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Biomedica : Revista Del Instituto... Dec 2023Aedes 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...
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 with abundant vegetation. The mosquitoes were transported to the Laboratorio de Investigaciones en Parasitología Tropical at the Universidad del Tolima for taxonomic determination.
RESULTS
We identified 708 A. albopictus specimens distributed throughout Ibague’s 13 communes. The highest vector abundance occurred in communes 10, 11, 7, 8, 2, and 9; communes 3, 4, 5, 6, 12, and 13 had a relative abundance of around 3%, while commune 1 had 2% of relative abundance.
CONCLUSIONS
Aedes albopictus is distributed throughout all the communes of Ibague. Its dispersion has probably been favored by this region’s environmental and social conditions. We recommend annual monitoring of these vectors populations and molecular characterization of the found arboviruses. Ascertaining this mosquito’s distribution throughout the city will enable focusing entomological control strategies and preventing future arbovirus outbreaks.
Topics: Animals; Mosquito Vectors; Aedes; Chikungunya Fever; Colombia; Zika Virus; Zika Virus Infection
PubMed: 38109139
DOI: 10.7705/biomedica.7010 -
Nature Communications Feb 2024The first step in disease pathogenesis for arboviruses is the establishment of infection following vector transmission. For La Crosse virus (LACV), the leading cause of...
The first step in disease pathogenesis for arboviruses is the establishment of infection following vector transmission. For La Crosse virus (LACV), the leading cause of pediatric arboviral encephalitis in North America, and other orthobunyaviruses, the initial course of infection in the skin is not well understood. Using an intradermal (ID) model of LACV infection in mice, we find that the virus infects and replicates nearly exclusively within skin-associated muscle cells of the panniculus carnosus (PC) and not in epidermal or dermal cells like most other arbovirus families. LACV is widely myotropic, infecting distal muscle cells of the peritoneum and heart, with limited infection of draining lymph nodes. Surprisingly, muscle cells are resistant to virus-induced cell death, with long term low levels of virus release progressing through the Golgi apparatus. Thus, skin muscle may be a key cell type for the initial infection and spread of arboviral orthobunyaviruses.
Topics: Humans; Child; Animals; Mice; Orthobunyavirus; Encephalitis, California; Arboviruses; La Crosse virus; Bunyaviridae Infections; Virus Replication; Muscles
PubMed: 38321047
DOI: 10.1038/s41467-024-45304-0 -
Journal of Clinical Microbiology Dec 2023Eastern equine encephalitis virus (EEEV), Madariaga virus (MADV), and Venezuelan equine encephalitis virus complex (VEEV) are New World alphaviruses transmitted by...
Real-time RT-PCR for Venezuelan equine encephalitis complex, Madariaga, and Eastern equine encephalitis viruses: application in human and mosquito public health surveillance in Panama.
Eastern equine encephalitis virus (EEEV), Madariaga virus (MADV), and Venezuelan equine encephalitis virus complex (VEEV) are New World alphaviruses transmitted by mosquitoes. They cause febrile and sometimes severe neurological diseases in human and equine hosts. Detecting them during the acute phase is hindered by non-specific symptoms and limited diagnostic tools. We designed and clinically assessed real-time reverse transcription polymerase chain reaction assays (rRT-PCRs) for VEEV complex, MADV, and EEEV using whole-genome sequences. Validation involved 15 retrospective serum samples from 2015 to 2017 outbreaks, 150 mosquito pools from 2015, and 118 prospective samples from 2021 to 2022 surveillance in Panama. The rRT-PCRs detected VEEV complex RNA in 10 samples (66.7%) from outbreaks, with one having both VEEV complex and MADV RNAs. VEEV complex RNA was found in five suspected dengue cases from disease surveillance. The rRT-PCR assays identified VEEV complex RNA in three () pools, leading to VEEV isolates in two. Phylogenetic analysis revealed the VEEV ID subtype in positive samples. Notably, 11.9% of dengue-like disease patients showed VEEV infections. Together, our rRT-PCR validation in human and mosquito samples suggests that this method can be incorporated into mosquito and human encephalitic alphavirus surveillance programs in endemic regions.
Topics: Humans; Animals; Horses; Encephalitis Virus, Eastern Equine; Encephalomyelitis, Venezuelan Equine; Culicidae; Reverse Transcriptase Polymerase Chain Reaction; Phylogeny; Encephalomyelitis, Eastern Equine; Prospective Studies; Public Health Surveillance; Retrospective Studies; Alphavirus; RNA; Dengue
PubMed: 37982611
DOI: 10.1128/jcm.00152-23 -
Trends in Parasitology Apr 2024Parasites can manipulate host behavior to enhance transmission, but our understanding of arbovirus-induced changes in mosquito behavior is limited. Here, we explore... (Review)
Review
Parasites can manipulate host behavior to enhance transmission, but our understanding of arbovirus-induced changes in mosquito behavior is limited. Here, we explore current knowledge on such behavioral alterations in mosquito vectors, focusing on host-seeking and blood-feeding behaviors. Reviewing studies on dengue, Zika, La Crosse, Sindbis, and West Nile viruses in Aedes or Culex mosquitoes reveals subtle yet potentially significant effects. However, assay heterogeneity and limited sample sizes challenge definitive conclusions. To enhance robustness, we propose using deep-learning tools for automated behavior quantification and stress the need for standardized assays. Additionally, conducting longitudinal studies across the extrinsic incubation period and integrating diverse traits into modeling frameworks are crucial for understanding the nuanced implications of arbovirus-induced behavioral changes for virus transmission dynamics.
Topics: Animals; Arboviruses; Zika Virus; Zika Virus Infection; Aedes; Mosquito Vectors
PubMed: 38423938
DOI: 10.1016/j.pt.2024.02.004 -
Communications Biology Nov 2023Diet-induced nutritional stress can influence pathogen transmission potential in mosquitoes by impacting life history traits, infection susceptibility, and immunity. To...
Diet-induced nutritional stress can influence pathogen transmission potential in mosquitoes by impacting life history traits, infection susceptibility, and immunity. To investigate these effects, we manipulate mosquito diets at larval and adult stages, creating two nutritional levels (low and normal), and expose adults to dengue virus (DENV). We observe that egg number is reduced by nutritional stress at both stages and viral exposure separately and jointly, while the likelihood of laying eggs is exclusively influenced by adult nutritional stress. Adult nutritional stress alone shortens survival, while any pairwise combination between both-stage stress and viral exposure have a synergistic effect. Additionally, adult nutritional stress increases susceptibility to DENV infection, while larval nutritional stress likely has a similar effect operating via smaller body size. Furthermore, adult nutritional stress negatively impacts viral titers in infected mosquitoes; however, some survive and show increased titers over time. The immune response to DENV infection is overall suppressed by larval and adult nutritional stress, with specific genes related to Toll, JAK-STAT, and Imd immune signaling pathways, and antimicrobial peptides being downregulated. Our findings underscore the importance of nutritional stress in shaping mosquito traits, infection outcomes, and immune responses, all of which impact the vectorial capacity for DENV transmission.
Topics: Animals; Dengue Virus; Dengue; Aedes; Larva; Antimicrobial Peptides
PubMed: 37932414
DOI: 10.1038/s42003-023-05516-4 -
MMWR. Morbidity and Mortality Weekly... Aug 2023Arthropod-borne viruses (arboviruses) are transmitted to humans primarily through the bites of infected mosquitoes or ticks, and in the continental United States, West...
Arthropod-borne viruses (arboviruses) are transmitted to humans primarily through the bites of infected mosquitoes or ticks, and in the continental United States, West Nile virus (WNV) is the leading cause of domestically acquired arboviral disease. Other arboviruses cause sporadic cases of disease as well as occasional outbreaks. This report summarizes 2021 surveillance data reported to CDC by U.S. jurisdictions for nationally notifiable arboviruses; the report excludes chikungunya, dengue, yellow fever, and Zika virus disease cases, because these infections were acquired primarily through travel during 2021. Forty-nine states and the District of Columbia reported 3,035 cases of domestic arboviral disease, including those caused by West Nile (2,911), La Crosse (40), Jamestown Canyon (32), Powassan (24), St. Louis encephalitis (17), unspecified California serogroup (six), and eastern equine encephalitis (five) viruses. Among the WNV disease cases, 2,008 (69%) were classified as neuroinvasive disease, for a national incidence of 0.61 cases per 100,000 population. Because arboviral diseases continue to cause serious illness, maintaining surveillance programs to monitor their transmission and prevalence is important to the direction and promotion of prevention activities. Health care providers should consider arboviral infections in the differential diagnosis of aseptic meningitis and encephalitis, obtain appropriate specimens for laboratory testing, and promptly report cases to public health authorities. Prevention depends on community and household efforts to reduce vector populations and personal protective measures to prevent mosquito and tick bites, such as use of Environmental Protection Agency-registered insect repellent and wearing protective clothing.
Topics: Horses; Animals; Humans; West Nile virus; Mosquito Vectors; Arbovirus Infections; Yellow Fever; District of Columbia; Zika Virus Infection; Culicidae; Zika Virus
PubMed: 37616182
DOI: 10.15585/mmwr.mm7234a1 -
Frontiers in Public Health 2023Murray Valley encephalitis virus (MVEV) is a mosquito-borne flavivirus known to cause infrequent yet substantial human outbreaks around the Murray Valley region of... (Review)
Review
INTRODUCTION
Murray Valley encephalitis virus (MVEV) is a mosquito-borne flavivirus known to cause infrequent yet substantial human outbreaks around the Murray Valley region of south-eastern Australia, resulting in significant mortality.
METHODS
The public health response to MVEV in Victoria in 2022-2023 included a climate informed pre-season risk assessment, and vector surveillance with mosquito trapping and laboratory testing for MVEV. Human cases were investigated to collect enhanced surveillance data, and human clinical samples were subject to serological and molecular testing algorithms to assess for co-circulating flaviviruses. Equine surveillance was carried out via enhanced investigation of cases of encephalitic illness. Integrated mosquito management and active health promotion were implemented throughout the season and in response to surveillance signals.
FINDINGS
Mosquito surveillance included a total of 3,186 individual trapping events between 1 July 2022 and 20 June 2023. MVEV was detected in mosquitoes on 48 occasions. From 2 January 2023 to 23 April 2023, 580 samples (sera and CSF) were tested for flaviviruses. Human surveillance detected 6 confirmed cases of MVEV infection and 2 cases of "flavivirus-unspecified." From 1 September 2022 to 30 May 2023, 88 horses with clinical signs consistent with flavivirus infection were tested, finding one probable and no confirmed cases of MVE.
DISCUSSION
The expanded, climate-informed vector surveillance system in Victoria detected MVEV in mosquitoes in advance of human cases, acting as an effective early warning system. This informed a one-health oriented public health response including enhanced human, vector and animal surveillance, integrated mosquito management, and health promotion.
Topics: Humans; Animals; Horses; Victoria; Encephalitis Virus, Murray Valley; Encephalitis, Arbovirus; Public Health; Seasons; Culicidae; Mosquito Vectors; Disease Outbreaks
PubMed: 37860808
DOI: 10.3389/fpubh.2023.1256149 -
PLoS Neglected Tropical Diseases Apr 2024Mosquito-borne arboviruses are expanding their territory and elevating their infection prevalence due to the rapid climate change, urbanization, and increased...
BACKGROUND
Mosquito-borne arboviruses are expanding their territory and elevating their infection prevalence due to the rapid climate change, urbanization, and increased international travel and global trade. Various significant arboviruses, including the dengue virus, Zika virus, Chikungunya virus, and yellow fever virus, are all reliant on the same primary vector, Aedes aegypti. Consequently, the occurrence of arbovirus coinfection in mosquitoes is anticipated. Arbovirus coinfection in mosquitoes has two patterns: simultaneous and sequential. Numerous studies have demonstrated that simultaneous coinfection of arboviruses in mosquitoes is unlikely to exert mutual developmental influence on these viruses. However, the viruses' interplay within a mosquito after the sequential coinfection seems intricated and not well understood.
METHODOLOGY/PRINCIPAL FINDINGS
We conducted experiments aimed at examining the phenomenon of arbovirus sequential coinfection in both mosquito cell line (C6/36) and A. aegypti, specifically focusing on dengue virus (DENV, serotype 2) and Zika virus (ZIKV). We firstly observed that DENV and ZIKV can sequentially infect mosquito C6/36 cell line, but the replication level of the subsequently infected ZIKV was significantly suppressed. Similarly, A. aegypti mosquitoes can be sequentially coinfected by these two arboviruses, regardless of the order of virus exposure. However, the replication, dissemination, and the transmission potential of the secondary virus were significantly inhibited. We preliminarily explored the underlying mechanisms, revealing that arbovirus-infected mosquitoes exhibited activated innate immunity, disrupted lipid metabolism, and enhanced RNAi pathway, leading to reduced susceptibility to the secondary arbovirus infections.
CONCLUSIONS/SIGNIFICANCE
Our findings suggest that, in contrast to simultaneous arbovirus coinfection in mosquitoes that can promote the transmission and co-circulation of these viruses, sequential coinfection appears to have limited influence on arbovirus transmission dynamics. However, it is important to note that more experimental investigations are needed to refine and expand upon this conclusion.
Topics: Animals; Zika Virus; Aedes; Zika Virus Infection; Dengue Virus; Coinfection; Mosquito Vectors; Arboviruses; Dengue
PubMed: 38557981
DOI: 10.1371/journal.pntd.0012053 -
Frontiers in Cellular and Infection... 2024
Topics: Humans; Hemorrhagic Fever Virus, Crimean-Congo; Hemorrhagic Fever, Crimean
PubMed: 38371295
DOI: 10.3389/fcimb.2024.1369530 -
PLoS Neglected Tropical Diseases Aug 2023After the unprecedented Zika virus (ZIKV) outbreak in the western hemisphere from 2015-2018, Aedes aegypti and Ae. albopictus are now well established primary and...
BACKGROUND
After the unprecedented Zika virus (ZIKV) outbreak in the western hemisphere from 2015-2018, Aedes aegypti and Ae. albopictus are now well established primary and secondary ZIKV vectors, respectively. Consensus about identification and importance of other secondary ZIKV vectors remain. This systematic review aims to provide a list of vector species capable of transmitting ZIKV by reviewing evidence from laboratory vector competence (VC) studies and to identify key knowledge gaps and issues within the ZIKV VC literature.
METHODS
A search was performed until 15th March 2022 on the Cochrane Library, Lilacs, PubMed, Web of Science, WHOLIS and Google Scholar. The search strings included three general categories: 1) "ZIKA"; 2) "vector"; 3) "competence", "transmission", "isolation", or "feeding behavior" and their combinations. Inclusion and exclusion criteria has been predefined and quality of included articles was assessed by STROBE and STROME-ID criteria.
FINDINGS
From 8,986 articles retrieved, 2,349 non-duplicates were screened by title and abstracts,103 evaluated using the full text, and 45 included in this analysis. Main findings are 1) secondary vectors of interest include Ae. japonicus, Ae. detritus, and Ae. vexans at higher temperature 2) Culex quinquefasciatus was not found to be a competent vector of ZIKV, 3) considerable heterogeneity in VC, depending on the local mosquito strain and virus used in testing was observed. Critical issues or gaps identified included 1) inconsistent definitions of VC parameters across the literature; 2) equivalency of using different mosquito body parts to evaluate VC parameters for infection (mosquito bodies versus midguts), dissemination (heads, legs or wings versus salivary glands), and transmission (detection or virus amplification in saliva, FTA cards, transmission to neonatal mice); 3) articles that fail to use infectious virus assays to confirm the presence of live virus; 4) need for more studies using murine models with immunocompromised mice to infect mosquitoes.
CONCLUSION
Recent, large collaborative multi-country projects to conduct large scale evaluations of specific mosquito species represent the most appropriate approach to establish VC of mosquito species.
Topics: Animals; Mice; Zika Virus; Zika Virus Infection; Mosquito Vectors; Aedes; Biological Assay
PubMed: 37651473
DOI: 10.1371/journal.pntd.0011591