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1.
Sci Rep ; 14(1): 12620, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824239

RESUMO

Ivermectin (IVM) has been proposed as a new tool for malaria control as it is toxic on vectors feeding on treated humans or cattle. Nevertheless, IVM may have a direct mosquitocidal effect when applied on bed nets or sprayed walls. The potential for IVM application as a new insecticide for long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) was tested in this proof-of-concept study in a laboratory and semi-field environment. Laboratory-reared, insecticide-susceptible Kisumu Anopheles gambiae were exposed to IVM on impregnated netting materials and sprayed plastered- and mud walls using cone bioassays. The results showed a direct mosquitocidal effect of IVM on this mosquito strain as all mosquitoes died by 24 h after exposure to IVM. The effect was slower on the IVM-sprayed walls compared to the treated nettings. Further work to evaluate possibility of IVM as a new insecticide formulation in LLINs and IRS will be required.


Assuntos
Anopheles , Mosquiteiros Tratados com Inseticida , Inseticidas , Ivermectina , Controle de Mosquitos , Animais , Anopheles/efeitos dos fármacos , Ivermectina/farmacologia , Inseticidas/farmacologia , Controle de Mosquitos/métodos , Malária/prevenção & controle , Malária/transmissão , Mosquitos Vetores/efeitos dos fármacos
2.
bioRxiv ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38854158

RESUMO

Invasive insects threaten ecosystem stability, public health, and food security. Documenting newly invasive species and understanding how they reach into new territories, establish populations, and interact with other species remain vitally important. Here, we report on the invasion of the South American leafhopper, Curtara insularis into Africa, where it has established populations in Ghana, encroaching inland at least 350 km off the coast. Importantly, 80% of the specimens collected were intercepted between 160 and 190 m above ground. Further, the fraction of this species among all insects collected was also higher at altitude, demonstrating its propensity to engage in high-altitude windborne dispersal. Its aerial densities at altitude translate into millions of migrants/km over a year, representing massive propagule pressure. Given the predominant south-westerly winds, these sightings suggest an introduction of C. insularis into at least one of the Gulf of Guinea ports. To assess the contribution of windborne dispersal to its spread in a new territory, we examine records of C. insularis range-expansion in the USA. Reported first in 2004 from central Florida, it reached north Florida (Panhandle) by 2008-2011 and subsequently spread across the southeastern and south-central US. Its expansion fits a "diffusion-like" process with 200-300 km long "annual displacement steps"-a pattern consistent with autonomous dispersal rather than vehicular transport. Most "steps" are consistent with common wind trajectories from the nearest documented population, assuming 2-8 hours of wind-assisted flight at altitude. Curtara insularis has been intercepted at US ports and on trucks. Thus, it uses multiple dispersal modalities, yet its rapid overland spread is better explained by its massive propagule pressure linked with its high-altitude windborne dispersal. We propose that high-altitude windborne dispersal is common yet under-appreciated in invasive insect species.

3.
Case Rep Dermatol ; 15(1): 225-230, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38054030

RESUMO

Introduction: Bart's syndrome is an uncommon inherited congenital disorder associating congenital cutaneous aplasia of the extremities and inherited epidermolysis bullosa. Bilateral and symmetrical involvement of the limbs is exceptionally described on black skin. In most cases, the diagnosis is clinical; however, the management remains very difficult and the extended forms are a real therapeutic challenge. We report 2 cases of Bart's syndrome observed in a sub-Saharan African country (Senegal, Dakar). Case Presentation: It was about 2 premature female and male newborns. On physical examination, the girl presented with a total absence of skin on the limbs, associated with cutaneous detachment of the trunk representing a detached and detachable skin surface of 46%; the boy underwent a total absence of skin of more than 50% of the skin surface. The diagnosis of Bart's syndrome was set based on the typical clinical aspect. The blood count and CRP were normal for the girl whereas it revealed some disorders for the boy. The 2 newborns were urgently admitted to an incubator, and the intensive care was started with hyperhydration, anti-staphylococcal prophylaxis, and daily dermatological care with antiseptic baths and fatty dressings. Conclusion: Bart's syndrome is an uncommon genodermatosis characterized by a clinical triad associating congenital cutaneous aplasia of the extremities, inherited epidermolysis bullosa suspected in the presence of bubbles, and areas of cutaneous fragility and nail deformity. All types of which can be associated with this syndrome. The easy clinical diagnosis but the difficult management encumber the vital prognosis of our cases.

4.
Artigo em Inglês | MEDLINE | ID: mdl-37947557

RESUMO

OBJECTIVES: The goal of this study was to evaluate the application of the short form of the International Physical Activity Questionnaire Survey (IPAQ-SF) in the rural Senegalese Fulani pastoralist population by combining quantitative and qualitative methods. DESIGN AND PARTICIPANTS: For the quantitative method, 101 men completed the IPAQ-SF questionnaire measuring moderate, vigorous, and walking physical activity. Self-rated health, BMI, and sociodemographic variables were also collected. With regard to the qualitative methods, a total of 22 participants were recruited and interviewed. Four themes were addressed, including (i) physical activity (PA) and its definition, description, related experiences, and representations of social actors; (ii) PA and health; (iii) PA and sport; and (iv) the body and Fulani world of life (i.e., Pulaagu/Ndimaagu). RESULTS: Sahelian herders have a high level of self-reported PA and a low amount of daily sitting time. The measure of PA as proposed by the IPAQ-SF is not adapted to the Senegalese Ferlo pastoralists, mainly because this scale gives too much importance to leisure-time PA, perceived as unproductive energy expenditure, which is factually and symbolically antinomic to the Fulani lifeworld. Thus, neither intense nor moderate PA is related to self-rated health. However, sedentary lifestyles are linked to self-rated health and, therefore, to mortality and morbidity in Fulani pastoralists. Finally, walking, which is the dominant PA during transhumance and herd surveillance, is related to BMI. It therefore represents a protective factor against the occurrence of overweight and associated chronic non-communicable diseases. CONCLUSION: The mixed method approach developed in this study has shown that the IPAQ-SF is not a valid measure of PA in the population of Fulani male herders from the Ferlo region, given that unproductive energy expenditure is incompatible with the Fulani way of life, which condemns excess and immoderation.


Assuntos
Exercício Físico , Atividade Motora , Humanos , Masculino , Inquéritos e Questionários , Autorrelato , Caminhada
5.
medRxiv ; 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37398491

RESUMO

The spread of SARS-CoV-2 cannot be well monitored and understood in areas without capacity for effective disease surveillance. Countries with a young population will have disproportionately large numbers of asymptomatic or pauci-symptomatic infections, further hindering detection of infection in the population. Sero-surveillance on a country-wide scale by trained medical professionals may be limited in scope in resource limited setting such as Mali. Novel ways of broadly sampling the human population in a non-invasive method would allow for large-scale surveillance at a reduced cost. Here we evaluate the collection of naturally bloodfed mosquitoes to test for human anti-SARS-CoV-2 antibodies in the laboratory and at five field locations in Mali. Immunoglobulin-G antibodies were found to be readily detectable within the mosquito bloodmeals by a bead-based immunoassay at least through 10 hours post-feeding with high sensitivity (0.900 ± 0.059) and specificity (0.924 ± 0.080), respectively, indicating that most blood-fed mosquitoes collected indoors during early morning hours (and thus, have likely fed the previous night) are viable samples for analysis. We find that reactivity to four SARS-CoV-2 antigens rose during the pandemic from pre-pandemic levels. Consistent with other sero-surveillance studies in Mali, crude seropositivity of blood sampled via mosquitoes was 6.3% in October/November 2020 over all sites, and increased to 25.1% overall, with the town closest to Bamako reaching 46.7% in February of 2021. Mosquito bloodmeals a viable target for conventional immunoassays, and therefore country-wide sero-surveillance of human diseases (both vector-borne and non-vector-borne) is attainable in areas where human-biting mosquitoes are common, and is an informative, cost-effective, non-invasive sampling option.

6.
J Med Entomol ; 60(4): 698-707, 2023 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-37094808

RESUMO

Knowledge of insect dispersal is relevant to the control of agricultural pests, vector-borne transmission of human and veterinary pathogens, and insect biodiversity. Previous studies in a malaria endemic area of the Sahel region in West Africa revealed high-altitude, long-distance migration of insects and various mosquito species. The objective of the current study was to assess whether similar behavior is exhibited by mosquitoes and other insects around the Lake Victoria basin region of Kenya in East Africa. Insects were sampled monthly from dusk to dawn over 1 year using sticky nets suspended on a tethered helium-filled balloon. A total of 17,883 insects were caught on nets tethered at 90, 120, and 160 m above ground level; 818 insects were caught in control nets. Small insects (<0.5 cm, n = 15,250) were predominant regardless of height compared with large insects (>0.5 cm, n = 2,334) and mosquitoes (n = 299). Seven orders were identified; dipteran was the most common. Barcoding molecular assays of 184 mosquitoes identified 7 genera, with Culex being the most common (65.8%) and Anopheles being the least common (5.4%). The survival rate of mosquitoes, experimentally exposed to high-altitude overnight, was significantly lower than controls maintained in the laboratory (19% vs. 85%). There were no significant differences in mosquito survival and oviposition rate according to capture height. These data suggest that windborne dispersal activity of mosquito vectors of malaria and other diseases occurs on a broad scale in sub-Saharan Africa.


Assuntos
Anopheles , Malária , Feminino , Humanos , Animais , Vento , Altitude , África Oriental , Mosquitos Vetores , Controle de Mosquitos
7.
Front Epidemiol ; 3: 1243691, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38455906

RESUMO

Background: The spread of SARS-CoV-2 cannot be well monitored and understood in areas without capacity for effective disease surveillance. Countries with a young population will have disproportionately large numbers of asymptomatic or pauci-symptomatic infections, further hindering detection of infection. Sero-surveillance on a country-wide scale by trained medical professionals may be limited in a resource-limited setting such as Mali. Novel ways of broadly sampling the human population in a non-invasive method would allow for large-scale surveillance at a reduced cost. Approach: Here we evaluate the collection of naturally blood-fed mosquitoes to test for human anti-SARS-CoV-2 antibodies in the laboratory and at five field locations in Mali. Results: Immunoglobulin-G antibodies to multiple SARS-CoV-2 antigens were readily detected in mosquito bloodmeals by bead-based immunoassay through at least 10 h after feeding [mean sensitivity of 0.92 (95% CI 0.78-1) and mean specificity of 0.98 (95% CI 0.88-1)], indicating that most blood-fed mosquitoes collected indoors during early morning hours (and likely to have fed the previous night) are viable samples for analysis. We found that reactivity to four SARS-CoV-2 antigens rose during the pandemic from pre-pandemic levels. The crude seropositivity of blood sampled via mosquitoes was 6.3% in October and November 2020 across all sites, and increased to 25.1% overall by February 2021, with the most urban site reaching 46.7%, consistent with independent venous blood-based sero-surveillance estimates. Conclusions: We have demonstrated that using mosquito bloodmeals, country-wide sero-surveillance of human diseases (both vector-borne and non-vector-borne) is possible in areas where human-biting mosquitoes are common, offering an informative, cost-effective, and non-invasive sampling option.

8.
Nat Ecol Evol ; 6(11): 1687-1699, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36216903

RESUMO

Data suggest that the malaria vector mosquito Anopheles coluzzii persists during the dry season in the Sahel through a dormancy mechanism known as aestivation; however, the contribution of aestivation compared with alternative strategies such as migration is unknown. Here we marked larval Anopheles mosquitoes in two Sahelian villages in Mali using deuterium (2H) to assess the contribution of aestivation to persistence of mosquitoes through the seven-month dry season. After an initial enrichment period, 33% of An. coluzzii mosquitoes were strongly marked. Seven months following enrichment, multiple analysis methods supported the ongoing presence of marked mosquitoes, compatible with the prediction that the fraction of marked mosquitoes should remain stable throughout the dry season if local aestivation is occurring. The results suggest that aestivation is a major persistence mechanism of An. coluzzii in the Sahel, contributing at least 20% of the adults at the onset of rains. This persistence strategy could influence mosquito control and malaria elimination campaigns.


Assuntos
Anopheles , Malária , Animais , Estivação , Estações do Ano , Mosquitos Vetores
9.
Pathogens ; 11(9)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36145453

RESUMO

Widespread of insecticide resistance amongst the species of the Anopheles gambiae complex continues to threaten vector control in Senegal. In this study, we investigated the presence and evolution of the Ace-1 and Gste2 resistance genes in natural populations of Anopheles gambiae s.l., the main malaria vector in Senegal. Using historical samples collected from ten sentinel health districts, this study focused on three different years (2013, 2017, and 2018) marking the periods of shift between the main public health insecticides families (pyrethroids, carbamates, organophosphates) used in IRS to track back the evolutionary history of the resistance mutations on the Ace-1 and Gste2 loci. The results revealed the presence of four members of the Anopheles gambiae complex, with the predominance of An. arabiensis followed by An. gambiae, An. coluzzii, and An. gambiae-coluzzii hybrids. The Ace-1 mutation was only detected in An. gambiae and An. gambiae-coluzzii hybrids at low frequencies varying between 0.006 and 0.02, while the Gste2 mutation was found in all the species with a frequency ranging between 0.02 and 0.25. The Ace-1 and Gste2 genes were highly diversified with twenty-two and thirty-one different haplotypes, respectively. The neutrality tests on each gene indicated a negative Tajima's D, suggesting the abundance of rare alleles. The presence and spread of the Ace-1 and Gste2 resistance mutations represent a serious threat to of the effectiveness and the sustainability of IRS-based interventions using carbamates or organophosphates to manage the widespread pyrethroids resistance in Senegal. These data are of the highest importance to support the NMCP for evidence-based vector control interventions selection and targeting.

10.
Afr J Reprod Health ; 26(5): 50-56, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-37585096

RESUMO

The objectives of this study were to compare perinatal outcomes in twin pregnancies where the first twin was in the breech presentation. To do so, we performed a 10-year retrospective cohort study in a single university center. All patients with a twin pregnancy with the first twin in breech presentation, a gestational age greater than or equal to 34 weeks' gestation, and a birth weight <= 1500 g were included. The main outcome measures were 5-minute Apgar score <7 and perinatal mortality. We included 353 pairs of twins which complied with the inclusion criteria. One hundred and fifty (150) patients delivered vaginally while 203 pairs of twins were delivered by caesarean section. Patients who delivered abdominally were similar to those who delivered vaginally with regard to age, parity, and gestational age. Six twins A delivered vaginally and 2 delivered by caesarean section had an Apgar score < 7 (p = 0.76) whereas 12 twins B delivered vaginally and 2 delivered abdominally had an Apgar score <7 (p = 0.001). Perinatal mortality did not differ significantly between twins delivered abdominally and those delivered vaginally. There was no evidence that vaginal delivery was risky with regards to depressed Apgar scores for Twin A and neonatal mortality for breech first twins that weighed at least 1500 g. However, Twin B delivered vaginally were more likely to present with a low 5-minute Apgar score. Along with the literature, the findings of this study do not currently allow to define a consensual obstetric attitude towards management of breech first twin deliveries. Until more prospective multicenter randomized controlled studies shed light on this problem, the skills, experience and judgment of the obstetrician will play a major role in the decision-making process.


Assuntos
Apresentação Pélvica , Recém-Nascido , Gravidez , Humanos , Feminino , Lactente , Apresentação Pélvica/epidemiologia , Cesárea , Gravidez de Gêmeos , Estudos de Coortes , Estudos Retrospectivos , Estudos Prospectivos , Senegal/epidemiologia , Parto Obstétrico , Resultado da Gravidez/epidemiologia
11.
Front Epidemiol ; 2: 1001782, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-38455321

RESUMO

Recent studies have reported Anopheles mosquitoes captured at high-altitude (40-290 m above ground) in the Sahel. Here, we describe this migration modality across genera and species of African Culicidae and examine its implications for disease transmission and control. As well as Anopheles, six other genera-Culex, Aedes, Mansonia, Mimomyia, Lutzia, and Eretmapodites comprised 90% of the 2,340 mosquitoes captured at altitude. Of the 50 molecularly confirmed species (N = 2,107), 33 species represented by multiple specimens were conservatively considered high-altitude windborne migrants, suggesting it is a common migration modality in mosquitoes (31-47% of the known species in Mali), and especially in Culex (45-59%). Overall species abundance varied between 2 and 710 specimens/species (in Ae. vittatus and Cx. perexiguus, respectively). At altitude, females outnumbered males 6:1, and 93% of the females have taken at least one blood meal on a vertebrate host prior to their departure. Most taxa were more common at higher sampling altitudes, indicating that total abundance and diversity are underestimated. High-altitude flight activity was concentrated between June and November coinciding with availability of surface waters and peak disease transmission by mosquitoes. These hallmarks of windborne mosquito migration bolster their role as carriers of mosquito-borne pathogens (MBPs). Screening 921 mosquitoes using pan-Plasmodium assays revealed that thoracic infection rate in these high-altitude migrants was 2.4%, providing a proof of concept that vertebrate pathogens are transported by windborne mosquitoes at altitude. Fourteen of the 33 windborne mosquito species had been reported as vectors to 25 MBPs in West Africa, which represent 32% of the MBPs known in that region and include those that inflict the heaviest burden on human and animal health, such as malaria, yellow fever, dengue, and Rift Valley fever. We highlight five arboviruses that are most likely affected by windborne mosquitoes in West Africa: Rift Valley fever, O'nyong'nyong, Ngari, Pangola, and Ndumu. We conclude that the study of windborne spread of diseases by migrating insects and the development of surveillance to map the sources, routes, and destinations of vectors and pathogens is key to understand, predict, and mitigate existing and new threats of public health.

12.
Genes (Basel) ; 12(12)2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34946897

RESUMO

The evolution and spread of insecticide resistance mechanisms amongst malaria vectors across the sub-Saharan Africa threaten the effectiveness and sustainability of current insecticide-based vector control interventions. However, a successful insecticide resistance management plan relies strongly on evidence of historical and contemporary mechanisms circulating. This study aims to retrospectively determine the evolution and spread of pyrethroid resistance mechanisms among natural Anopheles gambiae s.l. populations in Senegal. Samples were randomly drawn from an existing mosquito sample, collected in 2013, 2017, and 2018 from 10 sentinel sites monitored by the Senegalese National Malaria Control Programme (NMCP). Molecular species of An. gambiae s.l. and the resistance mutations at the Voltage-gated Sodium Channel 1014 (Vgsc-1014) locus were characterised using PCR-based assays. The genetic diversity of the Vgsc gene was further analyzed by sequencing. The overall species composition revealed the predominance of Anopheles arabiensis (73.08%) followed by An. gambiae s.s. (14.48%), Anopheles coluzzii (10.94%) and Anopheles gambiae-coluzii hybrids (1.48%). Both Vgsc-1014F and Vgsc-1014S mutations were found in all studied populations with a spatial variation of allele frequencies from 3% to 90%; and 7% to 41%, respectively. The two mutations have been detected since 2013 across all the selected health districts, with Vgsc-L1014S frequency increasing over the years while Vgsc-1014F decreasing. At species level, the Vgsc-1014F and Vgsc-1014S alleles were more frequent amongst An. gambiae s.s. (70%) and An. arabiensis (20%). The Vgsc gene was found to be highly diversified with eight different haplotypes shared between Vgsc-1014F and Vgsc-1014S. The observed co-occurrence of Vgsc-1014F and Vgsc-1014S mutations suggest that pyrethroid resistance is becoming a widespread phenomenon amongst malaria vector populations, and the NMCP needs to address this issue to sustain the gain made in controlling malaria.


Assuntos
Anopheles/genética , Proteínas de Insetos/genética , Resistência a Inseticidas/genética , Mosquitos Vetores/genética , Mutação , Piretrinas/farmacologia , Canais de Sódio Disparados por Voltagem/genética , Animais , Frequência do Gene , Inseticidas/farmacologia , Estudos Retrospectivos , Senegal , Canais de Sódio Disparados por Voltagem/metabolismo
13.
Pan Afr Med J ; 39: 51, 2021.
Artigo em Francês | MEDLINE | ID: mdl-34422174

RESUMO

The purpose of this study was to compare the unadjusted EPOPé M0 curve with the customized Gardosi curve in the diagnosis of small-for-gestational-age (SGA) fetuses in a sub-Saharan population. We compared the Gardosi et al. and EPOPé M0 classifications. Classification differences were analyzed according to patient characteristics and obstetric conditions. Data collected from FileMaker software were analyzed using SPSS 20.0 and R Studio software. The statistical tests were carried out according to applicability conditions. Alpha risk was set at 0.05. The Gardosi curve showed that the rate of SGA newborns was higher (31.4% versus 28.9%) and did not differ between overweight and normal-weight women. The rate of severe SGA in preterm infants was also higher (23.6 versus 19.7%). Diseases were more frequent in newborns classified as severe SGA by the customized growth curve. The customized curve is recommended for the sub-Saharan Africa population.


Assuntos
Desenvolvimento Fetal/fisiologia , Retardo do Crescimento Fetal/diagnóstico , Recém-Nascido Prematuro/crescimento & desenvolvimento , Adulto , África Subsaariana , Estudos de Coortes , Feminino , Retardo do Crescimento Fetal/classificação , Idade Gestacional , Humanos , Recém-Nascido , Masculino , Sobrepeso/epidemiologia , Gravidez , Valores de Referência , Estudos Retrospectivos , Índice de Gravidade de Doença , Adulto Jovem
14.
Methods Ecol Evol ; 12(6): 1008-1016, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34249305

RESUMO

Current mark-release-recapture methodologies are limited in their ability to address complex problems in vector biology, such as studying multiple groups overlapping in space and time. Additionally, limited mark retention, reduced post-marking survival and the large effort in marking, collection and recapture all complicate effective insect tracking.We have developed and evaluated a marking method using a fluorescent dye (SmartWater®) combined with synthetic DNA tags to informatively and efficiently mark adult mosquitoes using an airbrush pump and nebulizer. Using a handheld UV flashlight, the fluorescent marking enabled quick and simple initial detection of recaptures in a field-ready and non-destructive approach that when combined with an extraction-free PCR on individual mosquito legs provides potentially unlimited marking information.This marking, first tested in the laboratory with Anopheles gambiae s.l. mosquitoes, did not affect survival (median ages 24-28 days, p-adj > 0.25), oviposition (median eggs/female of 28.8, 32.5, 33.3 for water, green, red dyes, respectively, p-adj > 0.44) or Plasmodium competence (mean oocysts 5.56-10.6, p-adj > 0.95). DNA and fluorescence had 100% retention up to 3 weeks (longest time point tested) with high intensity, indicating marks would persist longer.We describe a novel, simple, no/low-impact and long-lasting marking method that allows separation of multiple insect subpopulations by combining unlimited length and sequence variation in the synthetic DNA tags. This method can be readily deployed in the field for marking multiple groups of mosquitoes or other insects.

15.
Ther Adv Infect Dis ; 8: 20499361211020879, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34123381

RESUMO

A 9-year-old girl presented a large inflammatory cup-shaped scalp lesion with alopecia surrounded by pustules, dander, and suppuration associated with an occipital inflammatory lymphadenopathy for 1 month. Wood's light exam was positive as well as KOH mount showing ectothrix type hair involvement. Hair and pus culture on Sabouraud dextrose agar (SDA) added with chloramphenicol and supplemented with cycloheximide isolated a dermatophyte species identified as Microsporum audouinii according to the colonies features. Species identification was confirmed by matrix-assisted laser desorption-ionization-time of flight mass spectrometry (MALDI-TOF MS) and the patient was treated for kerion celsi with terbinafine tablets 125 mg per day associated with a ketoconazole-based shampoo. The evolution was favorable, with hair regrowth after 2 months.

16.
J Med Entomol ; 58(1): 343-349, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-32667040

RESUMO

Recent results of high-altitude windborne mosquito migration raised questions about the viability of these mosquitoes despite ample evidence that many insect species, including other dipterans, have been known to migrate regularly over tens or hundreds of kilometers on high-altitude winds and retain their viability. To address these concerns, we subjected wild Anopheles gambiae s.l. Giles mosquitoes to a high-altitude survival assay, followed by oviposition (egg laying) and blood feeding assays. Despite carrying out the survival assay under exceptionally harsh conditions that probably provide the lowest survival potential following high altitude flight, a high proportion of the mosquitoes survived for 6- and even 11-h assay durations at 120- to 250-m altitudes. Minimal differences in egg laying success were noted between mosquitoes exposed to high altitude survival assay and those kept near the ground. Similarly, minimal differences were found in the female's ability to take an additional bloodmeal after oviposition between these groups. We conclude that similar to other high-altitude migrating insects, mosquitoes are able to withstand extended high-altitude flight and subsequently reproduce and transmit pathogens by blood feeding on new hosts.


Assuntos
Migração Animal , Anopheles/fisiologia , Comportamento Alimentar , Mosquitos Vetores/fisiologia , Oviposição , Sobrevida , Altitude , Animais , Feminino , Malária , Mali , Vento
17.
Sci Rep ; 10(1): 20523, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33239619

RESUMO

Long-distance migration of insects impacts food security, public health, and conservation-issues that are especially significant in Africa. Windborne migration is a key strategy enabling exploitation of ephemeral havens such as the Sahel, however, its knowledge remains sparse. In this first cross-season investigation (3 years) of the aerial fauna over Africa, we sampled insects flying 40-290 m above ground in Mali, using nets mounted on tethered helium-filled balloons. Nearly half a million insects were caught, representing at least 100 families from thirteen orders. Control nets confirmed that the insects were captured at altitude. Thirteen ecologically and phylogenetically diverse species were studied in detail. Migration of all species peaked during the wet season every year across localities, suggesting regular migrations. Species differed in flight altitude, seasonality, and associated weather conditions. All taxa exhibited frequent flights on southerly winds, accounting for the recolonization of the Sahel from southern source populations. "Return" southward movement occurred in most taxa. Estimates of the seasonal number of migrants per species crossing Mali at latitude 14°N were in the trillions, and the nightly distances traversed reached hundreds of kilometers. The magnitude and diversity of windborne insect migration highlight its importance and impacts on Sahelian and neighboring ecosystems.


Assuntos
Altitude , Migração Animal/fisiologia , Biodiversidade , Insetos/fisiologia , Animais , Voo Animal/fisiologia , Geografia , Mali , Filogenia , Estações do Ano , Especificidade da Espécie
18.
Pan Afr Med J ; 36: 379, 2020.
Artigo em Francês | MEDLINE | ID: mdl-33235656

RESUMO

Cysticercosis is a neglected tropical disease set as health priority by WHO. Most of the reported cases included isolated types of cysticercosis affecting the skin, the eyes or the brain . Disseminated types, however, are rare. We here report a case of disseminated cysticercosis affecting the brain, the eyes and the skin in a Senegalese female patient aged 66 years admitted with headaches and chronic seizures. Clinical examination showed cerebellar syndrome associated with generalized and painless nodular subcutaneous lesions. Diagnosis was confirmed based on histopathological examination of skin biopsy which showed cysticerci. Patient's outcome was good under albendazole therapy.


Assuntos
Encéfalo/parasitologia , Cisticercose/diagnóstico , Olho/parasitologia , Pele/parasitologia , Idoso , Albendazol/administração & dosagem , Encéfalo/patologia , Cisticercose/tratamento farmacológico , Cisticercose/patologia , Diagnóstico Diferencial , Olho/patologia , Infecções Oculares Parasitárias/diagnóstico , Infecções Oculares Parasitárias/tratamento farmacológico , Infecções Oculares Parasitárias/patologia , Feminino , Cefaleia/diagnóstico , Cefaleia/tratamento farmacológico , Cefaleia/parasitologia , Humanos , Neurocisticercose/diagnóstico , Neurocisticercose/tratamento farmacológico , Neurocisticercose/patologia , Fenobarbital/administração & dosagem , Prednisolona/administração & dosagem , Convulsões/diagnóstico , Convulsões/tratamento farmacológico , Convulsões/parasitologia , Senegal , Pele/patologia , Dermatopatias Parasitárias/diagnóstico , Dermatopatias Parasitárias/tratamento farmacológico
19.
Pan Afr Med J ; 35: 136, 2020.
Artigo em Francês | MEDLINE | ID: mdl-32655750

RESUMO

ABSTRACT: The purpose of this study was to assess the outcome of surgical management of osteoporotic vertebral fractures with percutaneous kyphoplasty using expandible SpineJack® implant. METHODS: We conducted an analytical retrospective single-center study over a period of 33-months (April 2015 - December 2017). It involved patients treated with kyphoplasty for an osteoporotic vertebral fracture. The kit consisted of a Vexim SpineJack® expandable titanium implant and acrylic cement. Patients with back pain increasing in intensity despite treatment for an osteoporotic vertebral fracture were included in the study as well as those who had undergone surgery and had given their informed consent. The vertebral fracture was diagnosed based on CT scan results and its recent state was confirmed by MRI. RESULTS: Between april 2015 and december 2017, thirty-seven patients with osteoporotic vertebral fractures were treated with kyphoplasty using expandable titanium vertebral implant. The average age of patients was 73.4 years, with a sex ratio of 0.6. Mean visual analog scale score was 7.3. Mean Oswestry score was 81.6. The patients mainly had fractures of the thoracolumbar hinge. Mean vertebral kyphotic angle was 18.45°. Kyphoplasty was used for the treatment of 44 vertebrae. Four patients had surgical complications. The average length of stay in hospital was 5.4 days. After a follow-up period of 6 months, 9 patients were still receiving analgesic therapy. After one year, no adjacent level fracture was found. CONCLUSION: Percutaneous kyphoplasty using expandible titanium implant is a safe and effective therapeutic mean for osteoporotic vertebral fractures. Given its almost immediate result, patients can rapidly get back to their active lives.


Assuntos
Cifoplastia/métodos , Fraturas por Osteoporose/cirurgia , Próteses e Implantes , Fraturas da Coluna Vertebral/cirurgia , Idoso , Idoso de 80 Anos ou mais , Analgésicos/administração & dosagem , Dor nas Costas/etiologia , Cimentos Ósseos , Feminino , Seguimentos , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Titânio , Resultado do Tratamento
20.
Malar J ; 19(1): 263, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32698842

RESUMO

BACKGROUND: In the West African Sahel, mosquito reproduction is halted during the 5-7 month-long dry season, due to the absence of surface waters required for larval development. However, recent studies have suggested that both Anopheles gambiae sensu stricto (s.s.) and Anopheles arabiensis repopulate this region via migration from distant locations where larval sites are perennial. Anopheles coluzzii engages in more regional migration, presumably within the Sahel, following shifting resources correlating with the ever-changing patterns of Sahelian rainfall. Understanding mosquito migration is key to controlling malaria-a disease that continues to claim more than 400,000 lives annually, especially those of African children. Using tethered flight data of wild mosquitoes, the distribution of flight parameters were evaluated as indicators of long-range migrants versus appetitive flyers, and the species specific seasonal differences and gonotrophic states compared between two flight activity modalities. Morphometrical differences were evaluated in the wings of mosquitoes exhibiting high flight activity (HFA) vs. low flight activity (LFA). METHODS: A novel tethered-flight assay was used to characterize flight in the three primary malaria vectors- An. arabiensis, An. coluzzii and An. gambiae s.s. The flights of tethered wild mosquitoes were audio-recorded from 21:00 h to 05:00 h in the following morning and three flight aptitude indices were examined: total flight duration, longest flight bout, and the number of flight bouts during the assay. RESULTS: The distributions of all flight indices were strongly skewed to the right, indicating that the population consisted of a majority of low-flight activity (LFA) mosquitoes and a minority of high-flight activity (HFA) mosquitoes. The median total flight was 586 s and the maximum value was 16,110 s (~ 4.5 h). In accordance with recent results, flight aptitude peaked in the wet season, and was higher in gravid females than in non-blood-fed females. Flight aptitude was also found to be higher in An. coluzzii compared to An. arabiensis, with intermediate values in An. gambiae s.s., but displaying no statistical difference. Evaluating differences in wing size and shape between LFA individuals and HFA ones, the wing size of HFA An. coluzzii was larger than that of LFAs during the wet season-its length was wider than predicted by allometry alone, indicating a change in wing shape. No statistically significant differences were found in the wing size/shape of An. gambiae s.s. or An. arabiensis. CONCLUSIONS: The partial agreement between the tethered flight results and recent results based on aerial sampling of these species suggest a degree of discrimination between appetitive flyers and long-distance migrants although identifying HFAs as long-distance migrants is not recommended without further investigation.


Assuntos
Migração Animal , Anopheles/fisiologia , Voo Animal , Malária/transmissão , Mosquitos Vetores/fisiologia , Animais , Variação Biológica Individual , Estações do Ano , Especificidade da Espécie
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