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Insects Jun 2024The arbovirus West Nile virus (WNV) is a danger to global health. Spread primarily by mosquitoes, WNV causes about 2000 cases per year in the United States. The natural...
The arbovirus West Nile virus (WNV) is a danger to global health. Spread primarily by mosquitoes, WNV causes about 2000 cases per year in the United States. The natural mosquito immune response controls viral replication so that the host survives but can still transmit the virus. Using the genetically malleable model, we previously dissected innate immune pathways used to control WNV infection. Specifically, we showed that insulin/IGF-1 signaling (IIS) activates a JAK/STAT-mediated immune response that reduces WNV. However, how factors that regulate IIS in insects control infection has not been identified. () encodes a peptide hormone that suppresses insulin secretion. Its mammalian ortholog, Neuromedin U (NMU), is a peptide that regulates the production and secretion of insulin from pancreatic beta cells. In this study, we used and human cell culture models to investigate the roles of these insulin regulators in immune signaling. We found that mutants, which have elevated insulin-like peptide expression, are less susceptible to WNV infection. Increased levels of insulin-like peptides in these flies result in upregulated JAK/STAT activity, leading to protection from infection. Treatment of human cells with the insulin regulator NMU results in increased WNV replication. Further investigation of methods to target Lst in mosquitoes or NMU in mammals can improve vector control methods and may lead to improved therapeutics for human and animal infection.
PubMed: 38921161
DOI: 10.3390/insects15060446 -
Parasites & Vectors Jun 2024Past findings demonstrate that arthropods can egest midgut microbiota into the host skin leading to dual colonization of the vertebrate host with pathogens and saliva...
BACKGROUND
Past findings demonstrate that arthropods can egest midgut microbiota into the host skin leading to dual colonization of the vertebrate host with pathogens and saliva microbiome. A knowledge gap exists on how the saliva microbiome interacts with the pathogen in the saliva. To fill this gap, we need to first define the microbial composition of mosquito saliva.
METHODS
The current study aimed at analyzing and comparing the microbial profile of Aedes albopictus saliva and midgut as well as assessing the impact of Zika virus (ZIKV) infection on the midgut and saliva microbial composition. Colony-reared Ae. albopictus strains were either exposed to ZIKV infectious or noninfectious bloodmeal. At 14 ays postinfection, the 16S V3-V4 hypervariable rRNA region was amplified from midgut and saliva samples and sequenced on an Illumina MiSeq platform. The relative abundance and diversity of midgut and saliva microbial taxa were assessed.
RESULTS
We observed a richer microbial community in the saliva compared with the midgut, yet some of the microbial taxa were common in the midgut and saliva. ZIKV infection did not impact the microbial diversity of midgut or saliva. Further, we identified Elizabethkingia spp. in the Ae. albopictus saliva.
CONCLUSIONS
This study provides insights into the microbial community of the Ae. albopictus saliva as well as the influence of ZIKV infection on the microbial composition of its midgut and saliva. The identification of Elizabethkingia spp., an emerging pathogen of global health significance, in Ae. albopictus saliva is of medical importance. Future studies to assess the interactions between Ae. albopictus saliva microbiome and ZIKV could lead to novel strategies for developing transmission barrier tools.
Topics: Animals; Saliva; Aedes; Zika Virus; Mosquito Vectors; Microbiota; Gastrointestinal Microbiome; RNA, Ribosomal, 16S; Female; Zika Virus Infection; Gastrointestinal Tract
PubMed: 38918848
DOI: 10.1186/s13071-024-06334-1 -
PloS One 2024Dengue has emerged as an unprecedented epidemic in Peru, and it is anticipated that this issue will escalate further owing to climate change. This study aimed to...
BACKGROUND
Dengue has emerged as an unprecedented epidemic in Peru, and it is anticipated that this issue will escalate further owing to climate change. This study aimed to determine the risk factors associated with death from dengue in patients treated at Hospital II in Pucallpa, Peru.
METHODOLOGY
This retrospective cohort study collected information from the medical records of patients with a diagnosis of dengue treated at Hospital II Pucallpa-Peru between January 2019 and March 2023. The primary outcome was death, and the secondary outcome was death, development of severe dengue, or Intensive Care Unit (ICU) admission. Cox regression models were used to determine risk factors.
FINDINGS
The clinical records of 152 patients were evaluated, with a median age of 27.5 years (interquartile range, 11-45). Among all patients, 29 (19.1%) developed severe dengue, 31 (20.4%) were admitted to the ICU, and 13 (8.6%) died during follow-up. In the survival analysis, bilirubin >1.2 mg/dL was associated with a higher risk of death aHR: 11.38 (95% CI: 1.2 106.8). Additionally, factors associated with poor prognosis included having 1 to 3 comorbidities aRR: 1.92 (1.2 to 3.2), AST ≥251 U/L aRR: 6.79 (2.2 to 21.4), history of previous dengue aRR: 1.84 (1.0 to 3.3), and fibrinogen ≥400 mg/dL aRR: 2.23 (1.2 to 4.1).
SIGNIFICANCE
Elevated bilirubin was associated with death from dengue, whereas an increase in comorbidities and a history of previous dengue were related to a poor prognosis of the disease. Early identification of severe dengue would be more feasible with improved access to laboratory testing, particularly in tropical areas with a high dengue incidence.
Topics: Humans; Peru; Risk Factors; Male; Adult; Female; Middle Aged; Dengue; Retrospective Studies; Adolescent; Young Adult; Child; Intensive Care Units; Severe Dengue; Prognosis; Cohort Studies
PubMed: 38917093
DOI: 10.1371/journal.pone.0305689 -
Emerging Infectious Diseases Jul 2024We conducted a cross-sectional serosurvey for chikungunya virus (CHIKV) exposure in fruit bats in Senegal during 2020-2023. We found that 13.3% (89/671) of bats had...
We conducted a cross-sectional serosurvey for chikungunya virus (CHIKV) exposure in fruit bats in Senegal during 2020-2023. We found that 13.3% (89/671) of bats had CHIKV IgG; highest prevalence was in Eidolon helvum (18.3%, 15/82) and Epomophorus gambianus (13.7%, 63/461) bats. Our results suggest these bats are naturally exposed to CHIKV.
Topics: Animals; Chiroptera; Senegal; Chikungunya virus; Chikungunya Fever; Seroepidemiologic Studies; Antibodies, Viral; Cross-Sectional Studies
PubMed: 38916865
DOI: 10.3201/eid3007.240055 -
Emerging Infectious Diseases Jul 2024In October 2023, bluetongue virus serotype 3 (BTV-3) emerged in Germany, where Schmallenberg virus is enzootic. We detected BTV-3 in 1 pool of Culicoides biting midges...
In October 2023, bluetongue virus serotype 3 (BTV-3) emerged in Germany, where Schmallenberg virus is enzootic. We detected BTV-3 in 1 pool of Culicoides biting midges collected at the time ruminant infections were reported. Schmallenberg virus was found in many vector pools. Vector trapping and analysis could elucidate viral spread.
Topics: Animals; Ceratopogonidae; Bluetongue virus; Germany; Orthobunyavirus; Serogroup; Bluetongue; Bunyaviridae Infections; Insect Vectors
PubMed: 38916645
DOI: 10.3201/eid3007.240275 -
Emerging Infectious Diseases Jul 2024We analyzed West Nile Virus (WNV) exposure from 1,222 blood donors during 2017-2018 from an area of south-central Spain. Results revealed WNV seroprevalence of 0.08%...
We analyzed West Nile Virus (WNV) exposure from 1,222 blood donors during 2017-2018 from an area of south-central Spain. Results revealed WNV seroprevalence of 0.08% (95% CI 0.004%-0.4%) in this population. Our findings underscore the need for continued surveillance and research to manage WNV infection in this region.
Topics: Humans; Spain; Blood Donors; West Nile Fever; West Nile virus; Seroepidemiologic Studies; Male; Female; Adult; Middle Aged; Antibodies, Viral; Young Adult; Adolescent; Aged
PubMed: 38916587
DOI: 10.3201/eid3007.240450 -
Emerging Infectious Diseases Jul 2024Crimean-Congo hemorrhagic fever (CCHF) is a lethal viral disease that has severe public health effects throughout Africa and a case fatality rate of 10%-40%. CCHF virus... (Review)
Review
Crimean-Congo hemorrhagic fever (CCHF) is a lethal viral disease that has severe public health effects throughout Africa and a case fatality rate of 10%-40%. CCHF virus was first discovered in Crimea in 1944 and has since caused a substantial disease burden in Africa. The shortage of diagnostic tools, ineffective tick control efforts, slow adoption of preventive measures, and cultural hurdles to public education are among the problems associated with continued CCHF virus transmission. Progress in preventing virus spread is also hampered by the dearth of effective serodiagnostic testing for animals and absence of precise surveillance protocols. Intergovernmental coordination, creation of regional reference laboratories, multiinstitutional public education partnerships, investments in healthcare infrastructure, vaccine development, and a One Health approach are strategic methods for solving prevention challenges. Coordinated efforts and financial commitments are needed to combat Crimean-Congo hemorrhagic fever and improve all-around readiness for newly developing infectious illnesses in Africa.
Topics: Hemorrhagic Fever, Crimean; Humans; Africa; Hemorrhagic Fever Virus, Crimean-Congo; Animals; Ticks
PubMed: 38916548
DOI: 10.3201/eid3007.230810 -
Frontiers in Public Health 2024Health statistics on dengue are virtually non-existent, despite the fact that the virus is circulating in Togo. This study aimed to assess the knowledge, attitudes, and...
Knowledge, attitudes, and practices of health care professionals regarding dengue fever: need for training and provision of diagnostic equipment in Togo in 2022, a cross-sectional study.
BACKGROUND
Health statistics on dengue are virtually non-existent, despite the fact that the virus is circulating in Togo. This study aimed to assess the knowledge, attitudes, and practices (KAP) of health professionals in the Kara health region.
METHODS
A cross-sectional study was conducted from March to June 2022 among healthcare professionals who had worked in the Kara region of northern Togo were selected using an exhaustive recruitment method. Data were collected by trained resident doctors with a face-to-face interview using a standardized, pretested questionnaire based on the WHO 2009 dengue guide. Three multivariate regression models were utilized to investigate factors associated with knowledge, attitudes and, and practices.
RESULTS
A total of 464 respondents (37.1% female), median age 35 years, interquartile range (29-43 years) were included. Only (3.0%) of the participants had received training on dengue fever diagnosis, treatment and prevention in the last 3 years, and 10.3% had dengue rapid diagnostic tests available at their hospital. Half of the respondents (49.1%) had good knowledge of dengue fever, compared with 30.0% who had positive attitudes. Of a total of 256 professionals who had encountered a case of dengue fever in their practice, only 24 (9.4%) had appropriate practices for diagnosing and treating dengue fever. In multivariate analysis, the healthcare professionals who had taken part in ongoing training on dengue fever were more likely to have adequate dengue diagnosis and treatment practice aOR = 8.1; CI 95% = [1.7-36.0].
CONCLUSION
Strengthening healthcare professionals' dengue-related skills through ongoing training and the provision of dengue diagnostic tests could help improve early detection practices and management of dengue fever in Togo.
Topics: Humans; Cross-Sectional Studies; Togo; Female; Male; Adult; Dengue; Health Knowledge, Attitudes, Practice; Surveys and Questionnaires; Health Personnel; Middle Aged
PubMed: 38915751
DOI: 10.3389/fpubh.2024.1375773 -
PloS One 2024Tick-borne encephalitis (TBE) is usually diagnosed based on the presence of TBE virus (TBEV)-specific IgM and IgG antibodies in serum. However, antibodies induced by...
Tick-borne encephalitis (TBE) is usually diagnosed based on the presence of TBE virus (TBEV)-specific IgM and IgG antibodies in serum. However, antibodies induced by vaccination or cross-reactivity to previous flavivirus infections may result in false positive TBEV serology. Detection of TBEV RNA may be an alternative diagnostic approach to detect viral presence and circumvent the diagnostic difficulties present when using serology. Viral RNA in blood is commonly detectable only in the first viremic phase usually lasting up to two weeks, and not in the second neurologic phase, when the patients contact the health care system and undergo diagnostic work-up. TBEV RNA has previously been detected in urine in a few retrospective TBE cases in the neurologic phase, and furthermore RNA of other flaviviruses has been detected in patient saliva. In this study, blood, saliva and urine were collected from 31 hospitalised immunocompetent patients with pleocytosis and symptoms of aseptic meningitis and/or encephalitis, suspected to have TBE. We wanted to pursue if molecular testing of TBEV RNA in these patient materials may be useful in the diagnostics. Eleven of the 31 study patients were diagnosed with TBE based on ELISA detection of TBEV specific IgG and IgM antibodies. None of the study patients had TBEV RNA detectable in any of the collected patient material.
Topics: Humans; Encephalitis, Tick-Borne; Encephalitis Viruses, Tick-Borne; Saliva; RNA, Viral; Male; Female; Middle Aged; Adult; Aged; Immunoglobulin M; Immunoglobulin G; Antibodies, Viral; Aged, 80 and over; Immunocompetence; Hospitalization
PubMed: 38913668
DOI: 10.1371/journal.pone.0305603 -
Infection, Genetics and Evolution :... Jun 2024Hainan Island and the Leizhou Peninsula, the southernmost part of mainland China, are areas where Aedes aegypti and Ae. albopictus are sympatric and are also...
BACKGROUND
Hainan Island and the Leizhou Peninsula, the southernmost part of mainland China, are areas where Aedes aegypti and Ae. albopictus are sympatric and are also high-incidence areas of dengue outbreaks in China. Many studies have suggested that Aedes endogenous viral components (EVEs) are enriched in piRNA clusters which can silence incoming viral genomes. Investigation the EVEs present in the piRNA clusters associated with viral infection of Aedes mosquitoes in these regions may provide a theoretical basis for novel transmission-blocking vector control strategies.
METHODS
In this study, specific primers for endogenous Flaviviridae elements (EFVEs) and endogenous Rhabdoviridae elements (ERVEs) were used to detect the distribution of Zika virus infection associated EVEs in the genomes of individuals of the two Aedes mosquitoes. Genetic diversity of EVEs with a high detection rate was also analyzed.
RESULTS
The results showed that many EVEs associated with Zika virus infection were detected in both Aedes species, with the detection rates were 47.68% to 100% in Ae. aegypti and 36.15% to 92.31% in sympatric Ae. albopictus populations. EVEs detection rates in another 17 Ae. albopictus populations ranged from 29.39% to 89.85%. Genetic diversity analyses of the four EVEs (AaFlavi53, AaRha61, AaRha91 and AaRha100) of Ae. aegypti showed that each had high haplotype diversity and low nucleotide diversity. The number of haplotypes in AaFlavi53 was 8, with the dominant haplotype being Hap_1 and the other 7 haplotypes being further mutated from Hap_1 in a lineage direction. In contrast, the haplotype diversity of the other three ERVEs (AaRha61, AaRha91 and AaRha100) was more diverse and richer, with the haplotype numbers were 9, 15 and 19 respectively. In addition, these EVEs all showed inconsistent patterns of both population differentiation and dispersal compared to neutral evolutionary genes such as the Mitochondrial COI gene.
CONCLUSION
The EFVEs and ERVEs tested were present at high frequencies in the field Aedes mosquito populations. The haplotype diversity of the EFVE AaFlavi53 was relatively lower and the three ERVEs (AaRha61, AaRha91, AaRha100) were higher. None of the four EVEs could be indicative of the genetic diversity of the Ae. aegypti population. This study provided theoretical support for the use of EVEs to block arbovirus transmission, but further research is needed into the mechanisms by which these EVEs are antiviral to Aedes mosquitoes.
PubMed: 38909667
DOI: 10.1016/j.meegid.2024.105627