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Nineteenth-Century British West Indies Soldiers Were Not Intrinsically Resistant to Disease Mortality in West Africa.

Expatriate soldiers often died at high rates because of infectious diseases when deployed into the tropics during the nineteenth century. A British regiment of Black soldiers from the West Indies was specifically raised to provide soldiers less likely to die of malaria and yellow fever than their White European counterparts. Black soldiers were initially recruited from recovered slaves born in West Africa, but recruitment was from free men born in the West Indies by the middle of the century. All-cause (ranging from 1% to 6%/year) and disease-specific annual mortality rates were collected from…

Preparation and evaluation of antisera for immunohistochemical detection of Zika virus in aldehyde-fixed tissues.

INTRODUCTION: The nervous system is one of the main targets of the Zika virus. It is essential to have biological reagents to use as diagnos … and tissues from experimentally infected animals. There was cross- immunoreactivity with dengue and yellow fever viruses but not with rabies virus. CONCLUSIONS: The utility of the two antiserums for the detection of Zika virus in samples of human origin and from experimental animals obtained by different histological techniques used for the investigation of Z …

The major component of Heteractis magnifica sea anemone venom, RpIII, exhibits strong subtype selectivity for insects over mammalian voltage-gated sodium channels.

Voltage-gated sodium channels (NaV) are molecular targets for the development of drugs for the treatment of diseases such as epilepsy, neuro … o insect channels. Cockroach (Blattella germanica) sodium channel BgNaV1 (EC50 of 2.4 ± 0.2 nM) and yellow fever mosquito (Aedes aegypti) channel AaNaV1 (EC50 of 1.5 ± 0.3 nM) were the most sensitive to RpIII, while mammals NaV had EC50 values above 100 nM except mNaV1.6 (EC50 of 43.8 ± 3.6 nM). The low nanomolar RpIII affinity to insect AaNaV1 may be explaine …

The Emerging Role of Circulating T Follicular Helper Cells in Dengue Virus Immunity: Balancing Protection and Pathogenesis.

Flaviviruses are a group of viruses transmitted mainly by mosquitoes and ticks, causing severe diseases in humans. Examples include dengue, Zika, West Nile virus, and yellow fever. They primarily affect individuals in tropical and subtropical regions, causing public health problems such as epidemic outbreaks and significant economic burdens due to hospitalizations and treatments. They share antigens, leading to cross-reactivity where antibodies generated against one flavivirus can react with others, complicating the accurate diagnosis of individual infections and making the development of trea…

Bioactivity of Linalool Against Culex quinquefasciatus: Repellent and Larvicidal Evaluations.

Mosquitoes spread a range of life-threatening illnesses such as malaria, dengue, zika virus, chikungunya, yellow fever, and many others, and cause up to 1 million deaths and 1 billion infections across the world every year. There has been growing interest in plant-based repellents that display bioactive compounds with insecticidal and repellent activities. In this review, the focus is on a natural monoterpene that has gained therapeutic properties, including antifungal, antibacterial, antioxidant, anticancer, and neuropharmacological activity, including anti-anxiety and sedative activity. The …

The effects of mating and blood feeding on the immune defense of female Aedes aegypti mosquitoes.

Mating and consequent reproduction have variable effects on the immune defenses of female insects, ranging from immune enhancement to immune suppression. Blood feeding, which is necessary to induce egg production in anautogenous insect species, also impacts immunity, with variable effects in different insect species. Because immunity is a key component of vector competence, and mating and blood feeding can influence immunity, we investigated the effects of these processes on immune defense in the yellow fever mosquito, Aedes aegypti. To explore both aspects of reproduction, we measured surviva…

Nanoparticles-mediated entomotoxicology: lessons from biologica.

Nanotechnology has grown in importance in medicine, manufacturing, and consumer products. Nanoparticles (NPs) are also widely used in the fi … the most published papers. The most overall reported models of insects were those of Aedes aegypti (yellow fever mosquito), Culex quinquefasciatus (southern house mosquito), Bombyx mori (silk moth), and Anopheles stephensi (Asian malaria mosquito). The application and methods of fabrication of NPs using insect tissues, as well as the mechanism of toxicity of N …

Genetic variability of Aedes aegypti (Diptera: Culicidae) in El Salvador and Honduras: presence of a widespread haplotype and implications for mosquito control.

BACKGROUND: This study examined population genetics of Aedes aegypti in El Salvador and Honduras, two adjacent countries in Central America. Aedes aegypti is associated with yellow fever, dengue, chikungunya, and Zika. Each year, thousands of cases of dengue are typically reported in El Salvador and Honduras. METHODS: In El Salvador, collections were obtained from five Departments. In Honduras, samples were obtained from six municipalities in four Departments. Mitochondrial DNA cytochrome oxidase I (COI) was sequenced, and consensus sequences were combined with available sequences from El Sal…

Improved methodology for fixation and preparation of Aedes aegypti embryos.

The yellow fever mosquito Aedes aegypti is a major disease vector and an increasingly popular emerging model research organism. We present here an improved protocol for the collection, fixation, and preparation of A. aegypti embryos for immunohistochemical and in situ hybridization studies. The processing of A. aegypti embryos for such studies is complicated by the inability to easily remove the vitelline membrane, which prevents the reagents needed for staining from reaching their targets, and which furthermore obscures visualization of the embryo since the membrane is highly sclerotized. Pre…

Single jar for collecting and rearing mosquito life stages: An innovative prototype.

BACKGROUND OBJECTIVES: Mosquitoes vectors are the key threat that spread viruses, bacteria, nematodes, protozoans, and other infections responsible for the transmission of serious public health ailments including dengue, yellow fever, malaria, and chikungunya. METHODS: To rear and cultivate mosquitoes at multiple stages of development (egg, larva, pupa, and adult) to be employed in various biomedical research, an innovative tool mosquito larva adult 2-in-1 rearing jar was designed and developed. The eggs/larvae or adults collected from the field or laboratory cultures can be released into the…

Parallel Multifactorial Process Optimization and Intensification for High-Yield Production of Live YF17D-Vectored Zika Vaccine.

The live-attenuated yellow fever 17D strain is a potent vaccine and viral vector. Its manufacture is based on embryonated chicken eggs or adherent Vero cells. Both processes are unsuitable for rapid and scalable supply. Here, we introduce a high-throughput workflow to identify suspension cells that are fit for the high-yield production of live YF17D-based vaccines in an intensified upstream process. The use of an automated parallel ambr15 microbioreactor system for screening and process optimization has led to the identification of two promising cell lines (AGE1.CR.pIX and HEKDyn) and the esta…

Factors Associated with Vaccination Adequacy in People Living with HIV: A Cross-Sectional Study.

People living with HIV (PLHIV) are at greater risk of illness and death from vaccine-preventable diseases. This study aimed to identify the predictors associated with the recommended vaccination schedule for this group. This was a single-center cross-sectional study conducted in a large Brazilian municipality, evaluating the vaccination statuses of 645 PLHIV for nine immunizers. The primary outcome was the adequacy of the vaccination schedule. The vaccination status was assessed for the diphtheria/tetanus, hepatitis B, hepatitis A, measles/mumps/rubella, yellow fever, 13- and 23-valent pneumoc…

Оценка времени, когда мыши питаются аэдесом аегипти, пробуют и кормят.

В комарах интрадермальный поиск крови позвоночного типа (время пробивания) соответствует времени, затраченному с момента первоначального ввода частей рта в кожу до визуализации первоначального образования крови в середине гортани. Оценка времени позволяет получить полезную информацию о способности комаров успешно питаться кровью. В этом протоколе мы описываем, как определить параметры питания в Aedes aegypti, широко распространенном комаре, который передает несколько смертоносных патогенов, включая желтую лихорадку, денге, Зика и вирусы Чикунгунья. Мы сосредоточимся на различных этапах процесс

Совпадение в аннотации оригинала
In mosquitoes, the intradermal search for vertebrate blood (probing time) corresponds to the time taken from initial insertion of the mouthp … in Aedes aegypti, a widely distributed mosquito that transmits several deadly pathogens, including yellow fever, dengue, Zika, and Chikungunya viruses. We focus on the different steps of a blood feeding event, including penetration, probing, interprobing, and feeding time. Penetration time corresponds to the insertion of the stylets into the host skin and usu …

Sugar restriction and blood ingestion shape divergent immune defense trajectories in the mosquito Aedes aegypti.

Immune defense is comprised of (1) resistance: the ability to reduce pathogen load, and (2) tolerance: the ability to limit the disease seve … concentration and blood ingestion on resistance and tolerance to Escherichia coli infection in the yellow fever mosquito Aedes aegypti. Resistance and tolerance were measured concurrently and at multiple timepoints. We found that mosquitoes from the restricted sugar treatment displayed enhanced resistance at all timepoints post-infection compared to those fro …

Fitness costs in the presence and absence of insecticide use explains abundance of two common Aedes aegypti kdr resistance alleles found in the Americas.

Aedes aegypti is the vector of viruses such as chikungunya, dengue, yellow fever and Zika that have a critical impact on human health. Control of adult mosquitoes is widely done using pyrethroids, but resistance has reduced the effectiveness of this class of insecticides. Resistance to pyrethroids in mosquitoes is commonly due to mutations in the voltage-gated sodium channel (Vgsc) gene (these mutations are known as knockdown resistance, kdr). In the Americas and the Caribbean, the most common kdr alleles are 410L+1016I+1534C and 1534C. In this study, we conducted a population cage experiment …

Aedes albopictus distribution in Ibagué, Colombia: Potential risk of arboviral outbreaks.

INTRODUCTION: Aedes albopictus is a vector for arboviruses, such as dengue, Zika, chikungunya, and yellow fever. The first A. albopictus reports on the American continent date back to 1985. It has spread rapidly throughout Colombia since its first report in 1998 due to its ecological and physiological adaptation capability. OBJECTIVE: To determine A. albopictus distribution in the 13 communes of Ibagué, Colombia. MATERIALS AND METHODS: Samples were collected between May and November 2022 in the 13 communes of Ibagué. Vacuum sampling and sweep-netting entomological nets were used in areas wit…

Indicators of the National Immunization Program for children under one year old: time trend in Maranhão, Brazil, 2010 to 2021.

We aimed to analyze the trend of indicators of the National Immunization Program (acronym in Portuguese. PNI) in children under one-year-old … e against Hepatitis B (p = 0.709) and oral human rotavirus (p = 0.143). The sharpest falls were for Yellow Fever (APC = 12.24%) and BCG (APC = 12.25%) vaccines. All VCH rates were lower than expected. with a drop from 2014 and APC between 5.75% (Pneumococcal 10; p = 0.033) and 14.02% (Poliomyelitis; p < 0.01). We observed an increasing trend in PA for Pentaval …

Elongation of N6-benzyladenosine scaffold via Pd-catalyzed C-C bond formation leads to derivatives with antiflaviviral activity.

Decoration of nucleoside analogues with lipophilic groups often leads to compounds with improved antiviral activity. For example, N6-benzyla … uents in the N6 position of adenosine on the antiviral activity against flaviviruses, such as TBEV, yellow fever virus (YFV) and West Nile virus (WNV), as well as a panel of enteroviruses including EV-A71, Echovirus 30 (E30), and poliovirus type 2 (PV2). Reproduction of tested flaviviruses appeared to be inhibited by the micromolar concentrations of the compou …

A Systematic Review of Vaccination Guidance for Humanitarian Responses.

Delivering vaccines in humanitarian response requires rigourous and continuous analysis of evidence. This systematic review mapped the norma … ns and limited rigour in guideline development. We found limited information on vaccines including, yellow fever, cholera, meningococcal, hepatitis A, and varicella, as well as human papilloma virus (HPV). There is a plethora of vaccination guidance for vaccine-preventable diseases in humanitarian contexts. However, gaps remain in the critical and systematic i …

Formulations of curcumin and d-mannitol as a photolarvicide against Aedes aegypti larvae: Sublethal photolarvicidal action, toxicity, residual evaluation, and small-scale field trial.

Dengue, Zika, chikungunya, and yellow fever are arboviruses transmitted by Aedes aegypti mosquito. In this regard, a number of techniques have emerged aiming to combat its proliferation. Elimination of Aedes aegypti larvae by photodynamic action has been reported as an efficient approach. In this regard, this study was aimed at synthetize and characterize formulations with different proportions (w/w) of the plant-based photolarvicidal curcumin and d-mannitol (CCD 1-4) and their evaluation on sublethal photolarvicidal efficiency, photodegradation profile,solubility, internalization, elimination…