• MCDM
• TOPSIS
• Type-2 heptagonal fuzzy number
• Type-2 heptagonal fuzzy set
• VIKOR
• WASPAS

• Zika Virus Infection/epidemiology
• Humans
• Zika Virus
• Fuzzy Logic
• Risk Factors
• Risk Assessment/methods
• Decision Making
• Female
• Reproducibility of Results

• Vellore Institute of Technology, Chennai

• Aedes aegypti
• Asia
• arboviruses
• infection
• insecticide resistance
• kdr
• mosquito
• yellow fever

• 316730/2021-1 CNPq
• E-26/204.210/2024 FAPERJ

• Cross-reactivity
• IgG avidity
• Reverse transcription-polymerase chain reaction
• Serology
• West Nile virus

• Zika
• adeno-associated virus
• dengue
• mimotope
• vaccine

• Humans
• Zika Virus
• Zika Virus Infection/prevention & control
• Dengue Virus/chemistry
• Dengue/prevention & control
• Antibodies, Viral
• Viral Envelope Proteins/chemistry
• Antibodies, Neutralizing
• Vaccines
• Epitopes
• Cross Reactions

• Chikungunya
• IgG
• Zika
• dengue
• enzyme-linked immunosorbent assay
• neutralization assays

• Animals
• Female
• Pregnancy
• Zika Virus Infection
• Zika Virus
• Callithrix
• Antibodies, Neutralizing
• Antibodies, Viral
• Endothelial Cells
• Dengue Virus
• Dengue
• Placenta
• Cross Reactions

• K12 HD052023 NICHD NIH HHS
• P51 OD011133 NIH HHS
• S10 OD028732 NIH HHS

• drug discovery
• microbiology
• molecular biology

• Animals
• Mice
• Zika Virus
• Dengue Virus
• Dengue/drug therapy
• Zika Virus Infection
• Mice, Inbred C57BL
• Flavivirus

• Ratchadapiseksompotch Research fund, Faculty of Medicine, Chulalongkorn University
• National Research Council of Thailand

• Adult
• Humans
• Yellow Fever Vaccine
• Dengue Vaccines
• Dengue
• Yellow Fever/prevention & control
• Vaccines, Combined
• Antibodies, Viral
• Immunogenicity, Vaccine
• Vaccines, Attenuated

• Takeda Vaccines, Inc., Boston, MA, USA

Zika virus (ZIKV) is a mosquito-borne flavivirus whose infection in pregnant women is associated with a spectrum of birth defects, which are together referred as Congenital Zika Syndrome. In addition, ZIKV can also induce Guillain–Barré syndrome, which is an autoimmune disease with neurological symptoms. The recent description of the first local infections of ZIKV in the European continent together with the expansion of one of its potential vectors, the Asian tiger mosquito (Aedes albopictus), invite us to be prepared for future outbreaks of ZIKV in this geographical region. However, the antigenic similarities of ZIKV with other flaviviruses can lead to an immune cross-reactivity with other circulating flaviviruses inducing, in some cases, flavivirus-disease exacerbation by antibody-dependent enhancement (ADE) of infection, which is a major concern for ZIKV vaccine development. Until now, West Nile virus (WNV) is the main medically relevant flavivirus circulating in the Mediterranean Basin. Therefore, anticipating the potential scenario of emergency vaccination against ZIKV in areas of Europe where WNV is endemic, in this investigation, we have evaluated the cross-reactivity between WNV and our previously developed ZIKV vaccine candidate based on modified vaccinia virus Ankara (MVA) vector expressing ZIKV structural proteins (MVA-ZIKV). To this end, mice were first immunized with MVA-ZIKV, subsequently challenged with WNV, and then, the ZIKV- and WNV-specific immune responses and protection against WNV were evaluated. Our results indicate low cross-reactivity between the MVA-ZIKV vaccine candidate and WNV and absence of ADE, supporting the safety of this ZIKV vaccine candidate in areas where the circulation of WNV is endemic.

Arboviruses primarily consist of RNA, which favours greater genetic plasticity, with a higher frequency of mutations that allow the virus to adapt to different hosts. The initial symptomatology is nonspecific, in that the patient can present fever, myalgia, arthralgia, rash and headache. This makes a clinical diagnosis using laboratory tests difficult and time-consuming. In Brazil, the main arboviruses involved in epidemics belong to the family Flaviviridae. The patient in this case is from the municipality of São Bernardo do Campo, an area endemic for arboviruses. He presented symptoms of fever, myalgia and headache.

The multiplex assay for arboviruses detected genetic material from the dengue 2 and yellow fever viruses.

This result confirms the importance of molecular tests showing high sensitivity and specificity that can assist clinical diagnosis, particularly in endemic areas during periods of outbreak for other arboviruses, like the epidemiological picture in Brazil in 2018, when significant co-circulation of dengue virus and yellow fever virus occurred. The presence of co-circulating arboviruses increases the chance of coinfection and demonstrates the importance of differential diagnosis.

• arbovirus infections and diagnosis
• coinfection

• antibody epitopes
• antibody evolution
• dengue
• flavivirus
• peptide microarray

• Adolescent
• Adult
• Antibodies, Viral/blood
• Antibodies, Viral/immunology
• Belgium
• Cross Reactions/immunology
• Dengue/blood
• Dengue/immunology
• Dengue Virus/genetics
• Dengue Virus/immunology
• Enzyme-Linked Immunosorbent Assay
• Epitopes/chemistry
• Epitopes/immunology
• Female
• Flavivirus/immunology
• Humans
• Immunoglobulin G/blood
• Immunoglobulin G/immunology
• Immunoglobulin M/blood
• Immunoglobulin M/immunology
• Male
• Middle Aged
• Peru
• Serologic Tests
• Travel
• Young Adult

Because of limited data on dengue virus in Burkina Faso, we conducted 4 consecutive age-stratified longitudinal serologic surveys, ≈6 months apart, among persons 1–55 years of age, during June 2015–March 2017, which included a 2016 outbreak. The seroconversion rate before the serosurvey enrollment was estimated by binomial regression, taking age as the duration of exposure, and assuming constant force of infection (FOI) over age and calendar time. We calculated FOI between consecutive surveys and rate ratios for potentially associated characteristics based on seroconversion using the duration of intervals. Among 2,897 persons at enrollment, 66.3% were IgG-positive, and estimated annual FOI was 5.95%. Of 1,269 enrollees participating in all 4 serosurveys, 438 were IgG-negative at enrollment. The annualized FOI ranged from 10% to 20% (during the 2016 outbreak). Overall, we observed high FOI for dengue. These results could support decision-making about control and preventive measures for dengue.

• Aedes mosquitoes
• Africa
• Burkina Faso
• IgG
• cross reactivity
• dengue
• flaviviruses
• force of infection
• outbreaks
• population seroprevalence
• regression models
• seroconversion
• viruses

• Burkina Faso/epidemiology
• Child, Preschool
• Dengue/epidemiology
• Dengue Virus
• Disease Outbreaks
• Humans
• Infant

• MR/R010161/1 Medical Research Council
• ROH-115213 CIHR

After the Zika virus (ZIKV) epidemic in the Americas in 2016, both Zika and dengue incidence declined to record lows in many countries in 2017–2018, but in 2019 dengue resurged in Brazil, causing ~2.1 million cases. In this study we use epidemiological, climatological and genomic data to investigate dengue dynamics in recent years in Brazil. First, we estimate dengue virus force of infection (FOI) and model mosquito-borne transmission suitability since the early 2000s. Our estimates reveal that DENV transmission was low in 2017–2018, despite conditions being suitable for viral spread. Our study also shows a marked decline in dengue susceptibility between 2002 and 2019, which could explain the synchronous decline of dengue in the country, partially as a result of protective immunity from prior ZIKV and/or DENV infections. Furthermore, we performed phylogeographic analyses using 69 newly sequenced genomes of dengue virus serotype 1 and 2 from Brazil, and found that the outbreaks in 2018–2019 were caused by local DENV lineages that persisted for 5–10 years, circulating cryptically before and after the Zika epidemic. We hypothesize that DENV lineages may circulate at low transmission levels for many years, until local conditions are suitable for higher transmission, when they cause major outbreaks.

Zika and dengue incidence in the Americas declined in 2017–2018, but dengue resurged in 2019 in Brazil. This study uses epidemiological, climatological and genomic data to show that the decline of dengue may be explained by protective immunity from pre-exposure to ZIKV and/or DENV in prior years.

• Antibody-dependent infection enhancement
• Coronavirus
• Vaccine

Zika virus (ZIKV) is a flavivirus that originated in Africa but emerged in Latin America in 2015. In this region, other flaviviruses such as Dengue (DENV), West Nile, and Yellow Fever virus (YFV) also circulate, allowing for possible antigenic cross-reactivity to impact viral infections and immune responses. Studies have found antibody-mediated enhancement between DENV and ZIKV, but the impact of YFV antibodies on ZIKV infection has not been fully explored. ZIKV infections cause congenital syndromes, such as microcephaly, necessitating further research into ZIKV vertical transmission through the placental barrier. Recent advancements in biomedical engineering have generated co-culture methods that allow for the in vitro recapitulation of the maternal–fetal interface. This study utilized a transwell assay, which was a co-culture model utilizing human placental syncytiotrophoblasts, fetal umbilical cells, and a differentiating embryoid body, to replicate the maternal–fetal axis. To determine if cross-reactive YFV vaccine antibodies impacted the pathogenesis of ZIKV across the maternal–fetal axis, syncytiotrophoblasts were inoculated with ZIKV or ZIKV incubated with YFV vaccine antisera, and the viral load was measured 72 h post-inoculation. Here, we report that BeWo and HUVEC cells were permissive to ZIKV and that the impact of YFV post-vaccination antibodies on ZIKV replication was cell line-dependent. Embryoid bodies were also permissive to ZIKV, and the presence of YFV antibodies collected 4–14 months post-vaccination reduced ZIKV infection when placental cells were present. However, when directly infected with ZIKV, the embryoid bodies displayed significantly increased viral loads in the presence of YFV antiserum taken 30 days post-vaccination. The data show that each of the cell lines and EBs have a unique response to ZIKV complexed with post-vaccination serum, suggesting there may be cell-specific mechanisms that impact congenital ZIKV infections. Since ZIKV infections can cause severe congenital syndromes, it is crucial to understand any potential enhancement or protection offered from cross-reactive, post-vaccination antibodies.

• Zika congenital syndrome
• Zika virus
• congenital infections
• cross-reactivity
• enhancement
• flavivirus
• neutralization
• stem cell
• yellow fever virus

• COVID-19
• Cytokine
• Cytokine storm
• Immunology
• Inflammation
• Macrophage activation syndrome
• SARS-CoV-2
• Thrombosis

• Age Factors
• Angiotensin-Converting Enzyme 2
• Animals
• Antibody Formation
• Betacoronavirus/immunology
• Betacoronavirus/pathogenicity
• Blood Coagulation Disorders/etiology
• COVID-19
• Comorbidity
• Coronavirus Infections/blood
• Coronavirus Infections/complications
• Coronavirus Infections/epidemiology
• Coronavirus Infections/immunology
• Cytokine Release Syndrome/immunology
• Humans
• Immunity, Innate
• Inflammation/immunology
• Lung/pathology
• Lymphopenia/immunology
• Mice
• Middle East Respiratory Syndrome Coronavirus/immunology
• Pandemics
• Peptidyl-Dipeptidase A/physiology
• Pneumonia, Viral/blood
• Pneumonia, Viral/complications
• Pneumonia, Viral/epidemiology
• Pneumonia, Viral/immunology
• Respiratory Distress Syndrome/immunology
• Risk Factors
• SARS-CoV-2
• Severe Acute Respiratory Syndrome/immunology
• Severity of Illness Index
• Sex Factors
• Virus Internalization

Zika virus (ZIKV) is a positive-stranded RNA virus within the Flaviviridae family. After decades of circulation in Asia, ZIKV was introduced to Brazil in 2014–2015, associated with a rise in congenital malformations. Unlike the genetically related dengue virus (DENV), ZIKV constitutes only one serotype. Although assumed that ZIKV infection may engender lifelong immunity, the long-term kinetics of ZIKV antibody responses are unclear. We assessed long-term kinetics of ZIKV NS1-IgG response in 144 individuals from 3 different subpopulations: HIV patients, tuberculosis patients and healthy individuals first tested in 2016 and retested 1.5–2 years after the 2015–2016 ZIKV epidemic in Salvador de Bahia, Brazil, using a widely distributed NS1-based commercial ELISA. The seropositivity in 2016 reached 59.0% (85/144, 95% confidence interval (CI) 50.7–66.7%), and decreased to 38.6% (56/144, CI 31.3–47.0%) 1.5–2 years later. In addition, the median ZIKV NS1-ELISA reactivity for individuals that remained positive in both timepoints significantly decreased from a ratio of 4.4 (95% CI 3.8–5.0) to 1.6 (95% CI 1.6–1.9) over the 2-year interval (Z: − 6.1; p < 0.001) irrespective of the subpopulation analyzed. Initial 2016 DENV antibody response was non-significant between groups, suggesting comparable DENV background. The high 20.6% seroreversion suggest that widely used serologic tests may fail to account a considerable proportion of past ZIKV infections in flavivirus endemic countries. In addition, ZIKV immunity might be shorter-lived than previously thought, which may contribute to local ZIKV resurgence once individual immune responses wane sufficiently to reduce community protective immunity in addition to birth and migration.

• Antigens
• Flavivirus
• Serology
• Zika virus

• Covid-19
• SARS-CoV-2
• T cell repertoire
• antiviral immunity
• coronavirus
• cytokine storm
• immune response

Between 2016 and 2019, 265 cases of Zika virus (ZIKV) infection were reported in Vietnam, predominantly in southern Vietnam. In 2016, a case of ZIKV-associated microcephaly was confirmed in the Central Highlands, and several members of the infant’s family were confirmed to be infected with ZIKV. The study aims to determine the level of immunity to ZIKV in the general population of the ZIKV epidemic region.

A total of 879 serum samples were collected from 801 participants between January 2017 and July 2018, during and after the ZIKV epidemic in Vietnam. The samples were tested for anti-ZIKV immunoglobulin M (IgM) and immunoglobulin G (IgG), and anti-dengue virus (DENV) IgG antibodies using enzyme-linked immunosorbent assays (ELISA). Plaque-reduction neutralization test (PRNT) for ZIKV was performed on all samples, and for DENV on the samples that ZIKV neutralizing antibody positive.

A total of 83 (10.3%) participants had anti-ZIKV IgM. Of the 83, 6 were confirmed to be ZIKV antibodies positive using PRNT and anti-ZIKV IgG ELISA. Of the 718 participants who were anti-ZIKV IgM negative, a further 3 cases were confirmed as positive for antibodies against ZIKV. Of the 9 participants with ZIKV infection, 5 lived in the same village as the infant with ZIKV-associated microcephaly and the other 4 lived in 2 neighboring communes. Repeat samples were collected from the 83 ZIKV IgM positive participants 1.5 years after the first collection. No new cases of ZIKV infection were detected. In addition, 2 of 3 participants with anti-ZIKV NS1 IgG demonstrated a 4- to 8-fold increase in ZIKV neutralizing antibody titer.

ZIKV was present in the area around Krong Buk, with the rate of ZIKV-specific antibodies was 1.1% in the community since at least 2016. While the low levels of circulation together with low seroprevalence suggests a limited outbreak in the region, the results also reflect on low levels of protective immunity to Zika within the population. These results provide a better understanding of the current ZIKV epidemic status in the region and demonstrate a need for implementation of more effective ZIKV infection control measures.

• Neutralizing antibodies
• Seroepidemiologic studies
• Seroprevalence
• Vietnam
• Zika virus
• Zika virus infection

• chikungunya
• co-endemic
• coronavirus
• dengue
• zika

• B cell responses
• B cells
• B-1 cells
• extrafollicular responses
• germinal center responses
• immune regulation

• Antibody-dependent enhancement
• Dengue
• Importation
• Plaque reduction neutralization test
• Taiwan
• Zika

• acute febrile illness
• flavivirus
• mosquito-borne
• vaccine
• yellow fever

Yellow fever virus (YFV) represents a re-emerging zoonotic pathogen, transmitted by mosquito vectors to humans from primate reservoirs. Sporadic outbreaks of YFV occur in endemic tropical regions, causing a viral hemorrhagic fever (VHF) associated with high mortality rates. Despite a highly effective vaccine, no antiviral treatments currently exist. Therefore, YFV represents a neglected tropical disease and is chronically understudied, with many aspects of YFV biology incompletely defined including host range, host–virus interactions and correlates of host immunity and pathogenicity. In this article, we review the current state of YFV research, focusing on the viral lifecycle, host responses to infection, species tropism and the success and associated limitations of the YFV-17D vaccine. In addition, we highlight the current lack of available treatments and use publicly available sequence and structural data to assess global patterns of YFV sequence diversity and identify potential drug targets. Finally, we discuss how technological advances, including real-time epidemiological monitoring of outbreaks using next-generation sequencing and CRISPR/Cas9 modification of vector species, could be utilized in future battles against this re-emerging pathogen which continues to cause devastating disease.

• E protein structure
• animal models
• flavivirus entry factor
• global diversity
• host immune response
• re-emerging virus
• transmission and vector control
• vaccine
• yellow fever virus
• yellow fever virus tropism