ABSTRACT
This study presents a computational investigation of a stochastic Zika virus along with optimal control model using the Legendre spectral collocation method (LSCM). By accumulation of stochasticity into the model through the proposed stochastic differential equations, we appropriating the random fluctuations essential in the progression and disease transmission. The stability, convergence and accuracy properties of the LSCM are conscientiously analyzed and also demonstrating its strength for solving the complex epidemiological models. Moreover, the study evaluates the various control strategies, such as treatment, prevention and treatment pesticide control, and identifies optimal combinations that the intervention costs and also minimize the proposed infection rates. The basic properties of the given model, such as the reproduction number, were determined with and without the presence of the control strategies. For R 0 < 0 , the model satisfies the disease-free equilibrium, in this case the disease die out after some time, while for R 0 > 1 , then endemic equilibrium is satisfied, in this case the disease spread in the population at higher scale. The fundamental findings acknowledge the significant impact of stochastic phonemes on the robustness and effectiveness of control strategies that accelerating the need for cost-effective and multi-faceted approaches. In last the results provide the valuable insights for public health department to enabling more impressive mitigation of Zika virus outbreaks and management in real-world scenarios.
Subject(s)
Stochastic Processes , Zika Virus Infection , Zika Virus , Zika Virus Infection/epidemiology , Zika Virus Infection/prevention & control , Zika Virus Infection/transmission , Humans , Zika Virus/physiology , Computer Simulation , Epidemiological ModelsABSTRACT
Zika virus infection, most oft n responsible for a benign arboviral disease or an asymptomatic infection, rarely Guillain-Barré syndrome, can become problematic in pregnant women, due to a risk of fetal malformations, in particular microcephaly linked to its neurotropism. The most recent large-scale epidemic was observed throughout Latin America between 2015 and 2017, causing several hundred thousand cases. Transmission is predominantly vector-borne, but sexual transmission has been described, mainly among travelers, although it undoubtedly accounts for a significant proportion of transmission in epidemic areas. The aim of this review is to describe this sexual transmission, mainly through examples linked to this large-scale epidemic in Latin America, to describe the link with prolonged excretion of infectious viral particles in genital secretions, especially semen but also vaginal secretions, and to highlight possible preventive measures apart from vector transmission, in particular the need for pregnant women or women wishing to become pregnant to avoid visiting countries where circulation of Zika virus is described.
Subject(s)
Sexually Transmitted Diseases, Viral , Zika Virus Infection , Zika Virus Infection/transmission , Zika Virus Infection/prevention & control , Zika Virus Infection/epidemiology , Humans , Female , Pregnancy , Sexually Transmitted Diseases, Viral/transmission , Sexually Transmitted Diseases, Viral/prevention & control , Sexually Transmitted Diseases, Viral/epidemiology , Pregnancy Complications, Infectious/prevention & control , Pregnancy Complications, Infectious/virology , Pregnancy Complications, Infectious/epidemiology , Male , Latin America/epidemiologyABSTRACT
The Zika virus (ZIKV) is an emerging virus associated with the Flaviviridae family that mainly causes infection in pregnant women and leads to several abnormalities during pregnancy. This virus has unique properties that may lead to pathological diseases. As the virus has the ability to evade immune response, a crucial effort is required to deal with ZIKV. Vaccines are a safe means to control different pathogenic infectious diseases. In the current research, a multi-epitope-based vaccination against ZIKV is being designed using in silico methods. For the epitope prediction and prioritization phase, ZIKV polyprotein (YP_002790881.1) and flavivirus polyprotein (>YP_009428568.1) were targeted. The predicted B-cell epitopes were used for MHC-I and MHC-II epitope prediction. Afterward, several immunoinformatics filters were applied and nine (REDLWCGSL, MQDLWLLRR, YKKSGITEV, TYTDRRWCF, RDAFPDSNS, KPSLGLINR, ELIGRARVS, AITQGKREE, and EARRSRRAV) epitopes were found to be probably antigenic in nature, non-allergenic, non-toxic, and water soluble without any toxins. Selected epitopes were joined using a particular GPGPG linker to create the base vaccination for epitopes, and an extra EAAAK linker was used to link the adjuvant. A total of 312 amino acids with a molecular weight (MW) of 31.62762 and an instability value of 34.06 were computed in the physicochemical characteristic analysis, indicating that the vaccine design is stable. The molecular docking analysis predicted a binding energy of -329.46 (kcal/mol) for TLR-3 and -358.54 (kcal/mol) for TLR-2. Moreover, the molecular dynamics simulation analysis predicted that the vaccine and receptor molecules have stable binding interactions in a dynamic environment. The C-immune simulation analysis predicted that the vaccine has the ability to generate both humoral and cellular immune responses. Based on the design, the vaccine construct has the best efficacy to evoke immune response in theory, but experimental analysis is required to validate the in silico base approach and ensure its safety.
Subject(s)
Computational Biology , Epitopes, B-Lymphocyte , Viral Vaccines , Zika Virus Infection , Zika Virus , Zika Virus/immunology , Viral Vaccines/immunology , Zika Virus Infection/prevention & control , Zika Virus Infection/immunology , Humans , Epitopes, B-Lymphocyte/immunology , Computational Biology/methods , Vaccine Development , Molecular Docking Simulation , Epitopes, T-Lymphocyte/immunology , Epitopes, T-Lymphocyte/chemistry , Models, Molecular , ImmunoinformaticsABSTRACT
Congenital Zika syndrome (CZS) is a major concern in India and highlights the multifaceted challenges posed by the Zika virus (ZIKV). The alarming increase in CZS cases in India, a condition that has serious effects on both public health and newborns, has raised concerns. This review highlights the importance of raising concern and awareness and taking preventive measures by studying the epidemiology, clinical symptoms, and potential long-term consequences of CZS. The review also contributes to worldwide research and information sharing to improve the understanding and prevention of CZS. As India deals with the changing nature of CZS, this thorough review is an important tool for policymakers, health workers, and researchers to understand what is happening now, plan for what to do in the future, and work together as a team, using medical knowledge, community involvement, and study projects to protect newborns' health and reduce the public health impact of these syndromes.
Subject(s)
Pregnancy Complications, Infectious , Zika Virus Infection , Humans , Zika Virus Infection/epidemiology , Zika Virus Infection/congenital , Zika Virus Infection/prevention & control , Zika Virus Infection/complications , India/epidemiology , Pregnancy , Infant, Newborn , Pregnancy Complications, Infectious/epidemiology , Pregnancy Complications, Infectious/prevention & control , Female , Zika Virus , Microcephaly/epidemiology , Microcephaly/virology , Microcephaly/etiologyABSTRACT
The complete lack of yellow fever virus (YFV) in Asia, and the lack of urban YFV transmission in South America, despite the abundance of the peridomestic mosquito vector Aedes (Stegomyia.) aegypti is an enigma. An immunologically naïve population of over 2 billion resides in Asia, with most regions infested with the urban YF vector. One hypothesis for the lack of Asian YF, and absence of urban YF in the Americas for over 80 years, is that prior immunity to related flaviviruses like dengue (DENV) or Zika virus (ZIKV) modulates YFV infection and transmission dynamics. Here we utilized an interferon α/ß receptor knock-out mouse model to determine the role of pre-existing dengue-2 (DENV-2) and Zika virus (ZIKV) immunity in YF virus infection, and to determine mechanisms of cross-protection. We utilized African and Brazilian YF strains and found that DENV-2 and ZIKV immunity significantly suppresses YFV viremia in mice, but may or may not protect relative to disease outcomes. Cross-protection appears to be mediated mainly by humoral immune responses. These studies underscore the importance of re-assessing the risks associated with YF outbreak while accounting for prior immunity from flaviviruses that are endemic.
Subject(s)
Cross Protection , Dengue Virus , Disease Models, Animal , Mice, Knockout , Receptor, Interferon alpha-beta , Yellow Fever , Yellow fever virus , Zika Virus Infection , Zika Virus , Animals , Yellow Fever/immunology , Yellow Fever/prevention & control , Yellow Fever/virology , Mice , Cross Protection/immunology , Yellow fever virus/immunology , Zika Virus/immunology , Zika Virus Infection/immunology , Zika Virus Infection/prevention & control , Zika Virus Infection/virology , Dengue Virus/immunology , Receptor, Interferon alpha-beta/genetics , Receptor, Interferon alpha-beta/deficiency , Antibodies, Viral/immunology , Antibodies, Viral/blood , Flavivirus/immunology , Aedes/virology , Aedes/immunology , Dengue/immunology , Dengue/prevention & control , Dengue/virology , Female , Viremia/immunology , Mosquito Vectors/virology , Mosquito Vectors/immunology , Flavivirus Infections/immunology , Flavivirus Infections/prevention & control , Flavivirus Infections/virology , Mice, Inbred C57BLABSTRACT
Humans continue to be at risk from the Zika virus. Although there have been significant research advancements regarding Zika, the absence of a vaccine or approved treatment poses further challenges for healthcare providers. In this study, we developed a microparticulate Zika vaccine using an inactivated whole Zika virus as the antigen that can be administered pain-free via intranasal (IN) immunization. These microparticles (MP) were formulated using a double emulsion method developed by our lab. We explored a prime dose and two-booster-dose vaccination strategy using MPL-A® and Alhydrogel® as adjuvants to further stimulate the immune response. MPL-A® induces a Th1-mediated immune response and Alhydrogel® (alum) induces a Th2-mediated immune response. There was a high recovery yield of MPs, less than 5 µm in size, and particle charge of -19.42 ± 0.66 mV. IN immunization of Zika MP vaccine and the adjuvanted Zika MP vaccine showed a robust humoral response as indicated by several antibodies (IgA, IgM, and IgG) and several IgG subtypes (IgG1, IgG2a, and IgG3). Vaccine MP elicited a balance Th1- and Th2-mediated immune response. Immune organs, such as the spleen and lymph nodes, exhibited a significant increase in CD4+ helper and CD8+ cytotoxic T-cell cellular response in both vaccine groups. Zika MP vaccine and adjuvanted Zika MP vaccine displayed a robust memory response (CD27 and CD45R) in the spleen and lymph nodes. Adjuvanted vaccine-induced higher Zika-specific intracellular cytokines than the unadjuvanted vaccine. Our results suggest that more than one dose or multiple doses may be necessary to achieve necessary immunological responses. Compared to unvaccinated mice, the Zika vaccine MP and adjuvanted MP vaccine when administered via intranasal route demonstrated robust humoral, cellular, and memory responses. In this pre-clinical study, we established a pain-free microparticulate Zika vaccine that produced a significant immune response when administered intranasally.
Subject(s)
Administration, Intranasal , Antibodies, Viral , Viral Vaccines , Zika Virus Infection , Zika Virus , Animals , Zika Virus Infection/prevention & control , Zika Virus Infection/immunology , Zika Virus/immunology , Mice , Antibodies, Viral/blood , Antibodies, Viral/immunology , Viral Vaccines/immunology , Viral Vaccines/administration & dosage , Female , Immunization/methods , Adjuvants, Immunologic/administration & dosage , Disease Models, Animal , Adjuvants, Vaccine/administration & dosage , Vaccination/methods , Cytokines/immunology , Antibodies, Neutralizing/blood , Antibodies, Neutralizing/immunologyABSTRACT
Zika virus (ZIKV) is a mosquito-borne flavivirus that highly susceptibly causes Guillain-Barré syndrome and microcephaly in newborns. Vaccination is one of the most effective measures for preventing infectious diseases. However, there is currently no approved vaccine to prevent ZIKV infection. Here, we developed nanoparticle (NP) vaccines by covalently conjugating self-assembled 24-subunit ferritin to the envelope structural protein subunit of ZIKV to achieve antigen polyaggregation. The immunogenicityof the NP vaccine was evaluated in mice. Compared to monomer vaccines, the NP vaccine achieved effective antigen presentation, promoted the differentiation of follicular T helper cells in lymph nodes, and induced significantly greater antigen-specific humoral and cellular immune responses. Moreover, the NP vaccine enhanced high-affinity antigen-specific IgG antibody levels, increased secretion of the cytokines IL-4 and IFN-γ by splenocytes, significantly activated T/B lymphocytes, and improved the generation of memory T/B cells. In addition, no significant adverse reactions occurred when NP vaccine was combined with adjuvants. Overall, ferritin-based NP vaccines are safe and effective ZIKV vaccine candidates.
Subject(s)
Ferritins , Nanoparticles , Viral Vaccines , Zika Virus Infection , Zika Virus , Animals , Zika Virus/immunology , Zika Virus Infection/prevention & control , Zika Virus Infection/immunology , Viral Vaccines/immunology , Viral Vaccines/administration & dosage , Female , Mice , Ferritins/immunology , Immunogenicity, Vaccine , Antibodies, Viral/immunology , Antibodies, Viral/blood , Immunity, Cellular/drug effects , Immunoglobulin G/blood , Immunoglobulin G/immunology , Immunity, Humoral/drug effects , B-Lymphocytes/immunology , Mice, Inbred BALB C , Viral Envelope Proteins/immunology , Viral Envelope Proteins/administration & dosage , NanovaccinesABSTRACT
BACKGROUND: Dengue, Zika, and chikungunya, whose viruses are transmitted mainly by Aedes aegypti, significantly impact human health worldwide. Despite the recent development of promising vaccines against the dengue virus, controlling these arbovirus diseases still depends on mosquito surveillance and control. Nonetheless, several studies have shown that these measures are not sufficiently effective or ineffective. Identifying higher-risk areas in a municipality and directing control efforts towards them could improve it. One tool for this is the premise condition index (PCI); however, its measure requires visiting all buildings. We propose a novel approach capable of predicting the PCI based on facade street-level images, which we call PCINet. METHODOLOGY: Our study was conducted in Campinas, a one million-inhabitant city in São Paulo, Brazil. We surveyed 200 blocks, visited their buildings, and measured the three traditional PCI components (building and backyard conditions and shading), the facade conditions (taking pictures of them), and other characteristics. We trained a deep neural network with the pictures taken, creating a computational model that can predict buildings' conditions based on the view of their facades. We evaluated PCINet in a scenario emulating a real large-scale situation, where the model could be deployed to automatically monitor four regions of Campinas to identify risk areas. PRINCIPAL FINDINGS: PCINet produced reasonable results in differentiating the facade condition into three levels, and it is a scalable strategy to triage large areas. The entire process can be automated through data collection from facade data sources and inferences through PCINet. The facade conditions correlated highly with the building and backyard conditions and reasonably well with shading and backyard conditions. The use of street-level images and PCINet could help to optimize Ae. aegypti surveillance and control, reducing the number of in-person visits necessary to identify buildings, blocks, and neighborhoods at higher risk from mosquito and arbovirus diseases.
Subject(s)
Aedes , Dengue , Mosquito Vectors , Aedes/virology , Aedes/physiology , Animals , Brazil/epidemiology , Humans , Mosquito Vectors/virology , Mosquito Vectors/physiology , Dengue/prevention & control , Dengue/epidemiology , Dengue/transmission , Cities , Mosquito Control/methods , Image Processing, Computer-Assisted/methods , Zika Virus Infection/prevention & control , Zika Virus Infection/epidemiology , Zika Virus Infection/transmissionABSTRACT
Arboviral diseases remain a significant health concern worldwide, with over half the world's population at risk for dengue alone. Without a vaccine or targeted treatment, the most effective strategy of prevention is vector management with community involvement. mHealth interventions, like WhatsApp, offer promising results for engaging communities and promoting healthier behaviors. This study explores the feasibility of integrating WhatsApp in vector control activities to improve arbovirus prevention in Colombia. A mixed-methods approach was employed to assess the WhatsApp-based intervention. WhatsApp messages were sent to 45 community women for 5 weeks to increase their knowledge and practices about dengue, Zika, and chikungunya. Pre-and-post surveys and focus group discussions were conducted in community settings to measure the feasibility and acceptability of this intervention. Chat reviews were done to assess the usability of users. A total of 1566 messages were exchanged in 45 WhatsApp chats. High acceptance and good usability (82% of users used the app for replying) were reported in this study. WhatsApp messages were perceived as short, clear, and enjoyable. Users liked the frequency, and design of messages. Pre- and post-surveys demonstrated improvements in the knowledge and practices of arboviral diseases. The intention to apply this knowledge in practice was reflected in a significant improvement, particularly in cleaning the laundry tank once a week (pre 62.1% to post 89.6%, p < 0.008). This study suggests that using WhatsApp as an additional tool could be a feasible, acceptable, and affordable strategy for improving the adoption of better practices in the prevention of arboviral diseases.
Subject(s)
Arbovirus Infections , Feasibility Studies , Mobile Applications , Humans , Colombia/epidemiology , Female , Arbovirus Infections/prevention & control , Adult , Health Knowledge, Attitudes, Practice , Dengue/prevention & control , Zika Virus Infection/prevention & control , Chikungunya Fever/prevention & control , Chikungunya Fever/epidemiology , Telemedicine , Middle Aged , Young Adult , Surveys and QuestionnairesABSTRACT
The Zika virus (ZIKV) is considered a public health problem worldwide due to its association with the development of microcephaly and the Guillain-Barré syndrome. Currently, there is no specific treatment or vaccine approved to combat this disease, and thus, developing safe and effective vaccines is a relevant goal. In this study, a multi-epitope protein called rpZDIII was designed based on a series of ZIKV antigenic sequences, a bacterial carrier, and linkers. The analysis of the predicted 3D structure of the rpZDIII chimeric antigen was performed on the AlphaFold 2 server, and it was produced in E. coli and purified from inclusion bodies, followed by solubilization and refolding processes. The yield achieved for rpZDIII was 11 mg/L in terms of pure soluble recombinant protein per liter of fermentation. rpZDIII was deemed immunogenic since it induced serum IgG and IgM responses in mice upon subcutaneous immunization in a three-dose scheme. Moreover, sera from mice immunized with rpZDIII showed neutralizing activity against ZIKV. Therefore, this study reveals rpZDIII as a promising immunogen for the development of a rationally designed multi-epitope vaccine against ZIKV, and completion of its preclinical evaluation is guaranteed.
Subject(s)
Antibodies, Neutralizing , Antibodies, Viral , Antigens, Viral , Zika Virus Infection , Zika Virus , Animals , Zika Virus/immunology , Antibodies, Neutralizing/immunology , Antibodies, Neutralizing/blood , Mice , Antibodies, Viral/immunology , Antibodies, Viral/blood , Zika Virus Infection/prevention & control , Zika Virus Infection/immunology , Antigens, Viral/immunology , Antigens, Viral/genetics , Viral Vaccines/immunology , Viral Vaccines/administration & dosage , Epitopes/immunology , Immunoglobulin G/blood , Immunoglobulin G/immunology , Female , Escherichia coli/genetics , Escherichia coli/metabolism , Immunoglobulin M/immunology , Immunoglobulin M/blood , Mice, Inbred BALB CABSTRACT
Abstract: Timor-Leste is a mountainous, half-island nation with a population of 1.3 million, which shares a land border with Indonesia and is 550 km from Darwin, Australia. Since independence in 2002, Timor-Leste has achieved significant development; however, high levels of poverty remain. Chikungunya virus (CHIKV) is endemic in over 100 countries in Africa, Asia, Europe and in the Americas. It is transmitted by the bite of infected Aedes aegypti or Ae. albopictus mosquitoes, which are present in Timor-Leste and which contribute to annual rainy-season dengue virus (DENV) outbreaks. Symptomatic people typically suffer from acute onset of fever, usually accompanied by severe arthritis or arthralgia. Joint pain can be debilitating for several days, and may sometimes last for weeks, months or years. Unlike DENV infection which has significant mortality, most people recover completely. Between 2002 and 2023, there were 26 cases of CHIKV notified in Australia who acquired their infection in Timor-Leste; however, laboratory testing capability for CHIKV in Timor-Leste only became available in 2021 using polymerase chain reaction (PCR). The first locally diagnosed case was notified in November 2023. In January 2024, an outbreak of CHIKV was recognised in Timor-Leste for the first time, with 195 outbreak cases reported during 1-31 January 2024; all were PCR positive. There were no cases hospitalised, and no deaths. The median age of cases was 17 years (range 1-76 years); 51% were males. Cases were reported across the country; most (88/195) were from Dili, although the highest incidence was seen in the neighbouring municipality of Ermera (monthly incidence rate of 58.8 cases per 100,000 population). This first reported outbreak of CHIKV in Timor-Leste highlights the need for improved mosquito-borne illness control and response strategies, including minimising breeding sites and promoting early presentation for treatment and differential diagnosis from DENV, and consideration of the deployment of Wolbachia-infected mosquitoes, particularly as they have shown to reduce the transmission of CHIKV, DENV and Zika virus, all of which pose threats in Timor-Leste.
Subject(s)
Chikungunya Fever , Chikungunya virus , Zika Virus Infection , Zika Virus , Male , Animals , Humans , Infant , Child, Preschool , Child , Adolescent , Young Adult , Adult , Middle Aged , Aged , Female , Chikungunya Fever/epidemiology , Timor-Leste/epidemiology , Australia/epidemiology , Chikungunya virus/genetics , Disease Outbreaks , Zika Virus Infection/epidemiology , Zika Virus Infection/prevention & controlABSTRACT
Naturally occurring bacterium could offer an additional way to control mosquito-borne diseases.
Subject(s)
Aedes , Dengue Virus , Dengue , Enterobacteriaceae , Gastrointestinal Microbiome , Mosquito Vectors , Zika Virus Infection , Zika Virus , Animals , Humans , Aedes/microbiology , Dengue/prevention & control , Dengue/virology , Mosquito Vectors/microbiology , Zika Virus Infection/prevention & control , Zika Virus Infection/virologyABSTRACT
The Zika Contraception Access Network (Z-CAN) provided access to high-quality client-centered contraceptive services across Puerto Rico during the 2016-2017 Zika virus outbreak. We sent online surveys during May 2017-August 2020 to a subset of Z-CAN patients at 6, 24, and 36 months after program enrollment (response rates: 55-60 percent). We described contraceptive method continuation, method satisfaction, and method switching, and we identified characteristics associated with discontinuation using multivariable logistic regression. Across all contraceptive methods, continuation was 82.5 percent, 64.2 percent, and 49.9 percent at 6, 24, and 36 months, respectively. Among continuing users, method satisfaction was approximately ≥90 percent. Characteristics associated with decreased likelihood of discontinuation included: using an intrauterine device or implant compared with a nonlong-acting reversible contraceptive method (shot, pills, ring, patch, or condoms alone); wanting to prevent pregnancy at follow-up; and receiving as their baseline method the same method primarily used before Z-CAN. Other associated characteristics included: receiving the method they were most interested in postcounseling (6 and 24 months) and being very satisfied with Z-CAN services at the initial visit (6 months). Among those wanting to prevent pregnancy at follow-up, about half reported switching to another method. Ongoing access to contraceptive services is essential for promoting reproductive autonomy, including supporting patients with continued use, method switching, or discontinuation.
Subject(s)
Zika Virus Infection , Humans , Puerto Rico/epidemiology , Female , Zika Virus Infection/epidemiology , Zika Virus Infection/prevention & control , Adult , Young Adult , Adolescent , Contraception/statistics & numerical data , Health Services Accessibility/statistics & numerical data , Contraception Behavior/statistics & numerical data , Family Planning Services/organization & administrationABSTRACT
Arboviruses represent a threat to transfusion safety for several reasons: the presence of vectors and the notification of autochthonous cases in our region, the recent increase in the number of cases transmitted through blood and/or blood component transfusion, the high prevalence rates of RNA of the main arboviruses in asymptomatic blood donors, and their ability to survive processing and storage in the different blood components. In an epidemic outbreak caused by an arbovirus in our region, transfusion centres can apply different measures: reactive measures, related to donor selection or arbovirus screening, and proactive measures, such as pathogen inactivation methods. The study of the epidemiology of the main arboviruses and understanding the effectiveness of the different measures that we can adopt are essential to ensure that our blood components remain safe.
Subject(s)
Arbovirus Infections , Arboviruses , Blood Donors , Blood Safety , Transfusion Reaction , Humans , Spain/epidemiology , Arbovirus Infections/transmission , Arbovirus Infections/epidemiology , Arbovirus Infections/prevention & control , Transfusion Reaction/epidemiology , Donor Selection/standards , Disease Outbreaks/prevention & control , Blood Transfusion/standards , Zika Virus Infection/transmission , Zika Virus Infection/epidemiology , Zika Virus Infection/prevention & control , West Nile Fever/transmission , West Nile Fever/epidemiology , West Nile Fever/prevention & control , West Nile Fever/diagnosisABSTRACT
Zika virus (ZIKV) and Japanese encephalitis virus (JEV) are antigenically related flaviviruses that co-circulate in many countries/territories. The interaction between the two viruses needs to be determined. Recent findings by ourselves and other labs showed that JEV-elicited antibodies (Abs) and CD8+T cells exacerbate and protect against subsequent ZIKV infection, respectively. However, the impact of JEV envelope (E) protein domain III (EDIII)-induced immune responses on ZIKV infection is unclear. We show here that sera from JEV-EDIII-vaccinated mice cross-react with ZIKV-EDIII in vitro, and transfer of the same sera to mice significantly decreases death upon lethal ZIKV infection at a dose-dependent manner. Maternally acquired anti-JEV-EDIII Abs also significantly reduce the mortality of neonatal mice born to JEV-EDIII-immune mothers post ZIKV challenge. Similarly, transfer of ZIKV-EDIII-reactive IgG purified from JEV-vaccinated humans increases the survival of ZIKV-infected mice. Notably, transfer of an extremely low volume of JEV-EDIII-immune sera or ZIKV-EDIII-reactive IgG does not mediate the Ab-mediated enhancement (ADE) of ZIKV infection. Similarly, transfer of JEV-EDIII-elicited CD8+T cells protects recipient mice against ZIKV challenge. These results demonstrate that JEV-EDIII-induced immune components including Abs and T cells have protective roles in ZIKV infection, suggesting EDIII is a promising immunogen for developing effective and safety JEV vaccine.
Subject(s)
Antibodies, Viral , CD8-Positive T-Lymphocytes , Cross Protection , Encephalitis Virus, Japanese , Viral Envelope Proteins , Zika Virus Infection , Zika Virus , Animals , Zika Virus Infection/prevention & control , Zika Virus Infection/immunology , CD8-Positive T-Lymphocytes/immunology , Zika Virus/immunology , Antibodies, Viral/immunology , Antibodies, Viral/blood , Viral Envelope Proteins/immunology , Mice , Encephalitis Virus, Japanese/immunology , Cross Protection/immunology , Female , Cross Reactions , Encephalitis, Japanese/prevention & control , Encephalitis, Japanese/immunology , Humans , Immunoglobulin G/immunology , Immunoglobulin G/blood , Disease Models, Animal , ImmunizationSubject(s)
Aedes , Disease Outbreaks , Wastewater , Wolbachia , Zika Virus Infection , Zika Virus , Zika Virus Infection/epidemiology , Zika Virus Infection/prevention & control , Humans , Disease Outbreaks/prevention & control , Aedes/virology , Aedes/microbiology , Wastewater/microbiology , Wastewater/virology , Animals , Tropical Climate , Mosquito Vectors/virology , Mosquito Vectors/microbiologyABSTRACT
We report on the first case of congenital Zika syndrome to be identified during the COVID-19 pandemic in Puerto Rico. The Zika virus (ZIKV) infection was first seen in Puerto Rico in December 2015. It is a flavivirus with vertical transmission, spreading from infected mothers to their fetuses and having a broad spectrum of clinical manifestations, of which microcephaly is the most worrisome. In Puerto Rico, routine ZIKV screening during pregnancy was implemented in October 2016. However, this practice has become less frequent over time. Nevertheless, the transmission of ZIKV continues, so it is important to ensure routine ZIKV screening in endemic regions, such as Puerto Rico.
Subject(s)
COVID-19 , Zika Virus Infection , Zika Virus , Pregnancy , Infant , Female , Humans , Infant, Newborn , Zika Virus Infection/diagnosis , Zika Virus Infection/epidemiology , Zika Virus Infection/prevention & control , Pandemics , COVID-19/epidemiology , Infant, Premature , COVID-19 TestingABSTRACT
OBJECTIVES: Arboviruses, such as dengue (DENV), zika (ZIKV), and chikungunya (CHIKV), constitute a growing urban public health threat. Focusing on Aedes aegypti mosquitoes, their primary vectors, is crucial for mitigation. While traditional immature-stage mosquito surveillance has limitations, capturing adult mosquitoes through traps yields more accurate data on disease transmission. However, deploying traps presents logistical and financial challenges, demonstrating effective temporal predictions but lacking spatial accuracy. Our goal is to identify smaller representative areas within cities to enhance the early warning system for DENV outbreaks. METHODS: We created Sentinel Geographic Units (SGUs), smaller areas of 1 km2 within each stratum, larger areas, with the aim of aligning the Trap Positivity Index (TPI) and Adult Density Index (ADI) with their respective strata. We conducted a two-step evaluation of SGUs. First, we examined the equivalence of TPI and ADI between SGUs and strata from January 2017 to July 2022. Second, we assessed the ability of SGU's TPI and ADI to predict DENV outbreaks in comparison to Foz do Iguaçu's Early-Warning System, which forecasts outbreaks up to 4 weeks ahead. Spatial and temporal analyses were carried out, including data interpolation and model selection based on Akaike information criteria (AIC). RESULTS: Entomological indicators produced in small SGUs can effectively replace larger sentinel areas to access dengue outbreaks. Based on historical data, the best predictive capability is achieved 2 weeks after infestation verification. Implementing the SGU strategy with more frequent sampling can provide more precise space-time estimates and enhance dengue control. CONCLUSIONS: The implementation of SGUs offers an efficient way to monitor mosquito populations, reducing the need for extensive resources. This approach has the potential to improve dengue transmission management and enhance the public health response in endemic cities.
Subject(s)
Aedes , Cities , Dengue , Mosquito Vectors , Animals , Aedes/virology , Brazil/epidemiology , Dengue/epidemiology , Dengue/transmission , Dengue/prevention & control , Humans , Disease Outbreaks/prevention & control , Zika Virus Infection/epidemiology , Zika Virus Infection/prevention & control , Zika Virus Infection/transmission , Mosquito Control/methodsABSTRACT
Zika virus (ZIKV) is an enveloped, single-stranded and positive-stranded RNA virus of the genus Flavivirus in the family Flaviviridae. ZIKV can cross the placental barrier and infect the fetus, causing microcephaly, congenital ZIKV syndrome, and even fetal death. ZIKV infection can also lead to testicular damage and male sterility. But no effective drugs and vaccines are available up to now. Previous studies have shown that the cathelicidin antimicrobial peptide LL-37 can protect against ZIKV infection. However, LL-37 is a secreted peptide, which can be easily degraded in vivo. We herein constructed exosome-loaded LL-37 (named LL-37-TM-exo and TM-LL-37-exo) using the transmembrane protein TM to load LL-37 onto the membrane of exosome. We found that exosome-loaded LL-37 could significantly inhibit ZIKV infection in vitro and in vivo, and LL-37-TM-exo had stronger antiviral activity than that of TM-LL-37-exo, which could significantly reduce ZIKV-induced testicular injury and sperm injury, and had broad-spectrum antiviral effect. Compared to free LL-37, exosome-loaded LL-37 showed a better serum stability, higher efficiency to cross the placental barrier, and stronger antiviral activity. The mechanism of exosome-loaded LL-37 against ZIKV infection was consistent with that of free LL-37, which could directly inactivate viral particles, reduce the susceptibility of host cells, and act on viral replication stage. Our study provides a novel strategy for the development of LL-37 against viral infection.
Subject(s)
Cathelicidins , Exosomes , Zika Virus Infection , Zika Virus , Female , Humans , Male , Pregnancy , Antiviral Agents/therapeutic use , Exosomes/metabolism , Placenta , Virus Replication , Zika Virus/drug effects , Zika Virus/physiology , Zika Virus Infection/prevention & control , Zika Virus Infection/virologyABSTRACT
BACKGROUND: Although Zika virus infection is rarely reported now, continuous prevention is needed to achieve sustained eradication. This study aimed to explore the knowledge gaps, risk perception and preventive measures against Zika virus infection (ZIKV) in pregnant women in Malaysia. METHODS: We conducted in-depth virtual interviews with pregnant women between February and April 2022. The interviews were recorded and transcribed, and data were analyzed by content analysis. RESULTS: The majority of the participants demonstrated a commendable level of awareness regarding the signs and symptoms associated with ZIKV infection. They also exhibited a clear understanding of preventive measures, particularly emphasizing the importance of avoiding mosquito bites to minimize the risk of ZIKV transmission. However, a noteworthy gap in knowledge surfaced as a subset of participants remained uninformed about the potential for sexual transmission of ZIKV, which could lead to congenital ZIKV in pregnant women. Even among women who were cognizant of ZIKV and its potential negative health outcomes, associated with the infection, many of them did not perceive themselves to be at risk, mainly because ZIKV infection is infrequently discussed or heard of, leading to a sense of infections' rarity. While the adoption of preventive measures such as mosquito bite prevention during pregnancy was a common practice, however, prevention of sexually transmitted infections (STIs) including mosquito-borne diseases such as Zika is low. A minority of women express concerns about the sensitivity surrounding discussions and prevention of STIs within the context of marriage. Most of the participants were supportive of the provision of awareness of ZIKV infection in women during pregnancy and the involvement of men, especially in initiatives aimed at preventing transmission through sexual contact. CONCLUSION: This study uncovered gaps in both knowledge and practices pertaining ZIKV infection among pregnant women in the aftermath of the ZIKV pandemic. The insights gleaned from our research are valuable for shaping future interventions geared towards preventing the resurgence or facilitating the sustainable eradication of ZIKV.