Live, Attenuated, Tetravalent Butantan-Dengue Vaccine in Children and Adults.

BACKGROUND: Butantan-Dengue Vaccine (Butantan-DV) is an investigational, single-dose, live, attenuated, tetravalent vaccine against dengue disease, but data on its overall efficacy are needed. METHODS: In an ongoing phase 3, double-blind trial in Brazil, we randomly assigned participants to receive Butantan-DV or placebo, with stratification according to age (2 to 6 years, 7 to 17 years, and 18 to 59 years); 5 years of follow-up is planned. The objectives of the trial were to evaluate overall vaccine efficacy against symptomatic, virologically confirmed dengue of any serotype occurring more than 28 days after vaccination (the primary efficacy end point), regardless of serostatus at baseline, and to describe safety up to day 21 (the primary safety end point). Here, vaccine efficacy was assessed on the basis of 2 years of follow-up for each participant, and safety as solicited vaccine-related adverse events reported up to day 21 after injection. Key secondary objectives were to assess vaccine efficacy among participants according to dengue serostatus at baseline and according to the dengue viral serotype; efficacy according to age was also assessed. RESULTS: Over a 3-year enrollment period, 16,235 participants received either Butantan-DV (10,259 participants) or placebo (5976 participants). The overall 2-year vaccine efficacy was 79.6% (95% confidence interval [CI], 70.0 to 86.3) - 73.6% (95% CI, 57.6 to 83.7) among participants with no evidence of previous dengue exposure and 89.2% (95% CI, 77.6 to 95.6) among those with a history of exposure. Vaccine efficacy was 80.1% (95% CI, 66.0 to 88.4) among participants 2 to 6 years of age, 77.8% (95% CI, 55.6 to 89.6) among those 7 to 17 years of age, and 90.0% (95% CI, 68.2 to 97.5) among those 18 to 59 years of age. Efficacy against DENV-1 was 89.5% (95% CI, 78.7 to 95.0) and against DENV-2 was 69.6% (95% CI, 50.8 to 81.5). DENV-3 and DENV-4 were not detected during the follow-up period. Solicited systemic vaccine- or placebo-related adverse events within 21 days after injection were more common with Butantan-DV than with placebo (58.3% of participants, vs. 45.6%). CONCLUSIONS: A single dose of Butantan-DV prevented symptomatic DENV-1 and DENV-2, regardless of dengue serostatus at baseline, through 2 years of follow-up. (Funded by Instituto Butantan and others; DEN-03-IB ClinicalTrials.gov number, NCT02406729, and WHO ICTRP number, U1111-1168-8679.).

HR-MAS NMR Metabolomics Profile of Vero Cells under the Influence of Virus Infection and nsP2 Inhibitor: A Chikungunya Case Study.

The arbovirus Chikungunya (CHIKV) is transmitted by Aedes mosquitoes in urban environments, and in humans, it triggers debilitating symptoms involving long-term complications, including arthritis and Guillain-Barré syndrome. The development of antiviral therapies is relevant, as no efficacious vaccine or drug has yet been approved for clinical application. As a detailed map of molecules underlying the viral infection can be obtained from the metabolome, we validated the metabolic signatures of Vero E6 cells prior to infection (CC), following CHIKV infection (CV) and also upon the inclusion of the nsP2 protease inhibitor wedelolactone (CWV), a coumestan which inhibits viral replication processes. The metabolome groups evidenced significant changes in the levels of lactate, myo-inositol, phosphocholine, glucose, betaine and a few specific amino acids. This study forms a preliminary basis for identifying metabolites through HR-MAS NMR (High Resolution Magic Angle Spinning Nuclear Magnetic Ressonance Spectroscopy) and proposing the affected metabolic pathways of cells following viral infection and upon incorporation of putative antiviral molecules.

Exploring Iguape Virus-A Lesser-Known Orthoflavivirus.

Brazil has earned the moniker "arbovirus hotspot", providing an ideal breeding ground for a multitude of arboviruses thriving in various zoonotic and urban cycles. As the planet warms and vectors expand their habitat range, a nuanced understanding of lesser-known arboviruses and the factors that could drive their emergence becomes imperative. Among these viruses is the Iguape virus (IGUV), a member of the Orthoflavivirus aroaense species, which was first isolated in 1979 from a sentinel mouse in the municipality of Iguape, within the Vale do Ribeira region of São Paulo State. While evidence suggests that IGUV circulates among birds, wild rodents, marsupials, bats, and domestic birds, there is no information available on its pathogenesis in both humans and animals. The existing literature on IGUV spans decades, is outdated, and is often challenging to access. In this review, we have curated information from the known literature, clarifying its elusive nature and investigating the factors that may influence its emergence. As an orthoflavivirus, IGUV poses a potential threat, which demands our attention and vigilance, considering the serious outbreaks that the Zika virus, another neglected orthoflavivirus, has unleashed in the recent past.

Beyond Borders: Investigating the Mysteries of Cacipacoré, a Lesser-Studied Arbovirus in Brazil.

Cacipacoré virus (CPCV) was discovered in 1977 deep in the Amazon rainforest from the blood of a black-faced ant thrush (Formicarius analis). As a member of the family Flaviviridae and genus orthoflavivirus, CPCV's intricate ecological association with vectors and hosts raises profound questions. CPCV's transmission cycle may involve birds, rodents, equids, bovines, marsupials, non-human primates, and bats as potential vertebrate hosts, whereas Culex and Aedes spp. mosquitoes have been implicated as potential vectors of transmission. The virus' isolation across diverse biomes, including urban settings, suggests its adaptability, as well as presents challenges for its accurate diagnosis, and thus its impact on veterinary and human health. With no specific treatment or vaccine, its prevention hinges on traditional arbovirus control measures. Here, we provide an overview of its ecology, transmission cycles, epidemiology, pathogenesis, and prevention, aiming at improving our ability to better understand this neglected arbovirus.

A meta-analysis of Chikungunya virus in neurological disorders.

Chikungunya disease typically presents with the fever-arthralgia-rash symptom triad. However, an increase in the number of atypical clinical manifestations, particularly neurological disorders, has occurred. The current evidence regarding the pooled prevalence of Chikungunya virus (CHIKV)-associated neurological cases (CANCs) suspected of having an arboviral aetiology is not well-understood. Therefore, this meta-analysis included 19 studies (n = 7319 patients) and aimed to determine the pooled rate of exposure to CANC. The pooled positivity rate of CANC was 12 % (95 % CI: 6-19), and Brazil was overrepresented (11/19). These estimations varied between 3 and 14 % based on the diagnostic method (real-time PCR vs. ELISA-IgM) and biological samples (cerebrospinal fluid or blood specimens) used for detection of CHIKV. Regarding the frequency of CHIKV in neurological clinical subgroups, the rates were higher among patients with myelitis (27 %), acute disseminated encephalomyelitis (27 %), Guillain-Barré syndrome (15 %), encephalitis (12 %), and meningoencephalitis (7 %). Our analysis highlights the significant burden of CANC. However, the data must be interpreted with caution due to the heterogeneity of the results, which may be related to the location of the studies covering endemic periods and/or outbreaks of CHIKV. Current surveillance resources should also focus on better characterizing the epidemiology of CHIKV infection in neurological disorders. Additionally, future studies should investigate the interactions between CHIKV and neurological diseases with the aim of gaining deeper insight into the mechanisms underlying the cause-and-effect relationship between these two phenomena.

Potential of Ilhéus virus to emerge.

Ilhéus virus (ILHV)(Flaviviridae:Orthoflavivirus) is an arthropod-borne virus (arbovirus) endemic to Central and South America and the Caribbean. First isolated in 1944, most of our knowledge derives from surveillance and seroprevalence studies. These efforts have detected ILHV in a broad range of mosquito and vertebrate species, including humans, but laboratory investigations of pathogenesis and vector competence have been lacking. Here, we develop an immune intact murine model with several ages and routes of administration. Our model closely recapitulates human neuroinvasive disease with ILHV strain- and mouse age-specific virulence, as well as a uniformly lethal Ifnar-/- A129 immunocompromised model. Replication kinetics in several vertebrate and invertebrate cell lines demonstrate that ILHV is capable of replicating to high titers in a wide variety of potential host and vector species. Lastly, vector competence studies provide strong evidence for efficient infection of and potential transmission by Aedes species mosquitoes, despite ILHV's phylogenetically clustering with Culex vectored flaviviruses, suggesting ILHV is poised for emergence in the neotropics.

Diabetes as risk factor to severity of dengue in naïve patients.

Background: Dengue cases can progress to severe ant life-threating forms particularly in subsequent heterologous infections. However, recent studies had explored additional risk factors, including underlying health conditions, even in individuals without prior exposure to dengue, notably, in patients with endothelial dysfunction and chronic inflammation. This study examines the link between diabetes and the development of severe dengue disease in dengue-naive patients during the 2019 dengue outbreak in São Jose do Rio Preto, Brazil. Methodology: We enrolled 529 laboratory-confirmed dengue cases, identified through DENV RT-PCR or NS1 antigen assays in a hospital cohort of acute febrile illness. Subsequently, we investigated the presence of anti-dengue and anti-Zika IgG antibodies. Samples testing positive for Zika were excluded from the analyses. Two groups were analyzed: naïve (DV-), and dengue history (DV+). Results: Initially, presence of diabetes and kidney disease, as well as being dengue-naive, were associated with a higher frequency of severe and potentially severe clinical outcomes. Multivariate analysis identified diabetes as a risk factor, while the presence of anti-dengue antibodies was considered protective. Analysis of dengue naïve samples, highlighted diabetes as an independent risk factor to severe forms of dengue disease. In DV+ patients, no condition was highlighted as a risk factor by univariate analysis or multivariate analysis. Conclusions: We investigated and confirmed diabetes as a risk factor for severe dengue disease in individuals without prior dengue or Zika exposure. Our conclusions raise significant concerns given diabetes' ever increasing global prevalence and its potential impact on patients with or previous dengue exposure.

Second booster dose improves antibody neutralization against BA.1, BA.5 and BQ.1.1 in individuals previously immunized with CoronaVac plus BNT162B2 booster protocol.

Introduction: SARS-CoV-2 vaccines production and distribution enabled the return to normalcy worldwide, but it was not fast enough to avoid the emergence of variants capable of evading immune response induced by prior infections and vaccination. This study evaluated, against Omicron sublineages BA.1, BA.5 and BQ.1.1, the antibody response of a cohort vaccinated with a two doses CoronaVac protocol and followed by two heterologous booster doses. Methods: To assess vaccination effectiveness, serum samples were collected from 160 individuals, in 3 different time points (9, 12 and 18 months after CoronaVac protocol). For each time point, individuals were divided into 3 subgroups, based on the number of additional doses received (No booster, 1 booster and 2 boosters), and a viral microneutralization assay was performed to evaluate neutralization titers and seroconvertion rate. Results: The findings presented here show that, despite the first booster, at 9m time point, improved neutralization level against omicron ancestor BA.1 (133.1 to 663.3), this trend was significantly lower for BQ.1.1 and BA.5 (132.4 to 199.1, 63.2 to 100.2, respectively). However, at 18m time point, the administration of a second booster dose considerably improved the antibody neutralization, and this was observed not only against BA.1 (2361.5), but also against subvariants BQ.1.1 (726.1) and BA.5 (659.1). Additionally, our data showed that, after first booster, seroconvertion rate for BA.5 decayed over time (93.3% at 12m to 68.4% at 18m), but after the second booster, seroconvertion was completely recovered (95% at 18m). Discussion: Our study reinforces the concerns about immunity evasion of the SARS-CoV-2 omicron subvariants, where BA.5 and BQ.1.1 were less neutralized by vaccine induced antibodies than BA.1. On the other hand, the administration of a second booster significantly enhanced antibody neutralization capacity against these subvariants. It is likely that, as new SARS-CoV-2 subvariants continue to emerge, additional immunizations will be needed over time.

Clinical and epidemiological characteristics of Madariaga and Venezuelan equine encephalitis virus infections.

Madariaga virus (MADV) and Venezuelan equine encephalitis virus (VEEV) are emerging arboviruses affecting rural and remote areas of Latin America. However, there are limited clinical and epidemiological reports available, and outbreaks are occurring at an increasing frequency. We addressed this gap by analyzing all the available clinical and epidemiological data of MADV and VEEV infections recorded since 1961 in Panama. A total of 168 of human alphavirus encephalitis cases were detected in Panama from 1961 to 2023. Here we describe the clinical signs and symptoms and epidemiological characteristics of these cases, and also explored signs and symptoms as potential predictors of encephalitic alphavirus infection when compared to those of other arbovirus infections occurring in the region. Our results highlight the challenges clinical diagnosis of alphavirus disease in endemic regions with overlapping circulation of multiple arboviruses.

Efficacy and safety of Butantan-DV in participants aged 2-59 years through an extended follow-up: results from a double-blind, randomised, placebo-controlled, phase 3, multicentre trial in Brazil.

BACKGROUND: A single-dose dengue vaccine that protects individuals across a wide age range and regardless of dengue serostatus is an unmet need. We assessed the safety and efficacy of the live, attenuated, tetravalent Butantan-dengue vaccine (Butantan-DV) in adults, adolescents, and children. We previously reported the primary and secondary efficacy and safety endpoints in the initial 2 years of follow-up. Here we report the results through an extended follow-up period, with an average of 3·7 years of follow-up. METHODS: In this double-blind, randomised, placebo-controlled, phase 3, multicentre trial in Brazil, healthy participants (aged 2-59 years) who had not previously received a dengue vaccine were enrolled and randomly assigned 2:1 (stratified by age 18-59 years, 7-17 years, and 2-6 years) using a central electronic randomisation system to receive 0·5 mL of Butantan-DV (containing approximately 103 plaque-forming units of each of the four vaccine virus strains) or placebo, administered subcutaneously. Syringes containing vaccine or placebo were prepared by an unmasked trial pharmacist who was not involved in any subsequent participant assessments; other site staff and the participants remained unaware of the group allocations. Vaccine efficacy was calculated with the accrual of virologically confirmed dengue (VCD) cases (by RT-PCR) at least 28 days after vaccination up until the cutoff (at least 2 years of follow-up from the last participant enrolled). The primary endpoint was vaccine efficacy against VCD after day 28 by any dengue virus (DENV) serotype regardless of dengue serostatus at baseline in the per-protocol population. The primary and secondary safety endpoints up until day 21 were previously reported; secondary safety endpoints include the frequency of unsolicited vaccine-related adverse events after day 22. Safety analyses were done on all participants as treated. This trial is registered with ClinicalTrials.gov (NCT02406729) and is ongoing. FINDINGS: Of 16 363 participants assessed for eligibility, 16 235 were randomly assigned between Feb 22, 2016, and July 5, 2019, and received single-dose Butantan-DV (10 259 participants) or placebo (5976 participants). 16 162 participants (Butantan-DV n=10 215; placebo n=5947) were included in the per-protocol population and 16 235 (Butantan-DV n=10 259; placebo n=5976) in the safety population. At the data cutoff (July 13, 2021), participants had 2-5 years of follow-up (mean 3·7 years [SD 1·0], median 4·0 years [IQR 3·2-4·5]). 356 VCD cases were captured through the follow-up (128 in the vaccine group and 228 in the placebo group). Vaccine efficacy against VCD caused by any DENV serotype was 67·3% (95% CI 59·4-73·9); cases caused by DENV-3 or DENV-4 were not observed. The proportions of participants who had serious adverse events were similar between treatment groups (637 [6·2%] in the vaccine group and 395 [6·6%] in the placebo group) up until the cutoff. INTERPRETATION: A single dose of Butantan-DV was generally well tolerated and efficacious against symptomatic VCD (caused by DENV-1 and DENV-2) for a mean of 3·7 years. These findings support the continued development of Butantan-DV to prevent dengue disease in children, adolescents, and adults regardless of dengue serostatus. FUNDING: Instituto Butantan and Merck Sharp & Dohme LLC, a subsidiary of Merck & Co. TRANSLATIONS: For the Spanish and Portuguese translations of the abstract see Supplementary Materials section.

Genomic detection of a virus lineage replacement event of dengue virus serotype 2 in Brazil, 2019

BACKGROUND Despite efforts to mitigate the impact of dengue virus (DENV) epidemics, the virus remains a public health problem in tropical and subtropical regions around the world. Most DENV cases in the Americas between January and July 2019 were reported in Brazil. São Paulo State in the southeast of Brazil has reported nearly half of all DENV infections in the country. OBJECTIVES To understand the origin and dynamics of the 2019 DENV outbreak. METHODS Here using portable nanopore sequencing we generated20 new DENV genome sequences from viremic patients with suspected dengue infection residing in two of the most-affected municipalities of São Paulo State, Araraquara and São José do Rio Preto. We conducted a comprehensive phylogenetic analysis with 1,630 global DENV strains to better understand the evolutionary history of the DENV lineages that currently circulate in the region. FINDINGS The new outbreak strains were classified as DENV2 genotype III (American/Asian genotype). Our analysis shows that the 2019 outbreak is the result of a novel DENV lineage that was recently introduced to Brazil from the Caribbean region. Dating phylogeographic analysis suggests that DENV2-III BR-4 was introduced to Brazil in or around early 2014, possibly from the Caribbean region. MAIN CONCLUSIONS Our study describes the early detection of a newly introduced and rapidly-expanding DENV2 virus lineage in Brazil.

Hereditary thrombophilia by factor V Leiden G1691A (heterozygous) and FII prothrombin G20210A (homozygous) mutations in a patient with ischemic cerebrovascular accident / Trombofilia hereditária por mutações G1691A do fator V Leiden (heterozigota) e G20210A do FII protrombina (homozigota) em paciente com acidente vascular cerebral isquêmico

ABSTRACT Mutations related to Factor V Leiden (G1691A) and prothrombin (G20210A) are associated with a significantly increased risk of venous thromboembolism. The identification of a patient affected by episodes of venous thromboembolism and carrier of G1691A (heterozygous) and G20210A (homozygous) polymorphisms was determined by molecular tests [real-time polymerase chain reaction (PCR) methodology, Genexpert system] during attendance at the Base Hospital of São José do Rio Preto-SP, Brazil.

RESUMO Mutações relacionadas com o fator V de Leiden (G1691A) e a protrombina (G20210A) estão associadas a um significativo aumento do risco de tromboembolismo venoso. Por meio da realização de exames moleculares [metodologia de reação em cadeia da polimerase (PCR) em tempo real, sistema Genexpert], em pacientes atendidos no Hospital de Base de São José do Rio Preto-SP, Brasil, foi determinada a identificação de uma paciente afetada por episódios de tromboembolismo venoso e portadora dos polimorfismos G1691A (heterozigota) e G20210A (homozigota).