/economía , Secuenciación Completa del Genoma/normas
11.
PLoS Pathog ; 16(12): e1009068, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33382858

RESUMEN

Originating from African forests, Zika virus (ZIKV) has now emerged worldwide in urbanized areas, mainly transmitted by Aedes aegypti mosquitoes. Although Aedes albopictus can transmit ZIKV experimentally and was suspected to be a ZIKV vector in Central Africa, the potential of this species to sustain virus transmission was yet to be uncovered until the end of 2019, when several autochthonous transmissions of the virus vectored by Ae. albopictus occurred in France. Aside from these few locally acquired ZIKV infections, most territories colonized by Ae. albopictus have been spared so far. The risk level of ZIKV emergence in these areas remains however an open question. To assess Ae. albopictus' vector potential for ZIKV and identify key virus outbreak predictors, we built a complete framework using the complementary combination of (i) dose-dependent experimental Ae. albopictus exposure to ZIKV followed by time-dependent assessment of infection and systemic infection rates, (ii) modeling of intra-human ZIKV viremia dynamics, and (iii) in silico epidemiological simulations using an Agent-Based Model. The highest risk of transmission occurred during the pre-symptomatic stage of the disease, at the peak of viremia. At this dose, mosquito infection probability was estimated to be 20%, and 21 days were required to reach the median systemic infection rates. Mosquito population origin, either temperate or tropical, had no impact on infection rates or intra-host virus dynamic. Despite these unfavorable characteristics for transmission, Ae. albopictus was still able to trigger and yield large outbreaks in a simulated environment in the presence of sufficiently high mosquito biting rates. Our results reveal a low but existing epidemic potential of Ae. albopictus for ZIKV, that might explain the absence of large scale ZIKV epidemics so far in territories occupied only by Ae. albopictus. They nevertheless support active surveillance and eradication programs in these territories to maintain the risk of emergence to a low level.


Asunto(s)
Mosquitos Vectores/metabolismo , Mosquitos Vectores/virología , Infección por el Virus Zika/transmisión , Aedes/metabolismo , Aedes/virología , Animales , Brotes de Enfermedades , Vectores de Enfermedades , Epidemias , Humanos , Modelos Teóricos , Saliva/virología , Carga Viral , Viremia/transmisión , Virus Zika/patogenicidad , Infección por el Virus Zika/epidemiología , Infección por el Virus Zika/virología
12.
Viruses ; 12(12)2020 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-33339336

RESUMEN

Using molecular techniques and bioinformatics tools, we studied the vector-host interactions and the molecular epidemiology of West Nile virus (WNV) in western Iran. Mosquitoes were collected during 2017 and 2018. DNA typing assays were used to study vector-host interactions. Mosquitoes were screened by RT-PCR for the genomes of five virus families. WNV-positive samples were fully sequenced and evolutionary tree and molecular architecture were constructed by Geneious software and SWISS-MODEL workspace, respectively. A total of 5028 mosquito specimens were collected and identified. The most prevalent species was Culex (Cx.) pipiens complex (57.3%). Analysis of the blood-feeding preferences of blood-fed mosquitoes revealed six mammalian and one bird species as hosts. One mosquito pool containing non-blood-fed Cx. theileri and one blood-fed Culex pipiens pipiens (Cpp.) biotype pipiens were positive for WNV. A phylogram indicated that the obtained WNV sequences belonged to lineage 2, subclade 2 g. Several amino acid substitutions suspected as virulence markers were observed in the Iranian WNV strains. The three-dimensional structural homology model of the E-protein identified hot spot domains known to facilitate virus invasion and neurotropism. The recent detection of WNV lineage 2 in mosquitoes from several regions of Iran in consecutive years suggests that the virus is established in the country.


Asunto(s)
Vectores de Enfermedades , Interacciones Huésped-Patógeno , Fiebre del Nilo Occidental/transmisión , Fiebre del Nilo Occidental/virología , Virus del Nilo Occidental/fisiología , Secuencia de Aminoácidos , Animales , Evolución Molecular , Genoma Viral , Genómica/métodos , Geografía Médica , Humanos , Irán/epidemiología , Mosquitos Vectores/virología , Filogenia , Dinámica Poblacional , Prevalencia , Conformación Proteica , Proteínas Estructurales Virales/química , Proteínas Estructurales Virales/metabolismo , Virulencia , Factores de Virulencia , Secuenciación Completa del Genoma
13.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(12): 1838-1842, 2020 Dec 30.
Artículo en Chino | MEDLINE | ID: mdl-33380405

RESUMEN

Coronavirus disease 2019 (COVID-19) pandemic has caused a total of 55 928 327 confirmed cases and 1 344 003 deaths as of November 19, 2020. But so far the origin of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes this pandemic has remained undetermined. The purpose of this study is to review the current research of SARS-CoV-2 and the existing problems therein, which may provide inspiration for further researches. Existing evidence suggested that SARS-CoV-2 may be derived from bat coronavirus 40-70 years ago. During the evolution, this virus underwent extensive variations in the process of mutations and natural selection. Different genomic regions of SARS-CoV-2 may have different selection pressures, but all of which increase the difficulty of tracing the origin of this virus. A wide variety of animals have been considered as potential hosts of SARS-CoV-2, including cats, lions, tigers, dogs and minks. SARS-CoV-2 has a chance to transmit from humans to animals and can be transmitted among animals. Current research evidence has shown that China is not the original source of SARS-CoV-2. It is still unclear how the virus spreads to human, and efforts are still need to be made to explore the origin of SARS-CoV-2, its hosts and intermediate hosts, and the mechanism of its transmission across different species of animals.


Asunto(s)
/transmisión , Quirópteros/virología , /clasificación , Animales , Gatos , China , Vectores de Enfermedades , Perros , Evolución Molecular , Humanos
15.
Korean J Parasitol ; 58(5): 583-587, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33202512

RESUMEN

Blastocystis sp. is a kind of protozoa living in the intestinal tract of human and animals, which will cause intestinal diseases such as diarrhea, abdominal distension and vomiting. This paper was aimed to understand the infection of Blastocystis sp. In golden monkeys and the transmission path in North China. Thirty-seven feces samples from golden monkeys and 116 cockroach samples from Shijiazhuang Zoo were collected from July to October 2019 for PCR analysis of Blastocystis sp. Genetic diversity analysis was further conducted on the samples with positive PCR results. The results showed that the infection rate was 48.7% (18/37) in golden monkeys and 82.8% (96/116) in cockroaches, respectively. The genetic evolution analysis based on small subunit ribosomal RNA demonstrated that three subtypes (ST) of Blastocystis sp. including ST1, ST2, and ST3 existed in the intestinal tract of golden monkeys, while only ST2 was detected in the intestinal tract of cockroaches. This paper may provide supports for the quarantine and control of Blastocystis sp. for the zoo in Northern China.


Asunto(s)
Animales de Zoológico , Infecciones por Blastocystis/transmisión , Infecciones por Blastocystis/veterinaria , Blastocystis/aislamiento & purificación , Cucarachas/parasitología , Vectores de Enfermedades , Insectos Vectores , Enfermedades de los Monos/parasitología , Enfermedades de los Monos/transmisión , Enfermedades Parasitarias en Animales/parasitología , Enfermedades Parasitarias en Animales/transmisión , Animales , Blastocystis/clasificación , Blastocystis/genética , Infecciones por Blastocystis/epidemiología , Infecciones por Blastocystis/parasitología , Cercopithecus , China/epidemiología , Heces/parasitología , Femenino , Masculino , Enfermedades de los Monos/epidemiología , Enfermedades Parasitarias en Animales/epidemiología , Reacción en Cadena de la Polimerasa
16.
Rev Sci Tech ; 39(2): 407-415, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33046934

RESUMEN

In 2018, Cape Town, South Africa, nearly ran out of water. That this has not yet happened is in large part due to the water-saving efforts of its citizens. It is highly likely that this situation will be repeated in Cape Town and that similar situations will be experienced by major cities in other parts of the world. Efforts to save water should thus continue and the lessons learned in Cape Town should be shared. The functioning of Veterinary Services during a drought is affected in the same way as any business, in terms of running an office, but veterinary professionals face an increased risk of exposure to pathogens, compared to that of many occupations, and of veterinary officials becoming disease vectors. One component of Veterinary Services is veterinary laboratory services. Laboratory procedures rely heavily on water and, without advance planning, a laboratory's function can be severely limited by a restricted water supply. In many cases, innovative water-saving techniques can be used to reduce water use substantially without compromising the quality of the services offered. Here, the authors share their experiences and some lessons learned while working in Veterinary Services in the Western Cape province of South Africa.


Asunto(s)
Vectores de Enfermedades , Sequías , Animales , Ciudades , Sudáfrica
17.
Rev Soc Bras Med Trop ; 53: e20200335, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33111913

RESUMEN

INTRODUCTION: Schistosomiasis, caused by infection from Schistosoma mansoni, is a disease that represents an important public health problem for Brazil, especially for states in the Northeast region. Thus, the aim of this study is to present a new epidemiological profile for the disease in a municipality with low prevalence in the state of Alagoas, Brazil. METHODS: A cross-sectional study was conducted through a coproparasitological and malacological survey. A structured questionnaire was applied to the study participants to survey possible risk factors and a spatial analysis (kernel density) was used to measure the risk of infection. RESULTS: Of the 347 participants, 106 (30.5%) were infected by Schistosoma mansoni, most of them from the urban area of the municipality (68.9%; 73/106). A 3-fold risk of infection was found for individuals living in the urban area and a risk of 2.15 times for self-declared farmers. Biomphalaria glabrata and B. straminea were the species found in the municipality, but no animals were diagnosed as infected by the parasite. Spatial analysis showed a random distribution of vectors and human cases of the disease, and the formation of two clusters of human cases in the urban area was seen. CONCLUSIONS: A new epidemiological profile for schistosomiasis from S. mansoni infection was presented in a municipality of low endemicity: a high proportion of positive individuals in the urban area; presence of snails without positive diagnosis for S. mansoni infection; random distribution of vectors and human cases; and absence of association between classical risk factors and human infection.


Asunto(s)
Esquistosomiasis mansoni , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Biomphalaria , Brasil/epidemiología , Niño , Preescolar , Estudios Transversales , Vectores de Enfermedades , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Schistosoma mansoni , Esquistosomiasis mansoni/diagnóstico , Esquistosomiasis mansoni/epidemiología , Esquistosomiasis mansoni/transmisión , Adulto Joven
20.
PLoS One ; 15(9): e0232306, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32986707

RESUMEN

Tsetse eradication continues to be a top priority for African governments including that of Senegal, which embarked on a project to eliminate Glossina palpalis gambiensis from the Niayes area, following an area-wide integrated pest management approach with an SIT component. A successful SIT programme requires competitive sterile males of high biological quality. This may be hampered by handling processes including irradiation and the release mechanisms, necessitating continued improvement of these processes, to maintain the quality of flies. A new prototype of an automated chilled adult release system (Bruno Spreader Innovation, (BSI™)) for tsetse flies was tested for its accuracy (in counting) and release rate consistency. Also, its impact on the quality of the released sterile males was evaluated on performance indicators, including flight propensity, mating competitiveness, premating and mating duration, insemination rate of mated females and survival of male flies. The BSITM release system accurately counted and homogenously released flies at the lowest motor speed set (0.6 rpm), at a consistent rate of 60±9.58 males/min. Also, the release process, chilling (6 ± 1°C) and passing of flies through the machine) had no significant negative impact on the male flight propensity, mating competitiveness, premating and mating durations and the insemination rates. Only the survival of flies was negatively affected whether under feeding or starvation. The positive results of this study show that the BSI™ release system is promising for use in future tsetse SIT programmes. However, the negative impact of the release process on survival of flies needs to be addressed in future studies and results of this study confirmed under operational field conditions in West Africa.


Asunto(s)
Frío/efectos adversos , Infertilidad Masculina/veterinaria , Control Biológico de Vectores/métodos , Tripanosomiasis Africana/prevención & control , Moscas Tse-Tse/fisiología , Animales , Vectores de Enfermedades , Femenino , Vuelo Animal/fisiología , Humanos , Infertilidad Masculina/etiología , Ganado/parasitología , Masculino , Control Biológico de Vectores/instrumentación , Senegal , Conducta Sexual Animal/fisiología , Trypanosoma/patogenicidad , Tripanosomiasis Africana/parasitología , Tripanosomiasis Africana/veterinaria , Moscas Tse-Tse/parasitología
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