Chikungunya transmission was confirmed in Perico, Matanzas Province, Cuba. Initial research confirmed the presence of East/Central/South African genotype related to Brazil 2025 strains in serum samples and in Aedes aegypti mosquito pools from transmission areas. Our findings underscore the need for surveillance and signal potential spread to other regions.

Background and objectives:The coronavirus disease 2019 (COVID-19) pandemic highlighted the influence of behavioral and environmental factors on the risk of infection, as well as on disease progression and severity. Therefore, it is critical to improve public health knowledge regarding the factors influencing disease outcomes. This study describes the development and validation of the "Cuban population environmental and lifestyle factors Questionnaire" (CELF-Q), a tool designed to evaluate the impact of environmental and lifestyle factors on COVID-19 outcomes in the Cuban population. Study design and setting:Based on an existing lifestyle questionnaire developed for the Latin American population, a thorough process of modification, cross-cultural adaptation, and iterative desk review was conducted to generate the CELF-Q. Pre-test analysis was performed to assess face and content validity. To evaluate content validity, a panel of 15 experts was selected. Test-retest reliability was assessed in 60 participants, while internal consistency was evaluated by administering the questionnaire to 309 individuals with SARS-CoV-2 infection. Confirmatory factor analysis (CFA) was performed to assess the fit of the CELF-Q's factor structure. Results:The content validity of the questionnaire was deemed "acceptable" across several dimensions, based on the results of the content validity ratio (CVR), content validity index (CVI), and Aiken's validity (V). Only a few items were identified for revision using these quantitative measures. Additionally, the experts supplemented the evaluations with qualitative comments for the modification of the questions. The test-retest reliability analysis showed an overall mean kappa coefficient of 0.89 [standard deviation (SD): 0.21] and a mean overall correlation coefficient of 0.99 (0.02), indicating high to almost perfect agreement. An internal consistency analysis showed that the majority of the dimensions had acceptable Cronbach's alpha values. In particular, the self-care behavior, socioeconomic restrictions, and diet and nutritional habits dimensions achieved respectable Cronbach's alpha values (between 0.7 and 0.8). Conclusion:The generated CELF-Q is a comprehensive, valid, and reliable tool for obtaining information on environmental/lifestyle factors associated with SARS-CoV-2 infection, as well as the development and severity of COVID-19, in the Cuban population.

In 2025, chikungunya virus (CHIKV) re-emerged in Cuba after nine years without reported local transmission, with over 51 000 cases. We identified ten infected travellers returning to France from Cuba. Phylogenetic analysis showed that these viral genomes belong to the ECSA-2 genotype and cluster with recent Latin American sequences. These findings highlight the value of traveller-based genomic surveillance and underscore the risk of CHIKV expansion to other regions.

Oropouche virus (OROV) was reported in Cuba in May 2024 and rapidly spread throughout the country. Here, among 147 reverse-transcription polymerase chain reaction-positive cases identified from May to July 2024, we sequenced 39 whole genomes of OROV. Phylogenetic analysis revealed that all sequences formed a monophyletic cluster nested within the reassortant lineage, named OROVBR-2015-2025, which has been circulating extensively in Brazil since 2023. Additional phylogeographic analyses demonstrated that the Cuban subclade probably originated from a single viral introduction from the Brazilian state of Acre in early February 2024, followed by cryptic circulation until its identification in May. The introduction probably occurred in the central region of the country, from which the virus spread and established secondary transmission hubs in the western and eastern regions. These findings underscore the capacity of OROV to spread well beyond South America, which was considered its endemic area of circulation.

Zika virus (ZIKV) nonstructural protein 1 (NS1) represents a valuable diagnostic target due to its early secretion during infection and reduced cross-reactivity with other flaviviruses. Optimization of NS1 expression conditions is essential for obtaining large-scale protein production. The use of bacterial expression systems as Escherichia coli offers a cost-effective platform. We developed two molecular cloning strategies to express full-length ZIKV NS1 (1053 bp) from Cuban strain 9661/2016 using pQE30/XL1-Blue and pET50b(+)/BL21(DE3) expression systems. The ns1 gene cloned via pGEM-T intermediate vector, and subcloned into expression vectors by using directional restriction-based strategy. The effects of culture medium and IPTG concentration on bacterial growth and protein accumulation was evaluated in order to optimizing the NS1 expression conditions. Both expression systems successfully produced recombinant ZIKV NS1. However, the BL21(DE3)/pET50b(+) system yielded soluble NS1, whereas the XL1-Blue/pQE30 system predominantly produced insoluble protein. Culture medium exerted a greater effect on protein expression than IPTG concentration, with LB medium and 0.1 mM IPTG providing the most favorable conditions for recombinant NS1 production. Notably, XL1-Blue demonstrated competency for protein expression. The pET50b(+)-ns1/BL21(DE3) system offers decisive advantages through soluble expression, eliminating refolding requirements for downstream purification process. This work establishes optimized protocols for ZIKV NS1 expression applicable to obtaining a recombinant protein for developing an ELISA system and broadly transferable to other flavivirus antigens.

Early identification of individuals at risk of complications is important to improve dengue case-management and promote appropriate use of limited resources in high burden settings. In this prospective observational cohort, 7428 febrile outpatients were enrolled across 8 countries in Asia and Latin America and followed daily; 2230 individuals with confirmed dengue were included in the analysis, among whom 304 (14%) progressed to moderate/severe dengue and 38 (2%) to severe dengue during follow-up. We demonstrate evolving relationships between common clinical features, WHO clinical warning signs, and simple haematological parameters, with progression. Key predictors of moderate/severe dengue include low lymphocyte percentage, low total white blood cell count, low platelet count, and persistent vomiting and significant abdominal pain/tenderness. Multivariable models incorporating these variables predict the risk of moderate/severe dengue, initially with modest performance (AUC ~ 0.68), but improving subsequently as new daily data is included into the predictions (AUC ~ 0.73-0.85). We also demonstrate that using these models in combination with clinical decision-making pathways could facilitate earlier admission of high-risk patients without markedly increasing admissions of uncomplicated cases. These results should prove instrumental for updating guidelines on dengue triage and management, potentially providing major public health benefits in resource poor settings. Authors used laboratory tests and clinical symptoms to predict dengue progression in a multi-country study. Prediction models improved in accuracy over time, enabling earlier admission of high-risk patients without overwhelming hospital capacity.

Arthropod-borne (arbo)-viruses, especially dengue (DENV), Zika (ZIKV), chikungunya (CHIKV) and yellow fever virus (YFV) are a public health threat worldwide. Timely and reliable diagnostics are key for early case detection, proper patient management and targeted public health interventions. We developed, validated and implemented a real-time reverse transcription (RT)-PCR (ZYDC-PCR) for the simultaneous identification of these four arboviruses. The ZYDC-PCR was validated following MIQE guidelines, using Quality Control for Molecular Diagnostics (QCMD) and retrospective clinical samples at laboratories in Belgium (n = 44) and Cuba (n = 97). These samples consisted of samples positive for ZIKV (n = 9), CHIKV (n = 11), DENV1 (n = 8), DENV2 (n = 5), DENV3 (n = 26) and DENV4 (n = 47), as well as 14 negative endemic controls from DRC, Oropouche virus (OROV) positive (n = 9) and samples negative for DENV and OROV (n = 10). The ZYDC-PCR was implemented for an exploratory study in the Democratic Republic of the Congo (DRC), with 725 samples tested in total, in DRC (n = 621), in Antwerp (n = 104) and in both laboratories (n = 99). Extractions and PCRs were done with commercially available kits. The results for the technical validation were satisfactory. Detection limits were 11,760 copies (cp)/mL for ZIKV, 1510 cp/mL for CHIKV, 2330 cp/mL for DENV1, and 6800 cp/mL for YFV. For 15 samples (4 ZIKV, 1 CHIKV, 3 DENV1, 1 DENV2, 6 DENV3) with Cq values > 36.5 in the simplex-PCR, the multiplex ZYDC-PCR tested negative. Specificity for cross reactivity samples and retrospective samples tested in Belgium and Cuba was 100

Background:A major dengue outbreak was reported by the Cuban Ministry of Health in 2022, highlighting the need for strong surveillance, with high pediatric cases showing warning signs. Using phylogenetic and epidemiologic approaches, we provide evidence toward a better understanding of dengue's recent transmission history. Methods:This study details the implementation of the genomic surveillance system for Dengue virus. Pre-screened DENV-3 positive samples (reverse transcription-polymerase chain reaction [RT-PCR] cycle threshold [Ct] <30) with epidemiologic metadata-including symptom onset, sample collection date, sex, age, residence, symptoms, and disease classification-underwent whole genome sequencing using Nanopore technology. Results:Genome sequences from 2022 to 2023 confirmed DENV-3 genotype III circulation in western, central, and eastern Cuba, covering 15 provinces and one special municipality. All cases were autochthonous, with 93% classified as dengue without warning signs and 7% as severe dengue. Long-term analysis identified a seasonal window of heightened suitability from May to November. Phylogenetic analyses revealed that DENV-3 genotype III has been introduced into Cuba multiple times, primarily from Asia and the Americas. These independent introduction events, likely driven by international travel and trade, underscore the importance of continued viral importation monitoring. The newly sequenced Cuban DENV-3 genotype III genomes were assigned to two distinct sub-lineages within genotype III: 3III_C, corresponding to the older American lineage I (2001-2014), and 3III_B.3, representing a novel introduction into Cuba associated with the more recent American lineage II (2022-2023). Evidence suggests that 3III_C, previously circulating in the country, may have been replaced by 3III_B.3 around 2020. Conclusions:This study outlines the development of a dengue genomic monitoring system in the country. The system will contribute to Cuba's public health response, facilitating timely interventions and potentially reducing the disease's impact on the local population.

Identify the genotype of the Dengue 3 virus circulating in Cuba in 2022. Brazil, Costa Rica and the United States reported the circulation of a new lineage of the Dengue 3 genotype lll, lineage American II. Four serum samples of DENV-3 collected in 2022 were partially sequenced in a fragment that encodes the envelope gene. Obtained sequences were compared with Cuban sequences from previous years and with others published at GenBank of genotypes I, II and III. Cuban samples of 2022 were classified as genotype III, American lineage II while the previous Cuban isolates were classified as genotype III, American lineage I. The obtained results constitute the basis for future studies using next generation sequencing that will improve our knowledge on this new lineage and its impact on virus transmission and disease severity.

Oropouche virus (OROV) was reported in Cuba in May 2024 and rapidly spread throughout the country. Among 147 RT-PCR-positive cases identified from May to July, we generated 39 whole-genome sequences. Phylogenetic analysis revealed that all sequences formed a monophyletic cluster nested within the novel reassortant OROVBR-2015-2025, which has been circulating extensively in Brazil since the end of 2023. Additional analyses demonstrated that the Cuban sub-clade originated from a single viral introduction from the Brazilian state of Acre, probably in early February 2024, and circulated cryptically until its identification in May. The introduction likely occurred in the Central region of the country, from which the virus spread and established secondary transmission hubs in the Western and Eastern regions. These findings underscore the capacity of OROV to spread well beyond the Amazon region, which was considered its endemic area of circulation.

For diseases with epidemic potential, specimen and data sharing is crucial for sustained research and development of medical countermeasures such as diagnostics, therapeutics, and vaccines. In the case of Zika virus, although a global framework for specimen and data sharing to advance research and development is highly desirable, challenges related to legal, ethical, and intellectual property issues persist. Since the 2015-16 Zika virus outbreak, regional laboratory networks and research partnerships have made some progress in specimen and data sharing among some Zika virus-endemic countries. Pragmatic steps such as securing funds for augmenting laboratory capacity, building biobanks within public health laboratory infrastructures in low-income and middle-income countries, clearly defining the specimens and data that need to be collected, developing standardised protocols, harmonising data system interoperability to facilitate sharing, and defining mechanisms for benefit sharing will pave the way for timely development and deployment of medical countermeasures in public health emergencies.

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.

Este artigo tem como objetivo apresentar as medidas fiscais dos governos locais em resposta aos efeitos econômicos da COVID-19, apresentando reflexões relativas aos diferentes contextos do México e do Brasil. Para isso, foi realizada uma pesquisa qualitativa, com base nos dados abertos do governo do Brasil. e México, sendo avaliados 58 estados, 27 estados brasileiros e 31 estados do México. As informações coletadas foram analisadas por meio do software Iramuteq 2.0. Os resultados revelaram que, em ambos os países, os estados adotaram diferentes medidas em respostas aos impactos do COVID-19, em que se destaca o México que adotou: prorrogações e medidas de negociação do imposto sobre veículos, desconto de 100% no imposto sobre veículos na compra de veículos usados, redução do imposto de hospedagem para estados turísticos, isenção de 100% do imposto sobre habitação e incentivos para o pagamento de despesas com trabalhadores. No Brasil, foram adotadas diversas medidas de incentivos fiscais entre os estados, tais como: isenções fiscais, prorrogações e parcelamentos a todos os tributos. A pesquisa permite discutir estratégias direcionadas à identificação das medidas adotadas nos governos estaduais dos países, tendo como limitação a adoção de instrumentos necessários para discutir a recuperação das economias locais e finanças públicas.

The study aimed to investigate the role of regulatory/pro-inflammatory mediators in the immunopathogenesis of Zika infection by analyzing mRNA expression kinetics in PMBC of ZIKV-infected patients. Blood samples were collected from patients at the “Pedro Kouri” Institute of Tropical Medicine between January and July 2017. RT-PCR was used to determine mRNA levels of immune mediators IL-10, IL-15, IL-17, TNF-α, MIP-1α, RANTES, FOXP3, IP-10, and TGF-β in PBMC. Results showed low levels of pro-inflammatory mediators and high levels of regulatory cytokines during acute and convalescent ZIKV phases, with a significant association between MIP-1α, IL-15, and IL-10 levels and joint pain. These findings suggest that regulatory cytokine mRNA levels may contribute to evading the antiviral immune response, shedding light on Zika's pathogenic mechanisms. The study also highlights the link between elevated IL-15 mRNA levels and joint pain.

Purpose:Oxysterol-binding protein-like 10 (OSBPL10) gene has been associated with reduced susceptibility to severe dengue in individuals of African descent. The aim of this study was to determine the possible effect of OSBPL10 on dengue virus (DENV) replication as well as the impact of African and European haplotypes of six OSBPL10 small nuclear polymorphisms (SNPs) on dengue multiplication and innate immune response. Methods:We conducted gene knockdown experiments targeting OSBPL10 in THP-1 and Huh-7D12 cell lines, followed by a DENV-2 replication assay. Extracellular viral load was determined using qRT-PCR. To investigate the impact of SNPs haplotypes on viral replication and gene expression we cultured peripheral blood mononuclear cells (PBMC) from individuals with homozygous African and European haplotypes of OSBPL10 with DENV-2. Individual genotyping was performed using High Resolution Melt (HRM) analysis. The level of viral replication was assessed through plaque assay, while RT-PCR was employed to determine the expression levels of RXR-α, IFN-γ, IL-10 and IL-8 genes. Results:In vitro OSBPL10 knockdown significantly reduced DENV-2 replication. Individuals carrying European haplotypes showed higher DENV titers along with elevated levels of RXR-α and IL-8 mRNA compared to those carrying African haplotypes, who exhibited lower viral loads alongside increased IFN-γ and IL-10 expression. Conclusions:Our findings further explore the role of OSBPL10 in DENV multiplication, immune response to infection. The European haplotypes of OSBPL10 appear to increase DENV replication and promote RXR-α and IL-8 mRNA expression which correlates with the suppressive effect of these mediators on type I IFN, promoting viral replication and a deficient antiviral response. In contrast, the African haplotype showed a reduction in DENV replication and enhanced IFN-γ and IL-10 mRNA expression, which could be related to the better management of dengue infection and the low frequency of severe disease in this ethnic groupe.

Several anti-Covid-19 vaccines have been developed corresponding to at least 11 vaccine platforms, including novel technology. The Abdala vaccine is based on the RBD fragment of the surface antigen of SARS-CoV-2 expressed in yeast. Previously, we demonstrated the immunogenicity of the recombinant antigen in animals. The present studies examined the impact of Abdala vaccination on the production of RBD-specific antibodies and their functional capacity using two immunization schedules (short 0-14-28 versus long 0-21-42) and two dose levels (10 and 50 µg) in rats and monkeys. The functional capacity of the antibody response was evaluated using an in vitro test to detect blocking antibodies to the ACE-2-RBD interaction and neutralizing activity versus the homologous Wuhan strain. For monkey sera, neutralization against variants of concern (VOC) beta (B.1.351), delta (B.1.617.2) and omicron (BA.1) was also evaluated. Taken together, the findings revealed previously unappreciated differences of the Abdala vaccine in the functional capacity of the antibody response according to the number of inoculations, the dose level, and the dose interval. In this regard, when using the short dose interval, three inoculations seem necessary to improve the functional antiviral response which is also favored with the higher dose level and a long dosing interval. The results in the NHP model also suggest that two doses using a long-time interval (0-21) could improve the efficacy of the Abdala vaccine compared to the short-interval regime (0-14). Cross-neutralization against variants of concern was also demonstrated.

The interferon-stimulated gene 15 (ISG15) is a ubiquitin-like modifier induced by type I Interferon (IFN-I) and plays a crucial role in the innate immune response against viral infections. ISG15 is conjugated to target proteins by an enzymatic cascade through a process called ISGylation. While ubiquitin-specific protease 18 (USP18) is a well-defined deISGylase counteracting ISG15 conjugation, ISG15 cross-reactive deubiquitylating enzymes (DUBs) have also been reported. Our study reports USP24 as a novel ISG15 cross-reactive DUB identified through activity-based protein profiling (ABPP). We demonstrate that recombinant USP24 processed pro-ISG15 and ISG15-linked synthetic substrates in vitro . Moreover, the depletion of USP24 significantly increased the accumulation of ISG15 conjugates upon IFN-β stimulation. An extensive proteomic analysis of the USP24-dependent ISGylome, integrating total proteome, GG-peptidome, and ISG15 interactome data, identified the helicase Moloney leukemia virus 10 (MOV10) as a specific target of USP24 for deISGylation. Further validation in cells revealed that ISGylated MOV10 enhances IFN-β production/secretion, whereas USP24 deISGylates MOV10 to negatively regulate the innate immune response. This study showcases USP24’s novel roles in modulating ISGylation and modulation of the IFN-I-dependent immune responses, with potential therapeutic implications in infectious diseases, cancer, autoimmunity, and neuroinflammation. ### Competing Interest Statement The authors have declared no competing interest.

Dengue illness, caused by the dengue viruses, continues to be a major global health concern, with increasing incidence and the emergence of severe manifestations such as neurological complications. An overview of the current understanding of dengue epidemiology, clinical manifestations, and research priorities is presented here. Dengue transmission has escalated in recent years, exacerbated by factors such as vector expansion, climate change, and socioeconomic challenges. The clinical spectrum of dengue ranges from mild febrile illness to severe manifestations, including hemorrhagic fever and neurological complications. Neurological manifestations of dengue, once considered rare, are now increasingly reported, encompassing encephalitis, myelitis, and Guillain–Barré Syndrome, among others. Diagnosis primarily relies on laboratory methods such as RT/PCR, NS1 antigen detection, and serological assays. Despite advancements in understanding the dengue pathogenesis, there remains a critical need for effective vaccines, antiviral drugs, improved surveillance methods, predictive models for disease severity, and long-term studies on post-Dengue sequelae. Integrated programs and holistic approaches to dengue control are essential for mitigating its impact. Addressing these research priorities will be pivotal in combating dengue and reducing its global burden.