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Frontiers in Immunology 2022Obesity is a global health problem that affects 650 million people worldwide and leads to diverse changes in host immunity. Individuals with obesity experience an... (Review)
Review
Obesity is a global health problem that affects 650 million people worldwide and leads to diverse changes in host immunity. Individuals with obesity experience an increase in the size and the number of adipocytes, which function as an endocrine organ and release various adipocytokines such as leptin and adiponectin that exert wide ranging effects on other cells. In individuals with obesity, macrophages account for up to 40% of adipose tissue (AT) cells, three times more than in adipose tissue (10%) of healthy weight individuals and secrete several cytokines and chemokines such as interleukin (IL)-1β, chemokine C-C ligand (CCL)-2, IL-6, CCL5, and tumor necrosis factor (TNF)-α, leading to the development of inflammation. Overall, obesity-derived cytokines strongly affect immune responses and make patients with obesity more prone to severe symptoms than patients with a healthy weight. Several epidemiological studies reported a strong association between obesity and severe arthropod-borne virus (arbovirus) infections such as dengue virus (DENV), chikungunya virus (CHIKV), West Nile virus (WNV), and Sindbis virus (SINV). Recently, experimental investigations found that DENV, WNV, CHIKV and Mayaro virus (MAYV) infections cause worsened disease outcomes in infected diet induced obese (DIO) mice groups compared to infected healthy-weight animals. The mechanisms leading to higher susceptibility to severe infections in individuals with obesity remain unknown, though a better understanding of the causes will help scientists and clinicians develop host directed therapies to treat severe disease. In this review article, we summarize the effects of obesity on the host immune response in the context of arboviral infections. We have outlined that obesity makes the host more susceptible to infectious agents, likely by disrupting the functions of innate and adaptive immune cells. We have also discussed the immune response of DIO mouse models against some important arboviruses such as CHIKV, MAYV, DENV, and WNV. We can speculate that obesity-induced disruption of innate and adaptive immune cell function in arboviral infections ultimately affects the course of arboviral disease. Therefore, further studies are needed to explore the cellular and molecular aspects of immunity that are compromised in obesity during arboviral infections or vaccination, which will be helpful in developing specific therapeutic/prophylactic interventions to prevent immunopathology and disease progression in individuals with obesity.
Topics: Animals; Mice; Arbovirus Infections; Obesity; Mice, Obese; Chikungunya virus; West Nile virus; Immunity
PubMed: 36466818
DOI: 10.3389/fimmu.2022.968582 -
PLoS Neglected Tropical Diseases Mar 2018Nutrition is a key factor in host-pathogen defense. Malnutrition can increase both host susceptibility and severity of infection through a number of pathways, and... (Review)
Review
Nutrition is a key factor in host-pathogen defense. Malnutrition can increase both host susceptibility and severity of infection through a number of pathways, and infection itself can promote nutritional deterioration and further susceptibility. Nutritional status can also strongly influence response to vaccination or therapeutic pharmaceuticals. Arthropod-borne viruses (arboviruses) have a long history of infecting humans, resulting in regular pandemics as well as an increasing frequency of autochthonous transmission. Interestingly, aside from host-related factors, nutrition could also play a role in the competence of vectors required for transmission of these viruses. Nutritional status of the host and vector could even influence viral evolution itself. Therefore, it is vital to understand the role of nutrition in the arbovirus lifecycle. This Review will focus on nutritional factors that could influence susceptibility and severity of infection in the host, response to prophylactic and therapeutic strategies, vector competence, and viral evolution.
Topics: Animals; Arbovirus Infections; Arboviruses; Culicidae; Host-Pathogen Interactions; Humans; Insect Vectors; Nutritional Status
PubMed: 29596427
DOI: 10.1371/journal.pntd.0006247 -
Current Opinion in Insect Science Aug 2018Experimental infections of insects with arboviruses are performed to achieve a variety of objectives but principally to draw inferences about the potential role of field... (Review)
Review
Experimental infections of insects with arboviruses are performed to achieve a variety of objectives but principally to draw inferences about the potential role of field populations in transmission or to explore the molecular basis of vector-pathogen interactions. The design of such studies determines both their reproducibility and the extent to which their results can be extrapolated to natural environments, and is constrained by the resources available. We discuss recent findings regarding the effects of nutrition, the microbiome, co-infecting agents and feeding methods on the outcome of such experiments, and identify resource-efficient ways to increase their relevance and reproducibility, including the development of community standards for reporting such studies and better standards for cell line and colony authentication.
Topics: Animals; Arbovirus Infections; Arboviruses; Host-Pathogen Interactions; Insect Vectors; Insecta; Reproducibility of Results
PubMed: 30551760
DOI: 10.1016/j.cois.2018.05.007 -
Viruses Jul 2015Arthropod-borne viruses (arboviruses) circulate in nature between arthropod vectors and vertebrate hosts. Arboviruses often cause devastating diseases in vertebrate... (Review)
Review
Arthropod-borne viruses (arboviruses) circulate in nature between arthropod vectors and vertebrate hosts. Arboviruses often cause devastating diseases in vertebrate hosts, but they typically do not cause significant pathology in their arthropod vectors. Following oral acquisition of a viremic bloodmeal from a vertebrate host, the arbovirus disease cycle requires replication in the cellular environment of the arthropod vector. Once the vector has become systemically and persistently infected, the vector is able to transmit the virus to an uninfected vertebrate host. In order to systemically infect the vector, the virus must cope with innate immune responses and overcome several tissue barriers associated with the midgut and the salivary glands. In this review we describe, in detail, the typical arbovirus infection route in competent mosquito vectors. Based on what is known from the literature, we explain the nature of the tissue barriers that arboviruses are confronted with in a mosquito vector and how arboviruses might surmount these barriers. We also point out controversial findings to highlight particular areas that are not well understood and require further research efforts.
Topics: Animals; Arbovirus Infections; Arboviruses; Culicidae; Humans; Insect Vectors; Salivary Glands
PubMed: 26184281
DOI: 10.3390/v7072795 -
Saudi Journal of Kidney Diseases and... 2017
Review
Topics: Arbovirus Infections; Arboviruses; Host-Pathogen Interactions; Humans; Kidney; Prognosis; Renal Insufficiency; Risk Factors
PubMed: 28937090
DOI: 10.4103/1319-2442.215124 -
Journal of Medical Virology Dec 2020Kawasaki disease (KD) is an inflammatory disease primarily affecting infants and young children, whose etiology remains uncertain. Observational studies of the overlap... (Review)
Review
Kawasaki disease (KD) is an inflammatory disease primarily affecting infants and young children, whose etiology remains uncertain. Observational studies of the overlap between KD outbreaks and seasonal peaks of arboviral infections, suggest the possible role of these pathogens as triggers of KD. In Venezuela, regions with the highest reported arboviral infections simultaneously have the highest incidence of KD. One proposed explanation for this association involves the role of proinflammatory mediators, interleukin-1 (IL-1), IL-6, tumor necrosis factor, and vascular endothelial growth factor as mediators of coronary endothelial damage. The promotion of inflammation and tissue destruction by these cytokines is thought to contribute to the coronary endothelial damage experienced in KD. The utilization of overlapping KD and arboviral infection trends contribute to the comprehension of KD etiology, with improvements in diagnosis, prognosis and treatment.
Topics: Humans; Mucocutaneous Lymph Node Syndrome; Venezuela; Seasons; Arbovirus Infections; Incidence; Infant; Child, Preschool; Cytokines; Disease Outbreaks
PubMed: 32740967
DOI: 10.1002/jmv.26381 -
Developmental and Comparative Immunology Mar 2020Here we have investigated whether bacterial challenges to larval stages of Aedes aegypti can influence the adults' immune and vector competence for dengue and Zika... (Review)
Review
Here we have investigated whether bacterial challenges to larval stages of Aedes aegypti can influence the adults' immune and vector competence for dengue and Zika viruses. We show that larval exposure to live Bacillus thuringiensis Berliner and Enterobacter ludwigii can result in the modulation of virus infection at the adult stage in the absence of bacterial carry-over between the two developmental stages. We observed a significant reduction in virus infection intensity in the mosquitoes exposed to bacteria as larvae but not re-exposed as adults. The pattern of immune gene transcript regulation after bacterial exposure varied between adults, depending on whether or not they had been exposed to bacteria as larvae. Adults exposed to bacteria as larvae showed an earlier immune gene mRNA enrichment when re-exposed as adults than did adults not exposed as larvae. Bacterial exposure of larvae appears to have only modest effects on adult fitness.
Topics: Aedes; Animals; Arbovirus Infections; Arboviruses; Bacillus thuringiensis; Disease Vectors; Enterobacter; Enterobacteriaceae Infections; Environmental Exposure; Gene Expression Regulation; Gram-Positive Bacterial Infections; Immunity, Innate; Larva; Life Cycle Stages; Mosquito Vectors
PubMed: 31726064
DOI: 10.1016/j.dci.2019.103540 -
Current Opinion in Pediatrics Apr 2023Dengue, chikungunya and zika have caused significant epidemics in the Caribbean in recent years. This review highlights their impact in Caribbean children. (Review)
Review
PURPOSE OF REVIEW
Dengue, chikungunya and zika have caused significant epidemics in the Caribbean in recent years. This review highlights their impact in Caribbean children.
RECENT FINDINGS
Dengue has been increasingly intense and severe, seroprevalence is 80-100% in the Caribbean, children have increased attributable morbidity and mortality. Severe dengue, especially dengue with haemorrhage was significantly associated with haemoglobin SC disease and multiple organ-systems involved. These included the gastrointestinal and haematologic systems with extremely high lactate dehydrogenases and creatinine phosphokinases and severely abnormal bleeding indices. Despite appropriate interventions, mortality was highest within the first 48 h of admission. Chikungunya, a togavirus, affected 80% of some Caribbean populations. Paediatric presentations included high fever, skin, joint and neurological manifestations. Children less than 5 years of age had the highest morbidity and mortality. This maiden chikungunya epidemic was explosive and overwhelmed public health systems. Zika, another flavivirus, has a seroprevalence of 15% in pregnancy, so the Caribbean remains susceptible. Paediatric complications include pregnancy losses, stillbirths, Congenital Zika syndrome, Guillain-Barre syndrome, acute disseminated encephalomyelitis and transverse myelitis. Neurodevelopment stimulation programs for zika-exposed infants have been effective in improving language and positive behaviour scores.
SUMMARY
Caribbean children remain at risk for dengue, chikungunya and zika, with high attributable morbidity and mortality.
Topics: Child; Humans; Zika Virus Infection; Chikungunya Fever; Dengue; Seroepidemiologic Studies; Arbovirus Infections; Zika Virus; Caribbean Region
PubMed: 36801979
DOI: 10.1097/MOP.0000000000001229 -
Current Opinion in Virology Dec 2015Arthropod-borne (arbo) viruses infect hematophagous arthropods (vectors) to maintain virus transmission between vertebrate hosts. The mosquito vector actively controls... (Review)
Review
Arthropod-borne (arbo) viruses infect hematophagous arthropods (vectors) to maintain virus transmission between vertebrate hosts. The mosquito vector actively controls arbovirus infection to minimize its fitness costs. The RNA interference (RNAi) pathway is the major antiviral response vectors use to restrict arbovirus infections. We know this because depleting RNAi gene products profoundly impacts arbovirus replication, the antiviral RNAi pathway genes undergo positive, diversifying selection and arboviruses have evolved strategies to evade the vector's RNAi responses. The vector's RNAi defense and arbovirus countermeasures lead to an arms race that prevents potential virus-induced fitness costs yet maintains arbovirus infections needed for transmission. This review will discuss the latest findings in RNAi-arbovirus interactions in the model insect (Drosophila melanogaster) and in specific mosquito vectors.
Topics: Animals; Arbovirus Infections; Arboviruses; Arthropod Vectors; Culicidae; DNA, Viral; Host-Pathogen Interactions; Immunity, Innate; Models, Animal; RNA Interference; RNA, Small Interfering; RNA, Viral; Virus Replication
PubMed: 26629932
DOI: 10.1016/j.coviro.2015.10.001 -
PLoS Neglected Tropical Diseases Jan 2021Arbovirus infection in Aedes aegypti has historically been quantified from a sample of the adult population by pooling collected mosquitoes to increase detectability....
Arbovirus infection in Aedes aegypti has historically been quantified from a sample of the adult population by pooling collected mosquitoes to increase detectability. However, there is a significant knowledge gap about the magnitude of natural arbovirus infection within areas of active transmission, as well as the sensitivity of detection of such an approach. We used indoor Ae. aegypti sequential sampling with Prokopack aspirators to collect all mosquitoes inside 200 houses with suspected active ABV transmission from the city of Mérida, Mexico, and tested all collected specimens by RT-PCR to quantify: a) the absolute arbovirus infection rate in individually tested Ae. aegypti females; b) the sensitivity of using Prokopack aspirators in detecting ABV-infected mosquitoes; and c) the sensitivity of entomological inoculation rate (EIR) and vectorial capacity (VC), two measures ABV transmission potential, to different estimates of indoor Ae. aegypti abundance. The total number of Ae. aegypti (total catch, the sum of all Ae. aegypti across all collection intervals) as well as the number on the first 10-min of collection (sample, equivalent to a routine adult aspiration session) were calculated. We individually tested by RT-PCR 2,161 Aedes aegypti females and found that 7.7% of them were positive to any ABV. Most infections were CHIKV (77.7%), followed by DENV (11.4%) and ZIKV (9.0%). The distribution of infected Aedes aegypti was overdispersed; 33% houses contributed 81% of the infected mosquitoes. A significant association between ABV infection and Ae. aegypti total catch indoors was found (binomial GLMM, Odds Ratio > 1). A 10-min indoor Prokopack collection led to a low sensitivity of detecting ABV infection (16.3% for detecting infected mosquitoes and 23.4% for detecting infected houses). When averaged across all infested houses, mean EIR ranged between 0.04 and 0.06 infective bites per person per day, and mean VC was 0.6 infectious vectors generated from a population feeding on a single infected host per house/day. Both measures were significantly and positively associated with Ae. aegypti total catch indoors. Our findings provide evidence that the accurate estimation and quantification of arbovirus infection rate and transmission risk is a function of the sampling effort, the local abundance of Aedes aegypti and the intensity of arbovirus circulation.
Topics: Aedes; Animals; Arbovirus Infections; Female; Male; Mosquito Vectors; Population Density
PubMed: 33395435
DOI: 10.1371/journal.pntd.0008972