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Identificação molecular e perfil de resistência de V. Cholerae de ambientes aquáticos em zonas endémicas na província de Sofala após o ciclone IDAI

2026-07-20T12:18:19Z

Title: Identificação molecular e perfil de resistência de V. Cholerae de ambientes aquáticos em zonas endémicas na província de Sofala após o ciclone IDAI Authors: Nhassengo, Fernando Caetano Abstract: Vibrio cholerae é uma bactéria Gram-negativa responsavel por causar cólera em humanos, faz parte da flora natural do ambiente aquatico de regiões temperadas e tropicais do mundo. O serogrupo O1 é responsavel por provocar surtos epidémicos de cólera, doença transmitida principalmente pela ingestão de alimentos ou agua contaminada. Em Moçambique a cólera é endémica. Objectivos: Este estudo teve como objectivo, avaliar a presença de V. cholerae O1 no ambiente aquatico na província de Sofala e determinar o perfil de resistência antimicrobiana (RAM) numa area fortemente afectada por uma epidemia de cólera após o ciclone Idai. Metodologia: A presente pesquisa é um estudo observacional transversal prospectivo, onde um total de 77 amostras de agua colhidas de valas de drenagem, poços e rio dos distritos de Dondo, Nhamatanda e Cidade da Beira foram analisadas. Isolados suspeitos de V. cholerae foram identificados fenotipicamente e confirmados por testes bioquímicos Kliger Iron Agar (KIA), Simmons Citrate Agar, Ureia Agar base, Sulphate Indol Motility (SIM). Foram realizados testes de susceptibilidade antimicrobiana in vitro pelo método de difusão em disco (Kirby-Bauer) para a determinação do perfil de resistência antimicrobiana e a para confirmação da presença de genes de virulência e resistência antimicrobiana foi usado o PCR convencional e sequenciamento. Posteriormente foram realizadas analises filogenéticas dos isolados e comparados com isolados criopreservados provenientes de amostras clínicas do período anterior ao ciclone Idai. Resultados: De 66 isolados suspeitos, 26 foram confirmados como V. cholerae O1 oriundos das amostras da Beira. Destes, 21 (80.8%), 12 (46,2%) e 1 (3,8%) foram resistentes a Ciprofloxacina, Cefotaxime e Gentamicina, respectivamente. Destes, 17 foram seleccionados, sequenciados e re-confirmados como sendo V. cholerae O1 e usando o programa Bioinformatico ResFinder demonstraram potencial resistência à Estreptomicina, Florfenicol, Cloranfenicol, Sulfametoxazol e Trimetroprina. Conclusões: Nossos dados demonstraram a importância do ambiente aquatico para a saúde pública como reservatório de V. cholerae patogénico e sugerem que houve a introdução de estirpes filogeneticamente mais próximas a isolados da Índia antes do ciclone Idai. A monitoria contínua de estirpes ambientais de V. cholerae e do perfil de RAM de estirpes epidémicas é crucial para as estratégias de controle da cólera

A distribution model for Glossina brevipalpis and Glossina austeni in Southern Mozambique, Eswatini and South Africa for enhanced area-wide integrated pest management approaches

2024-08-29T11:26:58Z

Title: A distribution model for Glossina brevipalpis and Glossina austeni in Southern Mozambique, Eswatini and South Africa for enhanced area-wide integrated pest management approaches Authors: Beer, Chantel J. de; Dicko, Ahmadou H.; Ntshangase, Jerome; Moyaba, Percy; Taioe, Moeti O.; Mulandane, Fernando C.; Neves, Luis; Mdluli, Sihle; Guerrini, Laure; Bouyer, Jérémy; Vreysen, Marc J. B.; Venter, Gert J. Abstract: Glossina austeni and Glossina brevipalpis (Diptera: Glossinidae) are the sole cyclical vec- tors of African trypanosomes in South Africa, Eswatini and southern Mozambique. These populations represent the southernmost distribution of tsetse flies on the African continent. Accurate knowledge of infested areas is a prerequisite to develop and implement efficient and cost-effective control strategies, and distribution models may reduce large-scale, exten- sive entomological surveys that are time consuming and expensive. The objective was to develop a MaxEnt species distribution model and habitat suitability maps for the southern tsetse belt of South Africa, Eswatini and southern Mozambique.The present study used existing entomological survey data of G. austeni and G. brevipalpis to develop a MaxEnt species distribution model and habitat suitability maps. Distribution models and a checkerboard analysis indicated an overlapping presence of the two species and the most suitable habitat for both species were protected areas and the coastal strip in KwaZulu-Natal Province, South Africa and Maputo Province, Mozambique. The predicted presence extents, to a small degree, into communal farming areas adjacent to the protected areas and coastline, especially in the Matutuı́ne District of Mozambique. The quality of theMaxEnt model was assessed using an independent data set and indicated good perfor- mance with high predictive power (AUC > 0.80 for both species).The models indicated that cattle density, land surface temperature and protected areas, in relation with vegetation are the main factors contributing to the distribution of the two tsetse species in the area. Changes in the climate, agricultural practices and land-use have had a significant and rapid impact on tsetse abundance in the area. The model predicted low habi- tat suitability in the Gaza and Inhambane Provinces of Mozambique, i.e., the area north of the Matutuı́ne District. This might indicate that the southern tsetse population is isolated from the main tsetse belt in the north of Mozambique. The updated distribution models will be useful for planning tsetse and trypanosomosis interventions in the area.

Assessing the impact of rice cultivation and off-season period on dynamics of soil enzyme activities and bacterial communities in two agro-ecological regions of Mozambique

2024-08-29T09:52:35Z

Title: Assessing the impact of rice cultivation and off-season period on dynamics of soil enzyme activities and bacterial communities in two agro-ecological regions of Mozambique Authors: Ezeokoli, Obinna T.; Nuaila, Valter N. A.; Obieze, Chinedu C.; Muetanene, Belo A.; Fraga, Irene; Tesinde, Maria Natalia; Ndayiragije, Alexis; Coutinho, João; Melo, Ana M. P.; Adeleke, Rasheed A.; Barros, Ana I. Ribeiro; Fangueiro, David Abstract: Soil ecosystem perturbation due to agronomic practices can negatively impact soil pro- ductivity by altering the diversity and function of soil health determinants. Currently, the influence of rice cultivation and off-season periods on the dynamics of soil health determinants is unclear. Therefore, soil enzyme activities (EAs) and bacterial community compositions in rice-cultivated fields at postharvest (PH) and after a 5-month off-season period (5mR), and fallow-fields (5-years-fallow, 5YF; 10-years-fallow, 10YF and/or one-year-fallow, 1YF) were assessed in two agroecological regions of Mozambique. EAs were mostly higher in fallow fields than in PH, with significant (p < 0.05) differences detected for β-glucosidase and acid phosphatase activities. Only β-glucosidase activity was significantly (p < 0.05) different between PH and 5mR, suggesting that β-glucosidase is respon- sive in the short-term. Bacterial diversity was highest in rice-cultivated soil and correlated with NO 3 − , NH 4 + and electrical conductivity. Differentially abundant genera, such as Agromyces, Bacil- lus, Desulfuromonas, Gaiella, Lysobacter, Micromonospora, Norcadiodes, Rubrobacter, Solirubrobacter and Sphingomonas were mostly associated with fallow and 5mR fields, suggesting either negative effects of rice cultivation or the fallow period aided their recovery. Overall, rice cultivation and chemical parameters influenced certain EAs and shaped bacterial communities. Furthermore, the 5-month off-season period facilitates nutrient recovery and proliferation of plant-growth-promoting bacteria

Ticks and tick-borne pathogens infecting livestock and dogs in Tchicala-Tcholoanga, Huambo Province, Angola

2024-08-29T09:42:13Z

Title: Ticks and tick-borne pathogens infecting livestock and dogs in Tchicala-Tcholoanga, Huambo Province, Angola Authors: Sili, Gourgélia; Byaruhanga, Charles; Horak, Ivan; Steyn, Helena; Chaisi, Mamohale; Oosthuizen, Marinda C.; Neves, Luís Abstract: The diversity of ticks and tick-borne pathogens (TBPs) infesting domestic animals in Tchicala-Tcholoanga, Angola, in 2016 was investigated. Seventeen tick species were recorded, Amblyomma pomposum being the most abundant on cattle (40%), goats (38%) and sheep (35%); Rhipicephalus turanicus was the most abundant on dogs (46%). This study presents new records of Haemaphysalis paraleachi, R. compositus, R. kochi and R. sulcatus in Angola, the first georeferenced population of Ha. leachi in southern Africa and the second record of R. microplus in Angola. Using the reverse line blot (RLB) hybridisation assay, fifteen TBP species were detected in blood samples from cattle (n = 88), goats (n = 82), sheep (n = 85) and dogs (n = 85). F The most frequently detected species were Theileria velifera in cattle (78%), Theileria ovis in sheep (80%) and Babesia vogeli in dogs (35%). Species-specific quantitative PCR assays detected Babesia bigemina in 43% (35/80) of blood samples of cattle, while E. ruminantium was detected in 4% (3/70) of blood samples and in 7% of A. pomposum ticks. Anaplasma platys was detected from cattle (18%) and sheep (6%) during RLB analysis. These findings constitute pioneering research in Angola.