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1.
Emerg Infect Dis ; 30(12)2024 Oct 07.
Article in English | MEDLINE | ID: mdl-39374598

ABSTRACT

A febrile man in Italy who had traveled to Cuba in July 2024 was diagnosed with Oropouche fever. Reverse transcription PCR detected prolonged shedding of Oropouche virus RNA in whole blood, serum, urine, and semen. Sixteen days after symptom onset, replication-competent virus was detected in semen, suggesting risk for sexual transmission.

2.
Parasitol Res ; 123(10): 343, 2024 Oct 09.
Article in English | MEDLINE | ID: mdl-39382727

ABSTRACT

The increasing spread of mosquito vectors has made mosquito-borne arboviral diseases a global threat to public health, leading to the urgent need for effective population control methods. Strategies based in the intracellular bacterium Wolbachia Hertig, 1936 are considered environmentally friendly, safe for humans, and potentially cost-effective for controlling arboviral diseases. To minimize undesirable side effects, it is relevant to assess whether Wolbachia is present in the area and understand the diversity associated with native infections before implementing these strategies. With this purpose, we investigated Wolbachia infection status, diversity, and prevalence in populations of Aedes albifasciatus (Macquart, 1838), Aedes fluviatilis (Lutz, 1904), and hybrids of the Culex pipiens (Linnaeus, 1758) complex from Argentina. Aedes albifasciatus and C. pipiens complex samples were collected in the province of Buenos Aires, and A. fluviatilis in the province of Misiones. Aedes albifasciatus was found to be uninfected, while infections with strains wFlu and wPip were detected in A. fluviatilis and hybrids of the C. pipiens complex, respectively. All strains were fixed or close to fixation and clustered within supergroup B. These finding provides valuable information on Wolbachia strains found in natural mosquito populations in Argentina that might be used in heterologous infections in the future or be considered when designing control strategies based on Wolbachia infection.


Subject(s)
Aedes , Wolbachia , Wolbachia/isolation & purification , Wolbachia/genetics , Animals , Argentina , Aedes/microbiology , Aedes/virology , Culex/microbiology , Mosquito Vectors/microbiology , Female
4.
Rev Panam Salud Publica ; 48: e98, 2024.
Article in Portuguese | MEDLINE | ID: mdl-39411028

ABSTRACT

Objective: To identify and synthesize evidence of the effectiveness and cost-effectiveness of the Wolbachia-Aedes methodology for reducing cases of arboviral infection. Methodology: Rapid systematic review. A search of five online portals and bibliographic databases was conducted in February 2022. Two reviewers conducted the selection stages, with any disagreements resolved by a third investigator. Data were extracted by one reviewer and subsequently checked by another. The inclusion criteria were studies describing the cost-effectiveness and effectiveness of the Wolbachia-Aedes methodology, based on field interventions, published in Portuguese, English, and Spanish, with no restrictions on date of publication. Results: Four studies were included: one cluster randomized trial, two quasi-experimental studies, and one pre-post study, published between 2019 and 2021 in four countries. The included studies reported effectiveness for some of the outcomes of interest, such as a reduction in the incidence of dengue, Zika, and chikungunya cases. Although no experimental studies addressing the cost-effectiveness of the Wolbachia-Aedes strategy were identified, some modeling studies have demonstrated potential cost-benefit of this methodology. Conclusion: Considering the results of the included studies, Wolbachia has the potential to be an economically effective strategy that leads to reductions in the incidence of dengue, Zika, and chikungunya. Nevertheless, this strategy cannot yet be recommended as a public policy; additional large-scale studies with high methodological quality are still needed to inform political decision-making.


Objetivo: Señalar y sintetizar la evidencia sobre efectividad y costo-efectividad de la metodología de control de Aedes con Wolbachia para reducir los casos de arbovirosis. Método: Revisión sistemática rápida, con una búsqueda realizada en febrero del 2022 en cinco portales de búsqueda y bases de datos bibliográficas en línea. Las fases de selección estuvieron a cargo de dos revisores y la resolución de conflictos se asignó a un tercero. Un revisor extrajo los datos y luego otro los verificó. Los criterios de inclusión fueron: estudios que describieran la efectividad y la relación costo-efectividad de la metodología de control de Aedes con Wolbachia, basados en intervenciones sobre el terreno, publicados en portugués, inglés o español, sin restricciones en cuanto a la fecha de publicación. Resultados: Se incluyeron cuatro estudios, un ensayo aleatorizado por conglomerados, dos estudios cuasiexperimentales y uno de tipo antes-después, publicados entre el 2019 y el 2021 en cuatro países. En los estudios se obtuvieron resultados de efectividad en algunos de los criterios de valoración evaluados, como la reducción de la incidencia de casos de dengue, enfermedad de Zika y chikunguña. Aunque no se han encontrado estudios experimentales que aborden la costo-efectividad de la estrategia de control de Aedes con Wolbachia, algunos estudios de modelización han demostrado el posible costo-beneficio de esta estrategia. Conclusión: Teniendo en cuenta los resultados presentados, se puede concluir que la estrategia de control con Wolbachia tiene potencial para ser económicamente efectiva y conducir a una reducción de la incidencia de casos de dengue, enfermedad de Zika y chikunguña. Sin embargo, a pesar de ello, no es posible recomendar la estrategia como política pública, puesto que se requieren todavía más estudios a gran escala y de gran calidad metodológica para apoyar la toma de decisiones en materia de políticas.

5.
Mol Genet Genomics ; 299(1): 92, 2024 Oct 05.
Article in English | MEDLINE | ID: mdl-39367967

ABSTRACT

Aedes aegypti is an important vector of arboviruses, including dengue, chikungunya and Zika. The application of synthetic insecticides is a frequently used strategy to control this insect. Malathion is an organophosphate insecticide that was widely used in Brazil in the 1980s and 1990s to control the adult form of A. aegypti. In situations where resistance to currently used insecticides is detected, the use of malathion may be resumed as a control measure. Many studies have confirmed resistance to malathion, however, comparative studies of differential gene expression of the entire transcriptome of resistant and susceptible insects are scarce. Therefore, understanding the molecular basis of resistance to this insecticide in this species is extremely important. In this paper, we present the first transcriptomic description of susceptible and resistant strains of A. aegypti challenged with malathion. Guided transcriptome assembly resulted in 39,904 transcripts, where 2133 differentially expressed transcripts were detected, and three were validated by RT-qPCR. Enrichment analysis for these identified transcripts resulted in 13 significant pathways (padj < 0.05), 8 associated with down-regulated and 5 with up-regulated transcripts in treated resistant insects. It was possible to divide the transcripts according to the mechanism of action into three main groups: (i) genes involved in detoxification metabolic pathways; (ii) genes of proteins located in the membrane/extracellular region; and (iii) genes related to DNA integration/function. These results are important in advancing knowledge of genes related to resistance mechanisms in this insect, enabling the development of effective technologies and strategies for managing insecticide resistance.


Subject(s)
Aedes , Insecticide Resistance , Insecticides , Malathion , Transcriptome , Malathion/pharmacology , Animals , Aedes/genetics , Aedes/drug effects , Insecticide Resistance/genetics , Insecticides/pharmacology , Transcriptome/drug effects , Transcriptome/genetics , Gene Expression Profiling/methods , Mosquito Vectors/genetics , Mosquito Vectors/drug effects , Insect Proteins/genetics , Insect Proteins/metabolism
6.
Article in English | MEDLINE | ID: mdl-39422570

ABSTRACT

Background: Arboviruses are becoming a global public health menace. The common diseases worldwide caused by arboviruses are dengue, chikungunya, and Zika. This study aims to determine the prevalence of these three arboviral infections in patients with acute febrile illness at a tertiary care hospital in Kashmir, North India. Materials and Methods: A total of 812 blood samples were collected and tested for anti-dengue, anti-chikungunya immunoglobulin M (IgM), and dengue nonstructural protein 1 antigen by enzyme linked immunosorbent assay. Molecular testing of these samples was also done to detect dengue, chikungunya, and Zika viruses by using the CDC Trioplex real-time PCR assay. Results: The prevalence of diseases found among the studied patients was dengue 105/812 (12.93%) followed by chikungunya 17/812 (2.09%), and 3 cases (0.37%) were positive for both dengue and chikungunya; however, no case of Zika was detected. Interestingly, we found that only individuals that had a history of travel to different destinations within the country were positive for these viruses. Most affected cases were males 105/812 (12.93%) compared with females 20/812 (2.46%). Dengue serotyping results indicate that Dengue virus-1 was the most commonly found serotype. The most common symptoms in patients positive for dengue and chikungunya were fever, intense fatigue, myalgia, arthralgia, retro-orbital pain, anorexia, conjunctivitis, and skin rash. Conclusion: This study showed that dengue, chikungunya, and Zika viruses are not prevalent in the indigenous population of Kashmir. However, screening for these agents is required in people who have recently traveled outside Kashmir and have symptoms of acute febrile illness.

7.
Pathogens ; 13(9)2024 Aug 29.
Article in English | MEDLINE | ID: mdl-39338928

ABSTRACT

Among the main arboviruses affecting public health in tropical regions are dengue, zika, and chikungunya, transmitted mainly by mosquitoes of the Aedes genus, especially Aedes aegypti. In recent years, outbreaks have posed major challenges to global health, highlighting the need for integrated and innovative strategies for their control and prevention. Prevention strategies include the elimination of vectors and avoiding mosquito bites; this can be achieved through the use of bioinsecticides and repellents based on plant phytochemicals, as they offer sustainable, ecological, and low-cost alternatives. Mexico has a variety of plants from which both extracts and essential oils have been obtained which have demonstrated significant efficacy in repelling and/or killing insect vectors. This review examines the current knowledge on plant species found in Mexico which are promising options concerning synthetic compounds in terms of their repellent and insecticidal properties against mosquitoes of the genus Aedes and that are friendly to the environment and health.

8.
Pharmaceutics ; 16(9)2024 Aug 23.
Article in English | MEDLINE | ID: mdl-39339151

ABSTRACT

Diseases transmitted by arthropod-borne viruses such as West Nile virus (WNV) and chikungunya virus (CHIKV) pose threat to global public health. Unfortunately, to date, there is no available approved drug for severe symptoms caused by both viruses. It has been reported that reverse transcriptase inhibitors can effectively inhibit RNA polymerase activity of RNA viruses. We screened the anti-WNV activity of the FDA-approved reverse transcriptase inhibitor library and found that 4 out of 27 compounds showed significant antiviral activity. Among the candidates, etravirine markedly inhibited WNV infection in both Huh 7 and SH-SY5Y cells. Further assays revealed that etravirine inhibited the infection of multiple arboviruses, including yellow fever virus (YFV), tick-borne encephalitis virus (TBEV), and CHIKV. A deeper study at the phase of action showed that the drug works primarily during the viral replication process. This was supported by the strong interaction potential between etravirine and the RNA-dependent RNA polymerase (RdRp) of WNV and alphaviruses, as evaluated using molecular docking. In vivo, etravirine significantly rescued mice from WNV infection-induced weight loss, severe neurological symptoms, and death, as well as reduced the viral load and inflammatory cytokines in target tissues. Etravirine showed antiviral effects in both arthrophlogosis and lethal mouse models of CHIKV infection. This study revealed that etravirine is an effective anti-WNV and CHIKV arbovirus agent both in vitro and in vivo due to the inhibition of viral replication, providing promising candidates for clinical application.

9.
Medicina (Kaunas) ; 60(9)2024 Sep 23.
Article in English | MEDLINE | ID: mdl-39336598

ABSTRACT

Background and Objectives: The steady spread of dengue virus (DENV) poses a profound public health threat worldwide. Reverse transcription real-time polymerase chain reaction (RT2-PCR) has been increasingly recognized as a reference method for the diagnosis of acute dengue infection. The goal of this study was to assess the diagnostic accuracy of five different RT2-PCR kits for the detection of DENV in a historically processed set of sera samples. Materials and Methods: In this retrospective study, 25 sera samples from routinely processed unique adult patients with a known DENV status (previously tested in both molecular and serological assays) were tested in parallel using four conventional (RealStar Dengue PCR Kit 3.0, Clonit'ngo Zika, Dengue & Chikungunya, BioPerfectus Zika Virus/Dengue Virus/Chikungunya Virus Real Time PCR Kit and Novaplex Tropical fever virus) and one sample-to-result (STANDARD M10 Arbovirus Panel) RT2-PCR assays. Additionally, an end-point dilution analysis was conducted in quintuplicate on six serial dilutions of an RNA preparation obtained from a culture-grown DENV serotype 1 strain for a total of 150 tests. Results: The overall accuracy of the evaluated tests ranged from 84% to 100%. In particular, the sensitivity of three conventional RT2-PCR assays (RealStar, Clonit'ngo and Novaplex) was 100% (95% CI: 79.6-100%), while it was lower (73.3%; 95% CI: 48.1-89.1%) for the BioPerfectus kit. The sample-to-result STANDARD M10 panel performed comparatively well, showing a sensitivity of 92.9% (95% CI: 68.5-98.7%). No false positive results were registered in any assay. The end-point dilution analysis suggested that the RealStar kit had the lowest limit of detection. Conclusions: Available RT2-PCR kits for the detection of DENV are highly specific and generally sensitive and, therefore, their implementation in diagnostic pathways is advisable.


Subject(s)
Dengue Virus , Dengue , Real-Time Polymerase Chain Reaction , Sensitivity and Specificity , Humans , Dengue Virus/isolation & purification , Dengue Virus/genetics , Retrospective Studies , Dengue/diagnosis , Real-Time Polymerase Chain Reaction/methods , Real-Time Polymerase Chain Reaction/standards , Adult
10.
BMC Infect Dis ; 24(1): 1056, 2024 Sep 27.
Article in English | MEDLINE | ID: mdl-39333905

ABSTRACT

BACKGROUND: Dengue is a vector-borne viral infection caused by the dengue virus transmitted to humans primarily by Aedes aegypti. The year 2024 has been a historic year for dengue in Brazil, with the highest number of probable cases ever registered. Herein, we analyze the temporal trend and spatio-temporal dynamics of dengue cases in Brazil during the first nine epidemiological weeks (EW) of 2024. METHODS: This is an ecological study, including all probable cases of dengue in Brazil during the period, carried out in two steps: time series analysis to assess the temporal trend and spatial analysis to identify high-risk clusters. RESULTS: 1,345,801 probable cases of dengue were reported. The regions with the highest increasing trend were the Northeast with an average epidemiologic week percent change (AEPC) of 52.4 (95% CI: 45.5-59.7; p < 0.001) and the South with 35.9 (95% CI: 27.7-44.5; p < 0.001). There was a statistically significant increasing trend in all states, except Acre (AEPC = -4.1; 95% CI: -16.3-10; p = 0.55), Amapá (AEPC = 1.3; 95% CI: -16.2-22.3; p = 0.9) and Espírito Santo (AEPC = 8.9; 95% CI: -15.7-40.6; p = 0.5). The retrospective space-time analysis showed a cluster within the Northeast, Central-West and Southeast regions, with a radius of 515.3 km, in which 1,267 municipalities and 525,324 of the cases were concentrated (RR = 6.3; p < 0.001). Regarding the spatial variation of the temporal trend, 21 risk areas were found, all of them located in Southeast or Central-West states. The area with the highest relative risk was Minas Gerais state, where 5,748 cases were concentrated (RR = 8.1; p < 0.001). Finally, a purely spatial analysis revealed 25 clusters, the one with the highest relative risk being composed of two municipalities in Acre (RR = 6.9; p < 0.001). CONCLUSIONS: We described a detailed temporal-spatial analysis of dengue cases in the first EWs of 2024 in Brazil, which were mainly concentrated in the Southeast and Central-West regions. Overall, it is recommended that governments adopt public policies to control the the vector population in high-risk areas, as well as to prevent the spread of dengue fever to other areas of Brazil.


Subject(s)
Aedes , Dengue , Epidemics , Spatio-Temporal Analysis , Brazil/epidemiology , Dengue/epidemiology , Dengue/transmission , Humans , Epidemics/statistics & numerical data , Aedes/virology , Animals , Decision Making , Mosquito Vectors/virology , Dengue Virus
11.
BMC Public Health ; 24(1): 2587, 2024 Sep 27.
Article in English | MEDLINE | ID: mdl-39334102

ABSTRACT

BACKGROUND: The effectiveness of dengue control interventions depends on an effective integrated surveillance system that involves analysis of multiple variables associated with the natural history and transmission dynamics of this arbovirus. Entomological indicators associated with other biotic and abiotic parameters can assertively characterize the spatiotemporal trends related to dengue transmission risk. However, the unpredictability of the non-linear nature of the data, as well as the uncertainty and subjectivity inherent in biological data are often neglected in conventional models. METHODS: As an alternative for analyzing dengue-related data, we devised a fuzzy-logic approach to test ensembles of these indicators across categories, which align with the concept of degrees of truth to characterize the success of dengue transmission by Aedes aegypti mosquitoes in an endemic city in Brazil. We used locally gathered entomological, demographic, environmental and epidemiological data as input sources using freely available data on digital platforms. The outcome variable, risk of transmission, was aggregated into three categories: low, medium, and high. Spatial data was georeferenced and the defuzzified values were interpolated to create a map, translating our findings to local public health managers and decision-makers to direct further vector control interventions. RESULTS: The classification of low, medium, and high transmission risk areas followed a seasonal trend expected for dengue occurrence in the region. The fuzzy approach captured the 2020 outbreak, when only 14.06% of the areas were classified as low risk. The classification of transmission risk based on the fuzzy system revealed effective in predicting an increase in dengue transmission, since more than 75% of high-risk areas had an increase in dengue incidence within the following 15 days. CONCLUSIONS: Our study demonstrated the ability of fuzzy logic to characterize the city's spatiotemporal heterogeneity in relation to areas at high risk of dengue transmission, suggesting it can be considered as part of an integrated surveillance system to support timely decision-making.


Subject(s)
Aedes , Dengue , Fuzzy Logic , Mosquito Vectors , Dengue/epidemiology , Dengue/transmission , Humans , Animals , Aedes/virology , Brazil/epidemiology , Risk Assessment , Cities/epidemiology , Endemic Diseases/statistics & numerical data , Disease Outbreaks
12.
Emerg Infect Dis ; 30(10): 2155-2159, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39255237

ABSTRACT

Phylogenetic analyses showed that the virus responsible for a May 2024 Oropouche fever outbreak in Cuba was closely related to viruses from Brazil in 2023. Pools of Ceratopogonidae spp. biting midges and Culex quinquefasciatus mosquitoes were positive for Oropouche viral RNA. No cases were severe. Virus extension to new areas may increase case numbers and severity.


Subject(s)
Disease Outbreaks , Phylogeny , Cuba/epidemiology , Humans , Animals , Culex/virology , Male , Adult , Female , Middle Aged , Orthobunyavirus/genetics , Orthobunyavirus/classification , Bunyaviridae Infections/epidemiology , Bunyaviridae Infections/virology , Adolescent , Child , Young Adult , Aged , Ceratopogonidae/virology , RNA, Viral , Child, Preschool
13.
Emerg Infect Dis ; 30(10): 2208-2211, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39320216

ABSTRACT

We document a case of Rickettsia parkeri rickettsiosis in a patient in Connecticut, USA, who became ill after a bite from a Gulf Coast tick (Amblyomma maculatum). We used PCR to amplify R. parkeri DNA from the detached tick. The patient showed a 4-fold rise in IgG reactive with R. parkeri antigens.


Subject(s)
Amblyomma , Rickettsia Infections , Rickettsia , Rickettsia/genetics , Rickettsia/isolation & purification , Rickettsia/classification , Animals , Humans , Rickettsia Infections/microbiology , Rickettsia Infections/transmission , Rickettsia Infections/diagnosis , Amblyomma/microbiology , Connecticut , Tick Bites , Male , Female , Antibodies, Bacterial/blood
14.
Acta Trop ; 260: 107410, 2024 Sep 28.
Article in English | MEDLINE | ID: mdl-39349234

ABSTRACT

Dengue fever is a mosquito-transmitted disease of great public health importance. Dengue lacks adequate vaccine protection and insecticide-based methods of mosquito control are proving increasingly ineffective. Here we review the emerging use of mosquitoes transinfected with the obligate intracellular bacterium Wolbachia pipientis for vector control. Wolbachia often induces cytoplasmic incompatibility in its mosquito hosts, resulting in infertile progeny between an infected male and an uninfected female. Wolbachia infection also suppresses the replication of pathogens in the mosquito, a process known as "pathogen blocking". Two strategies have emerged. The first one releases Wolbachia carriers (both male and female) to replace the wild mosquito population, a process driven by cytoplasmic incompatibility and that becomes irreversible once a threshold is reached. This suppresses disease transmission mainly by pathogen blocking and frequently requires a single intervention. The second strategy floods the field population with an exclusively male population of Wolbachia-carrying mosquitoes to generate infertile hybrid progeny. In this case, transmission suppression depends largely on decreasing the population density of mosquitoes driven by infertility and requires continued mosquito release. The efficacy of both Wolbachia-based approaches has been conclusively demonstrated by randomized and non-randomized studies of deployments across the world. However, results conducted in one setting cannot be directly or easily extrapolated to other settings because dengue incidence is highly affected by the conditions into which the mosquitoes are released. Compared to traditional vector control methods, Wolbachia-based approaches are much more environmentally friendly and can be effective in the medium/long term. On the flip side, they are much more complex and cost-intensive operations, requiring a substantial investment, infrastructure, trained personnel, coordination between agencies, and community engagement. Finally, we discuss recent evidence suggesting that the release of Wolbachia-transinfected mosquitoes has a moderate potential risk of spreading potentially dangerous genes in the environment.

15.
Pharmaceutics ; 16(8)2024 Aug 21.
Article in English | MEDLINE | ID: mdl-39204441

ABSTRACT

Aedes mosquito-borne diseases remain a significant global health threat, necessitating effective control strategies. This study introduces monoterpenes-based nanohydrogels for potential use as repellents against Aedes aegypti, the primary dengue vector worldwide. We formulated hydrogels using cymene- and myrcene-based nanoemulsions with different polymers: chitosan, carboxymethylcellulose (CMC), and carbopol®. Our evaluations of rheological, texture, and bioadhesive properties identified CMC hydrogel as the most promising gelling agent for topical application, exhibiting sustained monoterpene release over 12 h with low skin permeation and high retention in the stratum corneum. Myrcene-loaded CMC hydrogel achieved a 57% feeding deterrence compared to 47% with cymene hydrogel in the mosquito membrane-feeding model. Molecular docking studies revealed interactions between myrcene and an essential amino acid (Ile116) in the Ae. aegypti odorant-binding protein 22 (AeOBP22), corroborating its higher repellent efficacy. These findings suggest that myrcene-loaded CMC hydrogels offer a promising, minimally invasive strategy for personal protection against Ae. aegypti and warrant further investigation to optimize monoterpene concentrations for vector control.

16.
Viruses ; 16(8)2024 Aug 19.
Article in English | MEDLINE | ID: mdl-39205296

ABSTRACT

Chikungunya virus (CHIKV) is a reemerging arbovirus causing disease on a global scale, and the potential for its epidemics remains high. CHIKV has caused millions of cases and heavy economic burdens around the world, while there are no available approved antiviral therapies to date. In this study, nifuroxazide, an FDA-approved antibiotic for acute diarrhea or colitis, was found to significantly inhibit a variety of arboviruses, although its antiviral activity varied among different target cell types. Nifuroxazide exhibited relatively high inhibitory efficiency in yellow fever virus (YFV) infection of the hepatoma cell line Huh7, tick-borne encephalitis virus (TBEV) and west nile virus (WNV) infection of the vascular endothelial cell line HUVEC, and CHIKV infection of both Huh7 cells and HUVECs, while it barely affected the viral invasion of neurons. Further systematic studies on the action stage of nifuroxazide showed that nifuroxazide mainly inhibited in the viral replication stage. In vivo, nifuroxazide significantly reduced the viral load in muscles and protected mice from CHIKV-induced footpad swelling, an inflammation injury within the arthrosis of infected mice. These results suggest that nifuroxazide has a potential clinical application as an antiviral drug, such as in the treatment of CHIKV infection.


Subject(s)
Antiviral Agents , Chikungunya Fever , Chikungunya virus , Hydroxybenzoates , Nitrofurans , Virus Replication , Animals , Mice , Humans , Chikungunya virus/drug effects , Chikungunya virus/physiology , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Virus Replication/drug effects , Nitrofurans/pharmacology , Nitrofurans/therapeutic use , Chikungunya Fever/drug therapy , Chikungunya Fever/virology , Hydroxybenzoates/pharmacology , Hydroxybenzoates/therapeutic use , Cell Line , Viral Load/drug effects , Human Umbilical Vein Endothelial Cells
17.
Viruses ; 16(8)2024 Aug 21.
Article in English | MEDLINE | ID: mdl-39205310

ABSTRACT

Wolbachia symbionts introduced into Aedes mosquitoes provide a highly effective dengue virus transmission control strategy, increasingly utilised in many countries in an attempt to reduce disease burden. Whilst highly effective against dengue and other positive-sense RNA viruses, it remains unclear how effective Wolbachia is against negative-sense RNA viruses. Therefore, the effect of Wolbachia on Bunyamwera virus (BUNV) infection in Aedes aegypti was investigated using wMel and wAlbB, two strains currently used in Wolbachia releases for dengue control, as well as wAu, a strain that typically persists at a high density and is an extremely efficient blocker of positive-sense viruses. Wolbachia was found to reduce BUNV infection in vitro but not in vivo. Instead, BUNV caused significant impacts on density of all three Wolbachia strains following infection of Ae. aegypti mosquitoes. The ability of Wolbachia to successfully persist within the mosquito and block virus transmission is partially dependent on its intracellular density. However, reduction in Wolbachia density was not observed in offspring of infected mothers. This could be due in part to a lack of transovarial transmission of BUNV observed. The results highlight the importance of understanding the complex interactions between multiple arboviruses, mosquitoes and Wolbachia in natural environments, the impact this can have on maintaining protection against diseases, and the necessity for monitoring Wolbachia prevalence at release sites.


Subject(s)
Aedes , Bunyamwera virus , Mosquito Vectors , Wolbachia , Wolbachia/physiology , Animals , Aedes/microbiology , Aedes/virology , Mosquito Vectors/microbiology , Mosquito Vectors/virology , Female , Symbiosis
18.
Emerg Infect Dis ; 30(9): 1763-1769, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39173658

ABSTRACT

Nematodes of the Onchocercidae family, such as Pelecitus spp., are filarial parasites of medical and veterinary importance. Although infections are widely distributed among avian species, only 2 cases of human Pelecitus ocular infection, both in South America, have been reported. We describe a 61-year-old man in northeast Thailand diagnosed with an ocular infection. Morphologic characteristics suggested the causative agent was a female Pelecitus nematode: coiled body, rounded anterior and posterior extremities, a distinct preesophageal cuticular ring, lateral alae, a postdeirid, and a protuberant vulva. Sequences of the 12S rDNA gene indicated 95%-96% identity and cox1 gene 92%-96% identity with published P. copsychi sequences. P-distance for cox1 sequences between the causative agent and P. copsychi was 6.71%. Phylogenetic trees of 12S rDNA and cox1 genes indicated the species differed from but is closely associated with P. copsychi. Healthcare providers should be aware of the threat of ocular infection from Pelecitus spp. nematodes.


Subject(s)
Phylogeny , Animals , Middle Aged , Thailand , Humans , Male , Female , RNA, Ribosomal/genetics
19.
Pharmacol Rep ; 76(5): 1147-1159, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39150661

ABSTRACT

BACKGROUND: Currently, there is no antiviral licensed to treat chikungunya fever, a disease caused by the infection with Alphavirus chikungunya (CHIKV). Treatment is based on analgesic and anti-inflammatory drugs to relieve symptoms. Our study aimed to evaluate the antiviral activity of sulfadoxine (SFX), an FDA-approved drug, and its derivatives complexed with silver(I) (AgSFX), salicylaldehyde Schiff base (SFX-SL), and with both Ag and SL (AgSFX-SL) against CHIKV. METHODS: The anti-CHIKV activity of SFX and its derivatives was investigated using BHK-21 cells infected with CHIKV-nanoluc, a marker virus-carrying nanoluciferase reporter. Dose-response and time of drug-addition assays were performed in order to assess the antiviral effects of the compounds, as well as in silico data and ATR-FTIR analysis for insights on their mechanisms of action. RESULTS: The SFX inhibited 34% of CHIKV replication, while AgSFX, SFX-SL, and AgSFX-SL enhanced anti-CHIKV activity to 84%, 89%, and 95%, respectively. AgSFX, SFX-SL, and AgSFX-SL significantly decreased viral entry and post-entry to host cells, and the latter also protected cells against infection. Additionally, molecular docking calculations and ATR-FTIR analysis demonstrated interactions of SFX-SL, AgSFX, and AgSFX-SL with CHIKV. CONCLUSIONS: Collectively, our findings suggest that the addition of metal ions and/or Schiff base to SFX improved its antiviral activity against CHIKV.


Subject(s)
Antiviral Agents , Chikungunya Fever , Chikungunya virus , Sulfadoxine , Chikungunya virus/drug effects , Antiviral Agents/pharmacology , Antiviral Agents/chemistry , Animals , Cell Line , Sulfadoxine/pharmacology , Chikungunya Fever/drug therapy , Chikungunya Fever/virology , Cricetinae , Schiff Bases/pharmacology , Silver/pharmacology , Silver/chemistry , Virus Replication/drug effects , Molecular Docking Simulation , Dose-Response Relationship, Drug , Humans , Aldehydes
20.
Emerg Infect Dis ; 30(10): 2196-2198, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39213265

ABSTRACT

We assessed the spatiotemporal dynamics of Oropouche fever in Brazil during 2015-2024. We found the number of cases substantially increased during that period, particularly in the Amazon region. Our findings underscore the need for improved surveillance and public health measures in response to the disease's potential spread beyond endemic areas.


Subject(s)
Spatio-Temporal Analysis , Brazil/epidemiology , Humans , History, 21st Century , Bunyaviridae Infections/epidemiology , Male , Female , Adult , Orthobunyavirus , Adolescent
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