RESUMEN
Seven years after the declaration of the first epidemic of Ebola virus disease in Guinea, the country faced a new outbreak-between 14 February and 19 June 2021-near the epicentre of the previous epidemic1,2. Here we use next-generation sequencing to generate complete or near-complete genomes of Zaire ebolavirus from samples obtained from 12 different patients. These genomes form a well-supported phylogenetic cluster with genomes from the previous outbreak, which indicates that the new outbreak was not the result of a new spillover event from an animal reservoir. The 2021 lineage shows considerably lower divergence than would be expected during sustained human-to-human transmission, which suggests a persistent infection with reduced replication or a period of latency. The resurgence of Zaire ebolavirus from humans five years after the end of the previous outbreak of Ebola virus disease reinforces the need for long-term medical and social care for patients who survive the disease, to reduce the risk of re-emergence and to prevent further stigmatization.
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Brotes de Enfermedades , Ebolavirus/genética , Ebolavirus/aislamiento & purificación , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/virología , Modelos Biológicos , Animales , República Democrática del Congo/epidemiología , Brotes de Enfermedades/estadística & datos numéricos , Ebolavirus/clasificación , Femenino , Guinea/epidemiología , Fiebre Hemorrágica Ebola/transmisión , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Infección Persistente/virología , Filogenia , Sobrevivientes , Factores de Tiempo , Zoonosis Virales/transmisión , Zoonosis Virales/virologíaRESUMEN
Locusta migratoria is a serious agricultural pest in China. Beauveria bassiana is one of the most important pathogens of grasshoppers and locusts. The effects of ultraviolet light were evaluated on the B. bassiana strain BbZJ1. The results showed that 253.7 and 360 nm wavelength UV (Ultra Violet) did not affect the germination of B. bassiana after its recovery from UV treatments. Nevertheless, the virulence of B. bassiana BbZJ1 after its recovery from radiation of UV (253.7 nm) increased. The mortality rates were 85.00% for the BbZJ1 control, was 96.67% for BbZJ1 recovered from radiation of UV (253.7 nm) for 60 min. After treatment with 253.7 nm UV radiation for 60 min, the expression levels of stress-resistant genes BbAlg9 and Bbadh2 in BbZJ1 strain were 2.68 and 2.29 times higher than those in the control group, respectively. Meanwhile, the B. bassiana prepared in 5% groundnut oil showed highest tolerance levels to the ultraviolet radiation. The 5% groundnut oil was the most suitable potential UV-protectant for B. bassiana in terms of cost and availability.
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Beauveria , Rayos Ultravioleta , Virulencia , Agricultura , China , Control Biológico de Vectores/métodosRESUMEN
The stability of symbiotic flora is an important indicator of the health of an organism. Symbiotic bacteria have been proven to be closely involved in the immune process of organisms. The pathogenicity of Beauveria bassiana was studied in relation to symbiotic bacteria on the surface and inside of the migratory locust (Locusta migratoria). The results showed that the surface disinfection of test locusts contributed to the pathogenicity of B. bassiana to locusts. Most of the surface bacteria of L. migratoria caused some inhibition of B. bassiana growth, and LM5-4 (Raoultella ornithinolytica), LM5-2 (Enterobacter aerogenes), and LM5-13 (Citrobacter freundii) showed the highest inhibitory effect on the growth of B. bassiana. The inoculation of locusts with additional surface symbiotic bacteria reduced the virulence of B. bassiana to L. migratoria. Infection by different strains of B. bassiana caused similar changes in the symbiotic flora of migratory locusts. The inoculation of locusts with additional intestinal symbiotic bacteria (Enterobacter sp.) reduced the virulence of B. bassiana to L. migratoria. These findings illustrate the effect of bacterial communities on fungal infections in L. migratoria when seen from the perspective of ecology in a microenvironment. The active antifungal substances of such bacteria and their mechanisms of action need further study.
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Beauveria , Locusta migratoria , Micosis , Animales , Locusta migratoria/fisiología , Antifúngicos , BacteriasRESUMEN
Malaria incidence is generally lower in cities than rural areas. However, reported urban malaria incidence may not accurately reflect the level of ongoing transmission, which has potentially large implications for prevention efforts. To guide mosquito net distribution, we assessed the extent of malaria transmission in Conakry, Guinea, in 2018. We found evidence of active malaria transmission.
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Anopheles , Malaria Falciparum , Malaria , Animales , Ciudades , Guinea/epidemiología , Malaria/epidemiología , Malaria Falciparum/epidemiología , Plasmodium falciparumRESUMEN
Based on MS and NMR data and bioassay-guided tracing, three insecticidal alkaloids I, II and III from Cynanchum mongolicum were identified to be antofine N-oxide, antofine and tylophorine. Alkaloid I was more toxic than alkaloids II and III, but they were less active against Spodoptera litura than total alkaloids. The contact toxicity from these alkaloids against the aphid Lipaphis erysimi was significant, as the 24 h-LC50 values of alkaloids I, II, III and total alkaloids were 292.48, 367.21, 487.791 and 163.52 mg/L, respectively. The development disruption of S. litura larvae was tested, the pupation and emergence rates of S. litura decreased and the acute mortality of S. litura increased significantly by day 3 after being injected in their body cavity with 10-40 mg/L of total alkaloid. The ecdysone titer of treated S. litura larvae and prepupae declined with increasing alkaloid concentration. The alkaloids of Cynanchum mongolicum are potential insect growth inhibitors.
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Alcaloides/química , Cynanchum/química , Insecticidas/farmacología , Alcaloides/farmacología , Animales , Inhibidores de Crecimiento/química , Inhibidores de Crecimiento/farmacología , Insecticidas/química , Larva/efectos de los fármacos , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/farmacología , Spodoptera/efectos de los fármacos , Spodoptera/crecimiento & desarrolloRESUMEN
INTRODUCTION: An electrocardiogram (ECG), combined with a well-conducted clinical examination, is more effective than the clinical examination alone in detecting underlying cardiac pathologies in athletes. The aim of this study was to evaluate the use of ECGs by physicians who are members of the Guinean Association of Sports Physicians, during the non-contraindication visit for competitive sports between the ages of 12 and 35. METHODOLOGY: We conducted a web-survey from July 15 to August 15, 2023. A survey form was created on "Google Docs" and pre-tested. It was then broadcast on all the communication networks used by these doctors. The data were secured using "Google Drive" software. Analyses were performed using SPSS version 20 software. RESULTS: Of the 51 included, 74.51% said they had received at least one training session on ECG interpretation for athletes. All of them either requested or performed an ECG at least once in a while, as part of the check-up for non-contraindication to competitive sport. The ECG was systematic, according to 72.55% of doctors. Three quarters referred to a sports cardiologist in the event of an abnormal ECG, 66.67% to a cardiology resident and 58.82% to a cardiologist. In the absence of an ECG, the presence of functional signs on exertion, the notion of a family history of cardiovascular disease and the presence of at least two cardiovascular risk factors were the main reasons for seeking an opinion. CONCLUSION: A resting ECG is carried out almost systematically by doctors who are members of the Guinean Association of Sports Doctors, as part of the check-up for non-contraindication to practising sport.
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Electrocardiografía , Medicina Deportiva , Deportes , Humanos , Adulto , Adolescente , Adulto Joven , Masculino , Femenino , Niño , Pautas de la Práctica en Medicina/estadística & datos numéricos , Encuestas y CuestionariosRESUMEN
Despite the numerous articles published on the clinical characteristics and outcomes of COVID-19 with regard to high-income countries, little is known about patients in low- and middle-income countries (LMIC) in this context. The objective of this observational, prospective, hospital-based multicentric study was to describe clinical features and outcomes of laboratory-confirmed COVID-19 patients hospitalized in each of the participating centers in Bangladesh, Guinea, Ivory Coast, Lebanon, Madagascar, and Mali during the first year of the pandemic (March 5, 2020 to May 4, 2021). The study outcome was the clinical severity of COVID-19, defined as hospitalization in intensive care unit or death. Multivariate logistic regression models were performed to identify independent variables associated with disease severity. Overall, 1,096 patients were included. The median age was 49.0 years, ranging from 38.0 in Mali to 63.0 years in Guinea. The overall clinical severity of COVID-19 was 12.3%, ranging from 6.4% in Mali to 18.8% in Guinea. In both groups of patients <60 and ≥60 years old, cardiovascular diseases (adjusted odds ratio [aOR]: 1.99; 95% CI: 1.13-3.50, P = 0.02; aOR: 2.47; 95% CI: 1.33-4.57, P = 0.004) were independently associated with clinical severity, whereas in patients <60 years, diabetes (aOR: 2.13; 95% CI: 1.11-4.10, P = 0.02) was also associated with clinical severity. Our findings suggest that COVID-19-related severity and death in LMICs are mainly driven by older age. However, the presence of chronic diseases can also increase the risk of severity especially in younger patients.
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COVID-19 , Humanos , Persona de Mediana Edad , Países en Desarrollo , Estudios Prospectivos , SARS-CoV-2 , Factores de Riesgo , Hospitalización , Estudios RetrospectivosRESUMEN
Epilepsy is a major public health problem in developing countries where eighty percent (80%) of people with epilepsy (PWE) live. Stigma has psychological consequences as well as serious repercussions on patients' quality of life. This study assesses the perception of health professionals in Africa regarding the stigmatization of PWE. METHODOLOGY: This is a multicenter descriptive, cross-sectional study, from 1st August 2020 to 1st September 2021. Medical practitioners from African countries involved in the management of epilepsy and who agreed to fill out forms were included in the study. Sampling was nonrandom and based on respondent choice. The data were analyzed using the EPI INFO 7 software. RESULTS: A total of two hundred and twenty-nine (229) health workers from twenty-six (26) African countries participated in this survey. 24.89% of the respondents were specialists and 46.72% were neurologists. Ninety-one percent (91%) of practitioners felt that PWE were stigmatised. The main forms of stigma were isolation (68.56%), celibacy (60.70%), unemployment (53.28%), divorce (44.54%) and exclusion (37.99%)%). Community, school and family were recognized as the main places of stigmatization. The fight against this stigma was carried out mainly in hospitals and in isolation in 58.4% and 55.8% of cases, respectively. Only 0.4% of practitioners opted for mass awareness. CONCLUSION: PWE are victims of various forms of stigmatization, particularly in community settings. Measures aimed at raising awareness of the public are essential to reduce this stigma and improve patients' quality of life.
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Epilepsia , Calidad de Vida , Humanos , Calidad de Vida/psicología , Estudios Transversales , Estigma Social , Epilepsia/psicología , Encuestas y Cuestionarios , África , Atención a la SaludRESUMEN
BACKGROUND: In a country where radiotherapy (RT) is not available, advocacy based on the relevance of surgery + adjuvant RT in locoregional control and survival is needed. AIM: To evaluate the impact of surgery with RT on local control and survival compared to surgery alone in breast cancer (BC). METHODS AND RESULTS: Between 2007 and 2016, 210 patients with BC were retrospectively reviewed, of which 90 patients underwent surgery with RT (group 1) and 120 patients' surgery (group 2). There were several treatment combinations, including surgery combined with neoadjuvant chemotherapy [ACT], RT, and ACT. The results showed 88 (41.9%) cases of relapse, including 31 (34.4%) (group 1) and 57 (47.5%) (group 2) (p = .046). Recurrence occurred after a mean time of 1.5 years in group 1 versus 0.66 years in group 2 (p = .006). The 5-year overall and BC-specific survivals were 49.5% and 62.5%, respectively. The 5-year survival was 60.0% (group 1) and 40.0% (group 2) (p < .05). In a multivariate analysis by Cox model, we found that the risk of death was 1.90 81 (95% CI [1.17 09-3.0701]) higher in group 2 (p = .009022), 1.69 85 (95% CI 1.00087-23.86157) in obese patients and decreased by 0.21 (95% CI [0.129-0.368]) in patients who did not relapse (p < .001). CONCLUSION: In this study with several combination therapies, we cannot confirm that RT improves mainly locally advanced BC prognosis regardless of systemic treatment. However, we found that the risk of death correlated with the absence of RT, overweight, and risk of recurrence. Consideration of combinations of locoregional and systemic therapies, clinicopathological and biological data could improve the relevance of these results with a large sample size.
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Neoplasias de la Mama , Neoplasias de la Mama/patología , Estudios de Cohortes , Femenino , Guinea , Humanos , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/prevención & control , Pronóstico , Estudios RetrospectivosRESUMEN
Data regarding the prevalence and consequences of self-medication during the COVID-19 pandemic in Africa are very limited. The study aimed to explore the frequency and risk factors of self-medication against COVID-19 by health personnel in this study. This cross-sectional study took place in June 2021, in Conakry, in the all three national hospitals and the six community medical centers, and five primary health centers. A multivariate logistic regression model was performed to identify factors associated with self-medication. A total of 975 health workers with a median age of 31 (IQR: 27-40) years, with 504 (51.7%) women were included. The majority were clinicians: physicians (33.1%) or nurses (33.1%). Of all, 46.2% reported having had at least one COVID-19 symptom during the 12 months preceding the survey. The proportion of self-medication was 15.3% among national hospital staff, 12.20% in municipality medical centers and 22.6% in primary health centers (p=0.06). More than two-thirds (68.7%) who selfmedicated did not have a test for SARSCoV- 2 infection. They took antibiotics including azithromycin, amoxicillin, ampicillin (42.2%), acetaminophen (37.4%), vitamin C (27.9%), hydroxychloroquine (23.8%) and medicinal plants (13.6%). The median duration of self-medication was 4 days. Fatigue or asthenia, sore throat, loss of smell and sore throat of a close person were independently associated with selfmedication. Health care workers largely practiced self-medication during the Covid pandemic and without diagnostic testing. The results suggest the need for training and sensitization of medical personnel to avoid the consequences of the molecules used, including hepatotoxicity and antibiotic resistance.
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The regional climate as it is now and in the future will put pressure on investments in sub-Saharan Africa in water resource management, fisheries, and other crop and livestock production systems. Changes in oceanic characteristics across the Atlantic Ocean will result in remarkable vulnerability of coastal ecology, littorals, and mangroves in the middle of the twenty-first century and beyond. In line with the countries' objectives of creating a green economy that allows reduced greenhouse gas emissions, improved resource efficiency, and prevention of biodiversity loss, we identify the most pressing needs for adaptation and the best adaptation choices that are also clean and affordable. According to empirical data from the field and customized model simulation designs, the cost of these adaptation measures will likely decrease and benefit sustainable green growth in agriculture, water resource management, and coastal ecosystems, as hydroclimatic hazards such as pluviometric and thermal extremes become more common in West Africa. Most of these adaptation options are local and need to be scaled up and operationalized for sustainable development. Governmental sovereign wealth funds, investments from the private sector, and funding from global climate funds can be used to operationalize these adaptation measures. Effective legislation, knowledge transfer, and pertinent collaborations are necessary for their success.
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Ecosistema , Gases de Efecto Invernadero , Recursos Hídricos , Cambio Climático , Agricultura , Conservación de los Recursos NaturalesRESUMEN
BACKGROUND: The Expanded Program on Immunisation has made it possible to prevent more than 3 million deaths in children under 5 years. The objectives of this study were to estimate the vaccination coverage of children from 0 to 59 months and identify factors associated with incomplete vaccination coverage. METHODS: A cross-sectional study was carried out in a dispensary in Conakry, Guinea between January and February 2020. Sociodemographic and vaccination information was collected from mothers of 380 randomly select children aged 0 to 59 months. Information on immunisation coverage was gathered from records vaccination cards and maternal reports. Logistic regression was used to identify factors independently associated with incomplete immunisation coverage. RESULTS: Most (66.5%) children aged < 12 months were up-to-date with their vaccinations. Factors associated with incomplete vaccination in this age group included: unavailability of vaccination cards (adjusted odds ratio [aOR] 7.58; 95% confidence interval [CI]: 2.56-22.44) and lack of prenatal consultation attendance (aOR 2.93; 95% CI: 1.15-7.48). In contrast only 19.8% (95% CI: 13.9-26.7) of children aged 12-59 months were fully immunised. Factors associated with incomplete vaccination coverage in children aged 12-59 months included high birth order (aOR 10.23; 95% CI: 2.06-19.43), and lack of prenatal consultation attendance (aOR 5.34; 95% CI: 1.48-19.23). CONCLUSION: Child immunisation coverage is low in Guinea. These results highlight the need to develop strategies based on an integrated approach to overcome obstacles to childhood immunisation in Guinea.
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BACKGROUND: Exclusive breastfeeding is critical for infant survival and development. However, the rate of exclusive breastfeeding in the first 6 months of life is low in sub-Saharan Africa. With the current trend in breastfeeding rates in many countries including in Guinea, the World Health Assembly target of at least 50% of children aged less than 6 months being exclusively breastfeed by 2025 is likely to be compromised and lives a numerous infant that are be at risk. The objective of this study was to identify the individual and contextual determinants of the practice of Exclusive Breastfeeding (EBF) in Guinea. METHOD: We conducted a secondary analysis of data from the 2018 Guinea Demographic and Health Survey (DHS). The study population consisted of women who gave birth between the ages of 15 and 49. Our sample consisted of women who had their last birth six (06) months prior to collection. The enumeration areas were our second level. A multilevel logistic regression was performed using Stata version 15.1 software. Three statistical models were implemented: The final model was obtained using the bottom-up step-by-step method. The intra-class correlation coefficient was calculated. RESULTS: On the 851 women included in our study, 33% reported having exclusively breastfed during the first 6 months of life of their children. After a multivariate analysis, the variables associated with exclusive breastfeeding are: children aged 2-3 months (OR = 0.53 CI95% = [0.36-0.79]) and children aged 4-5 months (OR = 0.23 IC95% = [0.14-0.36]), women in the Faranah area (OR = 2.69 IC95% = [1.21-5.94]) and those in Mamou (OR = 2.27 IC95% = [1.00-5.94]), women who gave birth in a health facility (OR = 1.94 IC95% = [1.34-2.80]) and women living in polygamous households (OR = 0.68 IC95% = [0.48-0.98]). CONCLUSION: The practice of exclusive breastfeeding remains low in Guinea. For the achievement of Sustainable Development Goals, particularly the improvement of exclusive breastfeeding practices, the individual and contextual determinants identified in this study should be taken into consideration in policies and programmes.
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BACKGROUND: The protocol study will focus on the seroprevalence of IgG antibodies to SARS-CoV-2 achieved by vaccination and/or natural protection as well as the history, symptoms, and risk factors for SARS-CoV-2 in four primary health-care workers (PHCWs) and their household contacts in metropolitan France. METHODS: Here, we propose a protocol for a nationwide survey to determine the seroprevalence of IgG antibodies to SARS-CoV-2 achieved by vaccination and/or natural protection in four PHCW populations (general practitioners, pediatricians, pharmacists and assistants, and dentists and assistants) and their household contacts. Participants will be included from June to July 2021 (Phase 1) among PHCW populations located throughout metropolitan France. They will be asked to provide a range of demographic and behavioral information since the first SARS-CoV-2 wave and a self-sampled dried blood spot. Phase 1 will involve also a questionnaire and serological study of PHCWs' household contacts. Seroprevalence will be estimated using two ELISAs designed to detect specific IgG antibodies to SARS-CoV-2 in humoral fluid, and these results will be confirmed using a virus neutralization test. This study will be repeated from November to December 2021 (Phase 2) to evaluate the evolution of immune status achieved by vaccination and/or natural protection of PHCWs and to describe the history of exposure to SARS-CoV-2.
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The ebola epidemic that raged in West Africa between 2013 and 2016 was the largest since the discovery of the virus in 1976. During this epidemic, more than 11,000 cases were notified with a lethality of over 67%. Several means of transmission have been described. The great difficulty noted during the epidemic was the estimation of the number of asymptomatic and pauci symptomatic cases, however there is evidence that this population has been in contact with the virus for some time. Thus, they could be a source for the spread of the epidemic. In this paper, we report in Guinea-Conakry three stories of probable pauci-symptomatic form of ebola disease that would have been the cause of massive infection in a population sorely tried by the epidemic between 2014 and 2015 in Guinea.
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Ebolavirus/aislamiento & purificación , Fiebre Hemorrágica Ebola/diagnóstico , Vigilancia de la Población , Adolescente , Adulto , Anciano , Femenino , Guinea/epidemiología , Fiebre Hemorrágica Ebola/epidemiología , Humanos , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: The prevalence of Ebola virus infection among people who have been in contact with patients with Ebola virus disease remains unclear, but is essential to understand the dynamics of transmission. This study aimed to identify risk factors for seropositivity and to estimate the prevalence of Ebola virus infection in unvaccinated contact persons. METHODS: In this retrospective, cross-sectional observational study, we recruited individuals between May 12, 2016, and Sept 8, 2017, who had been in physical contact with a patient with Ebola virus disease, from four medical centres in Guinea (Conakry, Macenta, N'zérékoré, and Forécariah). Contact persons had to be 7 years or older and not diagnosed with Ebola virus disease. Participants were selected through the Postebogui survivors' cohort. We collected self-reported information on exposure and occurrence of symptoms after exposure using a questionnaire, and tested antibody response against glycoprotein, nucleoprotein, and 40-kDa viral protein of Zaire Ebola virus by taking a blood sample. The prevalence of Ebola virus infection was estimated with a latent class model. FINDINGS: 1721 contact persons were interviewed and given blood tests, 331 of whom reported a history of vaccination so were excluded, resulting in a study population of 1390. Symptoms were reported by 216 (16%) contact persons. The median age of participants was 26 years (range 7-88) and 682 (49%) were male. Seropositivity was identified in 18 (8·33%, 95% CI 5·01-12·80) of 216 paucisymptomatic contact persons and 39 (3·32%, 5·01-12·80) of 1174 (2-4) asymptomatic individuals (p=0·0021). Seropositivity increased with participation in burial rituals (adjusted odds ratio [aOR] 2·30, 95% CI 1·21-4·17; p=0·0079) and exposure to blood or vomit (aOR 2·15, 1·23-3·91; p=0·0090). Frequency of Ebola virus infection varied from 3·06% (95% CI 1·84-5·05) in asymptomatic contact persons who did not participate in burial rituals to 5·98% (2·81-8·18) in those who did, and from 7·17% (3·94-9·09) in paucisymptomatic contact persons who did not participate in burial rituals to 17·16% (12·42-22·31) among those who did. INTERPRETATION: This study provides a new assessment of the prevalence of Ebola virus infection among contact persons according to exposure, provides evidence for the occurrence of paucisymptomatic cases, and reinforces the importance of closely monitoring at-risk contact persons. FUNDING: Institut National de la Santé et de la Recherche Médicale, Reacting, the French Ebola Task Force, Institut de Recherche pour le Développement, and Montpellier University Of Excellence-University of Montpellier.
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Anticuerpos Antivirales/sangre , Enfermedades Asintomáticas/epidemiología , Ebolavirus/inmunología , Fiebre Hemorrágica Ebola/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Estudios Transversales , Transmisión de Enfermedad Infecciosa , Exposición a Riesgos Ambientales , Femenino , Guinea/epidemiología , Fiebre Hemorrágica Ebola/patología , Fiebre Hemorrágica Ebola/transmisión , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Estudios Seroepidemiológicos , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Insects such as locusts and grasshoppers can reduce the effectiveness of pathogens and parasites by adopting different defense strategies. We investigated the behavioral thermopreference of Locusta migratoria manilensis (Meyen) (Orthoptera: Acrididae) induced by the fungus Beauveria bassiana, and the impact this behavior had on the fungal mycosis under laboratory conditions. By basking in higher temperature locations, infected nymphs elevated their thoracic temperature to 30-32.6 °C, which is higher than the optimum temperature (25°C) for B. bassiana conidial germination and hyphal development. A minimum thermoregulation period of 3 h/day increased survival of infected locusts by 43.34%. The therapeutic effect decreased when thermoregulation was delayed after initial infection. The fungus grew and overcame the locusts as soon as the thermoregulation was interrupted, indicating that thermoregulation helped the insects to cope with infection but did not completely rid them of the fungus. A significant enhancement in the number of haemocytes was observed in infected thermoregulating locusts, reaching levels that were even higher than those observed in the controls. In contrast, haemocyte concentration was severely reduced in infected insects that did not thermoregulate. In infected non-thermoregulating locusts, the reduction in haemocyte number was accompanied by an increase in fungal blastospore concentration that was obvious in the haemolymph by day four. In contrast, no circulating blastospores were found in the haemolymph of infected thermoregulating locusts three days post-inoculation. We also examined the phagocytic activity of infected insects in vivo by using fluorescein isothiocyanate (FITC)-labelled silica beads. The proportion of beads that was engulfed by haemocytes in infected, thermoregulating insects was similar to that in the controls throughout the experiment, whereas the rate of phagocytosis in infected, non-thermoregulating insects progressively decreased after infection. These findings demonstrated that behavioural thermoregulation can adversely affect B. bassiana mycosis in infected L. migratoria manilensis, thereby limiting the development of lethal entomopathogenic fungi in locusts. This is apparently accomplished through an increase in the levels of haemocytes, leading to greater phagocytic activity under certain environmental conditions.
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Beauveria/fisiología , Conducta Animal/fisiología , Regulación de la Temperatura Corporal/inmunología , Locusta migratoria/fisiología , Micosis/inmunología , Agricultura/métodos , Animales , Beauveria/patogenicidad , Hemocitos/inmunología , Hemolinfa/citología , Hemolinfa/inmunología , Interacciones Microbiota-Huesped/inmunología , Hifa/fisiología , Locusta migratoria/microbiología , Micosis/microbiología , Micosis/veterinaria , Ninfa/microbiología , Ninfa/fisiología , Control Biológico de Vectores/métodos , Fagocitos/inmunologíaRESUMEN
Aphids are important agricultural pests because of their feeding and, for many species, their ability to transmit plant pathogenic viruses. Orius sauteri (Poppius) (Hemiptera: Anthocoridae) is an important predator in northern China of many aphid species, including Aphis craccivora (Koch) (Hemiptera: Aphididae). We measured the functional response and intraspecific competition of O. sauteri under different densities of A. craccivora at several constant temperatures. Predation of O. sauteri on A. craccivora conformed to Holling's type II functional response at all temperatures tested. The predation capability of O. sauteri showed a significant correlation with temperature. The predation capacity of O. sauteri was highest at 25°C, at which temperature we found the highest instantaneous attack rate (a = 0.8711), the theoretical maximum number of aphids captured (181.36), and the shortest handling time (Th = 0.0055). Predation by O. sauteri increased progressively with temperature from 15 to 25°C, but then decreased at 30°C. Intraspecific competition of O. sauteri increased positively with predator density under all temperatures examined. Our results indicate O. sauteri has significant potential for use as a biocontrol agent, under a wide range of temperatures. The inverse density-dependent predation and intraspecific competition of O. sauteri suggests that to obtain the greatest degree of pest suppression, releases of O. sauteri should begin early in the cropping season and numbers released should take prey density into consideration.
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Hemípteros , Conducta Predatoria , Animales , Áfidos , Conducta Competitiva , TemperaturaRESUMEN
BACKGROUND: Paranosema locustae Canning, 1953 (Microsporidia) provides effective control of grasshoppers. Horizontal transmission of P. locustae is known to occur, and evidence for the mechanism of this transmission via predatory natural enemies has been found. We conducted a 3-year laboratory and field study to assess the potential impact of feces from both grasshoppers Locusta migratoria L. and their natural enemies on the persistence of P. locustae. RESULTS: We found that P. locustae persisted among grasshopper populations in treated areas and in adjacent untreated areas for up to 2 years, and the density of grasshoppers decreased in both areas. We showed that healthy grasshoppers could be infected by eating food contaminated by feces from their natural enemies. Grasshopper predators retained a large number of spores acquired from eating grasshoppers infected with P. locustae. Spores in the feces of the main natural enemy, the beetle Pterostichus gebleri Dejean 1828, in the treated area showed clear viability. CONCLUSION: These results demonstrate that predatory natural enemies are important vectors for this microsporidian disease, and suggest that sustainable transmission and continuing population suppression might be achieved by horizontal transmission via natural enemies, which should be maximized to increase the effectiveness of P. locustae. © 2018 Society of Chemical Industry.
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Cadena Alimentaria , Saltamontes/microbiología , Microsporidios/fisiología , Control Biológico de Vectores , Esporas Fúngicas/fisiología , Animales , China , Heces/microbiología , Locusta migratoria/microbiologíaRESUMEN
The objective of our study was to report the management and follow-up of a particular case of ballistic trauma and to do the literature review. OBSERVATION: A 35-year-old patient, a trader who was the victim of a firearm accident under not very clear circumstances. He was admitted to the emergency department after 3 hours. Clinically, the patient had significant bleeding in the arm and was in a state of clouding of consciousness. We could notice on the right arm, a posterior large transfixing wound of 1 cm and a 6 cm one on the antero-internal side. The limb was cold with a small and thready pulse. Sensitivity was decreased in the radial nerve area. The radiograph showed bone comminution from the middle 1/3 to the superior 1/3 of the humeral diaphysis. The treatment was orthopedic (after debridement) by scapula-brachio-ante-brachiopalmar plaster splint with thoracic strap. The wound healed in 46 days and the patient resumed his activities after 11 months and 2 weeks. CONCLUSION: The authors presented the value of using the scapulo-brachio-palmar plaster splints with thoracic strap in some severe upper limb trauma in the absence of the external fixator.