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A 56-year-old man receiving rituximab who had months of neurologic symptoms was found to have Jamestown Canyon virus in cerebrospinal fluid by clinical metagenomic sequencing. The patient died, and postmortem examination revealed extensive neuropathologic abnormalities. Deep sequencing enabled detailed characterization of viral genomes from the cerebrospinal fluid, cerebellum, and cerebral cortex.

The Chikungunya virus (CHIKV) presents global health challenges, with Brazil experiencing outbreaks since its introduction in 2014. In 2023, following a CHIKV outbreak in Minas Gerais (MG), social media was used to optimize an entomological survey aimed at identifying vectors and viral lineages and assessing insecticide resistance. Following Instagram posts, residents with suspected CHIKV infection were able to schedule mosquito aspirations. In total, 421 mosquitoes (165 Aedes aegypti and 256 Culex quinquefasciatus) were captured from 40 households in Salinas city (MG) and tested for the Dengue, Zika, and Chikungunya viruses through RT-qPCR. Twelve of 57 pools (10 Ae. aegypti and two Cx. quinquefasciatus) tested positive for CHIKV RNA. Viral RNA was also detected in the heads of nine Ae. aegypti, indicating viral dissemination but not in Cx. quinquefasciatus. Genome sequencing yielded the first near-complete genome from the 2023 outbreak, unveiling that the CHIKV strain belonged to the East/Central/South African (ECSA) genotype. Additionally, genetic analyses revealed high frequencies of kdr alleles, including in CHIKV-infected mosquitoes, suggesting resistance to pyrethroid insecticides in this Ae. aegypti population. Social media was important for guiding mosquito-capture efforts in CHIKV transmission hotspots, thus optimizing the opportunity for viral detection. These findings emphasize the urgent need for innovative vector studies and control strategies, as well as interdisciplinary approaches in public health interventions.

The incidence of chikungunya has dramatically surged worldwide in recent decades, imposing an expanding burden on public health. In recent years, South America, particularly Brazil, has experienced outbreaks that have ravaged populations following the rapid dissemination of the chikungunya virus (CHIKV), which was first detected in 2014. The primary vector for CHIKV transmission is the urban mosquito species Aedes aegypti, which is highly prevalent throughout Brazil. However, the impact of the locally circulating CHIKV genotypes and specific combinations of local mosquito populations on vector competence remains unexplored. Here, we experimentally analyzed and compared the infectivity and transmissibility of the CHIKV-ECSA lineage recently isolated in Brazil among four Ae. aegypti populations collected from different regions of the country. When exposed to CHIKV-infected AG129 mice for blood feeding, all the mosquito populations displayed high infection rates and dissemination efficiency. Furthermore, we observed that all the populations were highly efficient in transmitting CHIKV to a vertebrate host (naïve AG129 mice) as early as eight days post-infection. These results demonstrate the high capacity of Brazilian Ae. aegypti populations to transmit the locally circulating CHIKV-ECSA lineage. This observation could help to explain the high prevalence of the CHIKV-ECSA lineage over the Asian lineage, which was also detected in Brazil in 2014. However, further studies comparing both lineages are necessary to gain a better understanding of the vector’s importance in the epidemiology of CHIKV in the Americas.

West Nile Virus (WNV) is an arbovirus endemic to many countries and has caused over 56,000 cases, with 2776 deaths in the U.S. from 1999 to 2022. WNV occurs most often in the fall, typically affecting elderly populations in states like Nebraska and Arizona. Currently, supportive care is the only management for WNV. Our case is a female patient in her mid-70s in an intermountain state who presented in the fall with WNV meningoencephalitis and experienced a delay in care due to the unique clinical presentation. This demonstrates the importance of early inclusion of WNV in the differential for altered mental status, especially with WNV risk factors, and expedition of supportive care. Doing so could potentially reduce antibiotic duration and hospital costs.

Powassan virus (POWV) is a tick-borne flavivirus endemic in North America and Russia. Experimental infections with POWV have confirmed horizontal, transstadial, vertical, and cofeeding transmission routes for potential virus maintenance. In the field, vertical transmission has never been observed. During New York State tick-borne pathogen surveillance, POWV RNA and/or infectious POWV was detected in five pools of questing Ixodes scapularis larvae. Additionally, engorged female I. scapularis adults were collected from hunter-harvested white-tailed deer (Odocoileus virginianus) in a region with relatively high tick infection rates of POWV and allowed to oviposit under laboratory conditions. POWV RNA was detected in three female adult husks and one pool of larvae from a positive female. Infectious virus was isolated from all three RNA-positive females and the single positive larval pool. The detection of RNA and infectious virus in unfed questing larvae from the field and larvae from replete females collected from the primary tick host implicates vertical transmission as a potential mechanism for the maintenance of POWV in I. scapularis in nature, and elucidates the potential epidemiological significance of larval ticks in the transmission of POWV to humans.

Arbovírus são transmitidos por mosquitos e carrapatos, causando doenças graves em humanos, como dengue, Zika, Chikungunya e febre amarela. Este estudo buscou padronizar a técnica de RT-qPCR para detecção desses vírus em amostras de tecidos parafinados. Foram utilizadas 45 amostras parafinadas, incluindo arbovírus em estudo e amostras de controle negativo, provenientes de diferentes períodos e tecidos, catalogadas pelo Instituto Evandro Chagas. A padronização da técnica de RT-qPCR é essencial para a vigilância epidemiológica de arbovírus na região amazônica e no Brasil. Os resultados demonstraram eficiência na detecção e quantificação do genoma viral dos diferentes arbovírus. A técnica de RT-qPCR se mostrou uma ferramenta importante para o diagnóstico diferencial em amostras de tecidos parafinados. Essa padronização é relevante para o monitoramento e controle efetivo das doenças transmitidas por arbovírus, contribuindo para a saúde pública e a prevenção de surtos. Este estudo ressalta a importância da padronização da técnica de RT-qPCR para detecção de arbovírus em amostras de tecidos parafinados. A região amazônica e o Brasil são áreas propensas a surtos dessas doenças, tornando esses avanços ainda mais significativos. A detecção precoce e precisa dos arbovírus permite a implementação de medidas de controle e prevenção mais eficazes, além de contribuir para a compreensão da epidemiologia dessas doenças.

ABSTRACT Aedes aegypti mosquitoes can transmit several arboviruses, including chikungunya virus (CHIKV), dengue virus (DENV), and Zika virus (ZIKV). When blood-feeding on a virus-infected human, the mosquito ingests the virus into the midgut (stomach), where it replicates and must overcome the midgut barrier to disseminate to other organs and ultimately be transmitted via the saliva. Current tools to study mosquito-borne viruses (MBVs) include 2D-cell culture systems and in vivo mosquito infection models, which offer great advantages, yet have some limitations. Here, we describe a long-term ex vivo culture of Ae. aegypti guts. Cultured guts were metabolically active for 7 d in a 96-well plate at 28°C and were permissive to ZIKV, DENV, Ross River virus, and CHIKV. Ex vivo guts from Culex pipiens mosquitoes were found to be permissive to Usutu virus. Immunofluorescence staining confirmed viral protein synthesis in CHIKV-infected guts of Ae. aegypti. Furthermore, fluorescence microscopy revealed replication and spread of a reporter DENV in specific regions of the midgut. In addition, two known antiviral molecules, β-d-N4-hydroxycytidine and 7-deaza-2′-C-methyladenosine, were able to inhibit CHIKV and ZIKV replication, respectively, in the ex vivo model. Together, our results show that ex vivo guts can be efficiently infected with mosquito-borne alpha- and flaviviruses and employed to evaluate antiviral drugs. Furthermore, the setup can be extended to other mosquito species. Ex vivo gut cultures could thus be a new model to study MBVs, offering the advantage of reduced biosafety measures compared to infecting living mosquitoes. IMPORTANCE Mosquito-borne viruses (MBVs) are a significant global health threat since they can cause severe diseases in humans, such as hemorrhagic fever, encephalitis, and chronic arthritis. MBVs rely on the mosquito vector to infect new hosts and perpetuate virus transmission. No therapeutics are currently available. The study of arbovirus infection in the mosquito vector can greatly contribute to elucidating strategies for controlling arbovirus transmission. This work investigated the infection of guts from Aedes aegypti mosquitoes in an ex vivo platform. We found several MBVs capable of replicating in the gut tissue, including viruses of major health importance, such as dengue, chikungunya, and Zika viruses. In addition, antiviral compounds reduced arbovirus infection in the cultured gut tissue. Overall, the gut model emerges as a useful tool for diverse applications such as studying tissue-specific responses to virus infection and screening potential anti-arboviral molecules.

Arbovirus emergence and epidemic potential, as approximated by the vectorial capacity formula, depends on host and vector parameters, including the vector’s intrinsic ability to replicate then transmit the pathogen known as vector competence. Vector competence is a complex, time-dependent, quantitative phenotype influenced by biotic and abiotic factors. A combination of experimental and modelling approaches is required to assess arbovirus intra-vector dynamics and estimate epidemic potential. In this study, we measured infection, dissemination, and transmission dynamics of chikungunya virus (CHIKV) in a field-derived Aedes albopictus population (Lyon, France) after oral exposure to a range of virus doses spanning human viraemia. Statistical modelling indicates rapid and efficient CHIKV progression in the vector mainly due to an absence of a dissemination barrier, with 100% of the infected mosquitoes ultimately exhibiting a disseminated infection, regardless of the virus dose. Transmission rate data revealed a time-dependent, but overall weak, transmission barrier, with individuals transmitting as soon as 2 days post-exposure (dpe) and >50% infectious mosquitoes at 6 dpe for the highest dose. Based on these experimental intra-vector dynamics data, epidemiological simulations conducted with an agent-based model showed that even at low mosquito biting rates, CHIKV could trigger outbreaks locally. Together, this reveals the epidemic potential of CHIKV upon transmission by Aedes albopictus in mainland France.

Previously unknown pathogens often emerge from primary ecosystems, but there is little knowledge on the mechanisms of emergence. Most studies analyzing the influence of land-use change on pathogen emergence focus on a single host–pathogen system and often observe contradictory effects. Here, we studied virus diversity and prevalence patterns in natural and disturbed ecosystems using a multi-host and multi-taxa approach. Mosquitoes sampled along a disturbance gradient in Côte d’Ivoire were tested by generic RT-PCR assays established for all major arbovirus and insect-specific virus taxa including novel viruses previously discovered in these samples based on cell culture isolates enabling an unbiased and comprehensive approach. The taxonomic composition of detected viruses was characterized and viral infection rates according to habitat and host were analyzed. We detected 331 viral sequences pertaining to 34 novel and 15 previously identified viruses of the families Flavi-, Rhabdo-, Reo-, Toga-, Mesoni- and Iflaviridae and the order Bunyavirales. Highest host and virus diversity was observed in pristine and intermediately disturbed habitats. The majority of the 49 viruses was detected with low prevalence. However, nine viruses were found frequently across different habitats of which five viruses increased in prevalence towards disturbed habitats, in congruence with the dilution effect hypothesis. These viruses were mainly associated with one specific mosquito species (Culex nebulosus), which increased in relative abundance from pristine (3%) to disturbed habitats (38%). Interestingly, the observed increased prevalence of these five viruses in disturbed habitats was not caused by higher host infection rates but by increased host abundance, an effect tentatively named abundance effect. Our data show that host species composition is critical for virus abundance. Environmental changes that lead to an uneven host community composition and to more individuals of a single species are a key driver of virus emergence.

In early 2020, Argentina experienced the worst dengue outbreak in its history, concomitant with first-to-date increasing COVID-19 cases. Dengue epidemics in temperate Argentina have already been described as spatially heterogeneous; in the previous 2016 outbreak, transmission occurred 7.3 times more frequently in slums compared to the rest of Buenos Aires City (CABA). These informal settlements have deficient sanitary conditions, precarious housing and high incidence of social vulnerabilities. The purpose of this work was to study the spatio-temporal patterns of the 2020 dengue epidemic in CABA in relation to socio-economic living conditions of its inhabitants and its interaction with the onset of COVID-19. The study considered the period between Jan 1st and May 30th 2020. Dengue and COVID-19 databases were obtained from the National Health Surveillance System; each record was anonymized and geo-localized. The city was divided according to census tracts and grouped in four socio-economic strata: slums, high, mid and low residential. An aligned-rank transform ANOVA was performed to test for differences in the incidence of dengue and COVID-19, and age at death due to COVID-19, among socio-economic strata, four age categories and their interaction. The incidence by cluster was calculated with a distance matrix up to 600 m from the centroid. Spatial joint dengue and COVID-19 risk was estimated by multiplying the nominal risk for each disease, defined from 1 (low) to 5 (high) according to their quantiles. During the study period, 7,175 dengue cases were registered in CABA (incidence rate 23.3 cases per 10,000 inh), 29.2% of which occurred in slums. During the same period, 8,809 cases of COVID-19 were registered (28.6 cases per 10,000 inh); over half (51.4%) occurred in slums, where the median age of cases (29 years old) was lower than in residential areas (42 years old). The mean age of the deceased was 58 years old in slums compared to 79 years old outside. The percentage of deaths in patients under 60 years old was 56% in slums compared to 8% in the rest of the city. The incidence of both diseases was higher in slums than in residential areas for most age categories. Spatial patterns were heterogeneous: dengue presented higher incidence values in the southern sector of the city and the west, and low values in highly urbanized quarters, whereas COVID-19 presented higher values in the east, south, high populated areas and slums. The lowest joint risk clusters were located mainly in high residential areas, whereas high joint risk was observed mainly in the south, some western clusters, the historical part of the city and center north. The social epidemiological perspective of dengue and COVID-19 differed, given that socio environmental heterogeneity influenced the burden of both viruses in a different manner. Despite the overwhelming effect of the COVID-19 pandemic, health care towards other diseases, especially in territories with pre-existing vulnerabilities, should not be unattended.

Background: After several years without bluetongue disease, a ruminant illness caused by Culicoides-borne bluetongue virus (BTV), two new autochthonous cases were reported in 2018 in Germany. By contrast, Schmallenberg virus (SBV), another Culicoides-borne virus pathogenic to ruminants, has continuously circulated in Germany since its first emergence in 2011. The disease outbreaks have triggered numerous studies on the biology of the Culicoides vectors, but many ecological details are still obscure. Methods: Culicoides biting midge species were collected with UV-light traps on 10 farms in Germany, with one trap inside and one trap outside barns on each of the farms. Traps were run once a week for 24 h from January to December 2019. Collected biting midges were morphologically identified, counted and statistically evaluated, with a focus on the Obsoletus Group and the Pulicaris Complex of the ceratopogonid genus Culicoides, which are believed to contain the major virus vectors. Temperature and relative humidity recorded at each trap were linked to the quantity of caught Culicoides. Correlations between relative Culicoides abundance and presence of livestock or type of husbandry were also investigated. Results: A total of 38,886 Culicoides biting midges were trapped, with most of them belonging to the Obsoletus Group (51.0%) and the Pulicaris Complex (38.8%). The majority of captured specimens were collected in traps inside the barns. Obsoletus Group individuals were caught from late January to the last week of December while Pulicaris Complex individuals were captured from the end of March to early December. The lowest average temperatures at which members of the two groups were collected were 10.7 °C and 12.8 °C, respectively. While temperature had a statistically significant effect on the activity of both the Obsoletus Group and the Pulicaris Complex, relative humidity only significantly affected the activity of the latter. The presence of livestock significantly influenced the number of captured Obsoletus Group, but not of Pulicaris Complex specimens. Inside the barns, no statistical difference was found between numbers of caught Obsoletus Group and Pulicaris Complex specimens in livestock holdings with deep litter and manure scraper or slatted floor husbandry systems. Conclusions: The almost year-round presence of Obsoletus Group biting midges and the demonstrated high relative abundance of other potential Culicoides vector species inside barns suggest a high risk of indoor virus transmission to ruminants should BTV or SBV circulate locally. Appropriate structural, organisational and vector control measures to reduce biting midge exposure should be implemented. [ABSTRACT FROM AUTHOR]

Background: Accurate case report data are essential to understand arbovirus dynamics, including spread and evolution of arboviruses such as Zika, dengue and chikungunya viruses. Giving the multi-country nature of arbovirus epidemics in the Americas, these data are not often accessible or are reported at different time scales (weekly, monthly) from different sources. Results: We developed a publicly available and user-friendly database for arboviral case data in the Americas: ARCA. ARCA is a relational database that is hosted on the ARCA website. Users can interact with the database through the website by submitting queries through the website, which generates displays results and allows users to download these results in different, convenient file formats. Users can choose to view arboviral case data through a table which containscontaining the number of cases for a particular week, a plot, or through a map. Conclusion: Our ARCA database is a useful tool for arboviral epidemiology research allowing for complex queries, data visualization, integration, and formatting. [ABSTRACT FROM AUTHOR]

• Bovine ephemeral fever virus (BEFV) is a significant arthropod-borne RNA virus. • A commercial live attenuated vaccine is widely used for BEF prevention. • No recent data exist regarding this vaccine effectiveness. • We demonstrated 60 % effectiveness of this vaccine in a field controlled study. • Mortality in unvaccinated was 2.6 % (7/311) vs. 0/120 among vaccinated. Bovine ephemeral fever virus (BEFV) is a globally spread arthropod-borne RNA virus that has significant economic impacts on the cattle industry. A live attenuated commercial BEF vaccine, based on the Australian BEFV strain 919, is widely used in Israel and other countries. A previous study has suggested the high effectiveness of this vaccine (ULTRAVAC BEF VACCINE™ from Zoetis®), but anecdotal reports of high BEF morbidity among vaccinated dairy herds in Israel casted doubt on these findings. To resolve this uncertainty, a randomized controlled field vaccine effectiveness study was conducted in Israel during a BEF outbreak which occurred in 2021. Eleven dairy herds were enrolled and monitored for BEF-associated morbidity and rumination alteration patterns using electronic monitoring tags (HR Tags, SCR® Dairy, Netanya, Israel). Four of the herds were naturally infected with BEFV during the outbreak, resulting in a total of 120 vaccinated and 311 unvaccinated subjects that were included in the effectiveness study. A mixed-effect Cox proportional hazard regression model was used to calculate the overall hazard ratio between vaccinated and unvaccinated cattle. This analysis demonstrated an average vaccine effectiveness of 60 % (95 % CI = 38 %–77 %) for preventing clinical disease. In addition, a non-statistically significant trend (p = 0.1) towards protection from mortality was observed, with no observation of mortality among the vaccinated groups compared to 2.61 % mortality (7/311) among the unvaccinated subjects. One hundred and thirty vaccinated and unvaccinated calves from affected and non-affected herds and with different status of morbidity were sampled and analysed by serum-neutralization test. The highest titers of BEFV-neutralizing antibodies were found in subjects that were both vaccinated and clinically affected, indicating a booster effect after vaccination. The results of the study provide evidence for the moderate effectiveness of the ULTRAVAC BEF VACCINE™ for the prevention of BEF. [ABSTRACT FROM AUTHOR]

Flaviviruses are a diverse group of RNA viruses, which include the etiological agents of Zika, dengue and yellow fever that are transmitted by mosquitoes. Flaviviruses do not encode reverse transcriptase and cannot reverse transcribe into DNA, yet DNA sequences of flaviviruses are found both integrated in the chromosomes of Aedes aegypti mosquitoes and as extrachromosomal sequences. We have previously examined the Ae. aegypti reference genome to identify flavivirus integrations and analyzed conservation of these sequences among whole-genome data of 464 Ae. aegypti collected across 10 countries globally. Here, we extended this analysis by identifying flavivirus sequences in these samples independently of the Ae. aegypti reference assembly. Our aim was to identify the complete set of viral sequences, including those absent in the reference genome, and their geographical distribution. We compared the identified sequences using BLASTn and applied machine learning methods to identify clusters of similar sequences. Apart from clusters of sequences that correspond to the four viral integration events that we had previously described, we identified 19 smaller clusters. The only cluster with a strong geographic association consisted of Cell-fusing agent virus-like sequences specific to Thailand. The remaining clusters did not have a geographic association and mostly consisted of near identical short sequences without strong similarity to any known flaviviral genomes. The short read sequencing data did not permit us to determine whether identified sequences were extrachromosomal or integrated into Ae. aegypti chromosomes. Our results suggest that Liverpool strain and field Ae. aegypti mosquitoes have a similar variety of conserved flaviviral DNA, whose functional role should be investigated in follow-up studies. [ABSTRACT FROM AUTHOR]

Dengue has long been a serious health burden to the global community, especially for those living in the tropics. Despite the availability of vaccines, effective treatment for the infection is still needed and currently remains absent. In the present study, the antiviral properties of the Streptomyces sp. KSF 103 methanolic extract (Streptomyces KSF 103 ME), which consists of a number of potential antiviral compounds, were investigated against dengue virus serotype 2 (DENV-2). The effects of this extract against DENV-2 replication were determined using the quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Findings from the study suggested that the Streptomyces KSF 103 ME showed maximum inhibitory properties toward the virus during the virus entry stage at concentrations of more than 12.5 µg/mL. Minimal antiviral activities were observed at other virus replication stages; adsorption (42% reduction at 50 µg/mL), post-adsorption (67.6% reduction at 50 µg/mL), prophylactic treatment (68.4% and 87.7% reductions at 50 µg/mL and 25 µg/mL, respectively), and direct virucidal assay (48% and 56.8% reductions at 50 µg/mL and 25 µg/mL, respectively). The Streptomyces KSF 103 ME inhibited dengue virus replication with a 50% inhibitory concentration (IC50) value of 20.3 µg/mL and an International System of Units (SI) value of 38.9. The Streptomyces KSF 103 ME showed potent antiviral properties against dengue virus (DENV) during the entry stage. Further studies will be needed to deduce the antiviral mechanisms of the Streptomyces KSF 103 ME against DENV. [ABSTRACT FROM AUTHOR]

Arboviruses have been shown to circulate in Madagascar, including West Nile, dengue, and chikungunya viruses, though the extent of their circulation remains poorly documented. We estimated the seroprevalence of these three arboviruses in Madagascar and determined risk factors associated with seropositivity. Serum samples obtained from 1680 individuals surrounding the Sentinel Health Centers network in all regions of the country were analyzed using ELISA and hemagglutination inhibition assays for dengue, chikungunya, and West Nile viruses IgG antibodies, and multivariate logistic regression models were run. Overall, 6.5% [IC 95% 3.2–9.9] were seropositive for dengue virus, predominantly of Dengue serotype 1, 13.7% [IC 95% 6.5–20.9] for chikungunya virus, and 12.7% [IC 95% 9.0–16.5] for West Nile virus. There was no association with age, showing that dengue and chikungunya viruses were likely recently introduced. Eastern and Northern parts were more affected by dengue and chikungunya viruses, while West Nile virus seemed to circulate in all parts of the country. Dengue and chikungunya seropositivity were notably associated with high levels of vegetation, as well as frequent work in the forest, and West Nile seropositivity with the presence of cultivated areas, as well as standard of living. This analysis gives a new insight into arboviruses circulation and transmission patterns in Madagascar. [ABSTRACT FROM AUTHOR]

Arboviruses are defined by their ability to replicate in both mosquito vectors and mammalian hosts. There is good evidence that arboviruses "prime" their progeny for infection of the next host, such as via differential glycosylation of their outer glycoproteins or packaging of host ribosomal subunits. We and others have previously shown that mosquito-derived viruses more efficiently infect mammalian cells than mammalian-derived viruses. These observations are consistent with arboviruses acquiring host-specific adaptations, and we hypothesized that a virus derived from either the mammalian host or mosquito vector elicits different responses when infecting the mammalian host. Here, we perform an RNA-sequencing analysis of the transcriptional response of Human Embryonic Kidney 293 (HEK-293) cells to infection with either mosquito (Aedes albopictus, C7/10)- or mammalian (Baby Hamster Kidney, BHK-21)-derived Sindbis virus (SINV). We show that the C7/10-derived virus infection leads to a more robust transcriptional response in HEK-293s compared to infection with the BHK-derived virus. Surprisingly, despite more efficient infection, we found an increase in interferon-β (IFN-β) and interferon-stimulated gene (ISG) transcripts in response to the C7/10-derived virus infection versus the BHK-derived virus infection. However, translation of interferon-stimulated genes was lower in HEK-293s infected with the C7/10-derived virus, starkly contrasting with the transcriptional response. This inhibition of ISG translation is reflective of a more rapid overall shut-off of host cell translation following infection with the C7/10-derived virus. Finally, we show that the C7/10-derived virus infection of HEK-293 cells leads to elevated levels of phosphorylated eukaryotic translation elongation factor-2 (eEF2), identifying a potential mechanism leading to the more rapid shut-off of host translation. We postulate that the rapid shut-off of host translation in mammalian cells infected with the mosquito-derived virus acts to counter the IFN-β-stimulated transcriptional response. [ABSTRACT FROM AUTHOR]

The Zika virus (ZIKV) is a widespread mosquito-borne pathogen. Phylogenetically, two lineages of ZIKV are distinguished: African and Asian–American. The latter became the cause of the 2015–2016 pandemic, with severe consequences for newborns. In West African countries, the African lineage was found, but there is evidence of the emergence of the Asian–American lineage in Cape Verde and Angola. This highlights the need to not only monitor ZIKV but also sequence the isolates. In this article, we present a case report of Zika fever in a pregnant woman from Guinea identified in 2018. Viral RNA was detected through qRT-PCR in a serum sample. In addition, the seroconversion of anti-Zika IgM and IgG antibodies was detected in repeated blood samples. Subsequently, the virus was isolated from the C6/36 cell line. The detected ZIKV belonged to the African lineage, the Nigerian sublineage. The strains with the closest sequences were isolated from mosquitoes in Senegal in 2011 and 2015. In addition, we conducted the serological screening of 116 blood samples collected from patients presenting to the hospital of Faranah with fevers during the period 2018–2021. As a result, it was found that IgM-positive patients were identified each year and that the seroprevalence varied between 5.6% and 17.1%. [ABSTRACT FROM AUTHOR]

Mosquitoes (Diptera, Culicidae) are a very diverse taxonomic group, which mainly inhabits tropical-subtropical zones, with many species of public health significance considered vectors of different pathogens, such as the yellow fever virus (YFV) (Flavivirus, Flaviviridae). Our aim is to know the diversity of mosquito species in the Upper Paraná Atlantic Forest and determine the presence of vector of YFV. The study was carried out in April and November 2021 in three Provincial Parks: Piñalito, Cruce Caballero and Moconá. We used CDC-light traps and net/manual aspirator as collection techniques. Overall, across the three sites we collected 536 female adult mosquitoes and identified 13 genera and 33 species. Considering all study sites, we obtained a high Margalef diversity index (DMG=5.8). Considering all study sites together, the species with the highest relative abundance (RA) were Haemagogus leucocelaenus (Dyar and Shannon) (RA=15.3%, N=37) and Psorophora ferox (von Humboldt) (RA=16.1%, N=39). In relation to species involved in the sylvatic YF cycle, we collected Hg. leucocelaenus (a main vectors) in the three study areas and nine other species considered potential vectors (7 species in Piñalito, 5 in Cruce Caballero and 2 in Moconá). Although all of the species we found have been previously reported in Misiones, none had been documented in the studied areas; so, we expanded the distribution of all of them. We found a high diversity of species reported for Misiones (33 of 194 species), which could be related to the variety of habitats present in this portion of the Upper Paraná Atlantic Forest. In addition, many of these species are of sanitary importance, which makes these areas of special interest for developing plans to monitor insects and their associated viruses. [ABSTRACT FROM AUTHOR]

Mosquito-borne La Crosse virus (LACV; family: Peribunyaviridae) is the leading cause of pediatric arboviral encephalitis in the United States, with clinical cases generally centered in the Midwest and Appalachian regions. Incidence of LACV cases in Appalachian states has increased, such that the region currently represents the majority of reported LACV cases in the USA. The amount of reported LACV cases from Virginia, however, is minimal compared to neighboring states such as North Carolina, West Virginia, and Tennessee, and non-Appalachian regions of Virginia are understudied. Here we examine the hypothesis that LACV is circulating widely in Virginia, despite a low clinical case report rate, and that the virus is circulating in areas not associated with LACV disease. In this study, we screened local mammalian wildlife in northwestern counties of Virginia using passive surveillance via patients submitted to wildlife rehabilitation centers. Blood sera (527 samples; 9 species, 8 genera) collected between October 2019 and December 2022 were screened for neutralizing antibodies against LACV, indicating prior exposure to the virus. We found an overall LACV seroprevalence of 1.90% among all wild mammals examined and reveal evidence of LACV exposure in several wild species not generally associated with LACV, including eastern cottontails and red foxes, along with established reservoirs, eastern gray squirrels, although there was no serological evidence in chipmunks. These data indicate the circulation of LACV in Virginia outside of Appalachian counties, however, at a lower rate than reported for endemic areas within the state and in other states. [ABSTRACT FROM AUTHOR]

Arboviruses are transmitted by mosquitoes and ticks, causing severe diseases in humans such as dengue, Zika, Chikungunya, and yellow fever. This study aimed to standardize the RT-qPCR technique for detecting these viruses in paraffin-embedded tissue samples. A total of 45 paraffin-embedded samples were used, including arboviruses under study and negative control samples from different periods and tissues, cataloged by the Evandro Chagas Institute. Standardization of the RT-qPCR technique is essential for arbovirus surveillance in the Amazon region and Brazil. The results demonstrated efficiency in detecting and quantifying the viral genome of different arboviruses. The RT-qPCR technique proved to be an important tool for the differential diagnosis in paraffin-embedded tissue samples. This standardization is relevant for monitoring and effectively controlling arbovirus-transmitted diseases, contributing to public health and outbreak prevention. This study highlights the importance of standardizing the RT-qPCR technique for detecting arboviruses in paraffin-embedded tissue samples. The Amazon region and Brazil are prone to outbreaks of these diseases, making these advancements even more significant. Early and accurate detection of arboviruses enables the implementation of more effective control and prevention measures, as well as contributing to the understanding of the epidemiology of these diseases. [ABSTRACT FROM AUTHOR]

In Cuba is verified the circulation of several flaviviruses such as Dengue, St. Louis encephalitis, West Nile, Zika, among others. Viruses of the Flaviviridae family are the cause of diseases in birds and mammals, including humans. Bats could be important reservoirs of these viruses; several flaviviruses have been isolated from infected bats, including St. Louis encephalitis virus and Japanese encephalitis. In addition, 26 species of bats inhabit the island, of which 10 can use architectural structures as daytime shelters, so their colonies could be in close contact with humans. However, until date, few studies have carried out related to the search for zoonotic viruses in these mammals or their ectoparasites. The objective of this study was the search for flaviviruses in bats in a peri-urban area of the Havana province. Fifty bats were captured, 40 classified as Artibeus jamaicensis (family Phyllostomidae) and 10 as Molossus milleri (family Molossidae). Samples taken from each individual were studied by reverse transcription polymerase chain reaction (RT-PCR) and nested (RT-nested PCR). The presence of flavivirus was determined in one of the captured individuals belonging to the species Molossus milleri. This finding reported for the first time in Cuba, is of great epidemiological importance since this bat is a synanthropic species, and therefore has direct contact with humans. The identification of the reservoir bat species could be an important advance to achieve an effective program in the control and risk reduction of arboviral diseases. [ABSTRACT FROM AUTHOR]

The presence of alphaviruses, such as chikungunya virus (CHIKV), has never been reported in Mauritania. We assessed the seroprevalence of CHIKV among Nouakchott residents. A cross-sectional study involving 1300 non-febrile patients consulting at the Nouakchott hospital center was conducted between January and June 2021. The presence of anti-CHIKV IgG and neutralizing antibodies against CHIKV, O'nyong-nyong virus (ONNV), and Semliki Forest virus (SFV) was determined by an enzyme-linked immunosorbent assay (ELISA) and a serum neutralization test, respectively, and the associated risk factors were investigated. Of the 1300 study participants, serological evidence of previous exposure to CHIKV was observed in 37 individuals (2.8%). Sex, age, reported use of repellants, and bed net ownership and usage were not associated with CHIKV seropositivity. Our results showed the co-circulation of two other alphaviruses, ONNV and SFV, in Nouakchott in 30 (2.3%) individuals. This is the first study that documents the co-circulation of CHIKV, ONNV, and SFV in Mauritania, albeit at low prevalence. Surveillance and routine testing for alphaviruses and other arboviruses in symptomatic patients should be implemented in health facilities to assess the health burden associated with these viruses. Efforts should also be made to strengthen the vector control measures. [ABSTRACT FROM AUTHOR]

Background: Zika virus (ZIKV), first described in 1947, is an arthropod-borne virus associated with sporadic outbreaks and interepidemic transmission. Recent studies have implicated nonhuman primates (NHPs) as the probable reservoir hosts. We tested archived serum samples of NHPs collected in Kenya for evidence of neutralizing ZIKV antibodies. Methods: We randomly selected 212 archived serum samples from Institute of Primate Research in Kenya collected between 1992 and 2017. These specimens were tested by microneutralization test. Results: The 212 serum samples were collected in 7 counties from 87 (41.0%) Olive baboons, 69 (32.5%) Vervet monkeys, and 49 (23.1%) Sykes monkeys. Half (50.9%) were male and 56.4% were adult. We detected ZIKV antibodies in 38 (17.9%; 95% confidence interval: 13.3–23.6) samples. Conclusions: These results suggest ZIKV transmission and potential maintenance in nature by NHPs in Kenya. [ABSTRACT FROM AUTHOR]

Copyright of Revista Veterinaria is the property of Universidad Nacional del Nordeste and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effects of filter paper strip (FPS) storage time and temperature on antibody detection are poorly understood despite widespread use in wildlife research. We collected sera and FPSs from 23 wild turkeys (Meleagris gallopavo) and 20 northern bobwhites (Colinus virginianus) experimentally infected with West Nile virus (WNV) to compare FPS storage methods with WNV plaque reduction neutralization test (PRNT) sensitivity. FPS storage methods included: immediate elution after drying, and storage at −20°C for 3 mo, −20°C for 6 mo, room temperature (RT) for 3 mo, and RT for 6 mo prior to elution. FPS eluates and sera were co-titrated to determine endpoint antibody titers, which were compared between FPS sera eluted immediately and sera, and among FPS eluates that underwent different storage conditions. Antibody titers were ~4-fold less in FPS sera eluted immediately versus sera, and dropped more frequently below PRNT detection threshold in northern bobwhites, which had ~10-fold lower serum antibody titers than wild turkeys. Antibody titers were lower in FPS samples stored at RT and for 6 mo. WNV serologic surveys may result in falsely low seroprevalence estimates if FPSs are stored at RT for ≥ 3 mo before elution. [ABSTRACT FROM AUTHOR]

Copyright of Épidémiologie et Santé Animale is the property of Association pour l'Etude de l'Epidemiologie des Maladies Animales (AEEMA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: West Nile virus (WNV) and Usutu virus (USUV) are emerging zoonotic arboviruses sharing the same life cycle with mosquitoes as vectors and wild birds as reservoir hosts. The main objective of this study was to characterize the pathogenicity and course of infection of two viral strains (WNV/08 and USUV/09) co-circulating in Southern Spain in a natural host, the red-legged partridge (Alectoris rufa), and to compare the results with those obtained with the reference strain WNV/NY99. Methods: WNV inoculated birds were monitored for clinical and analytical parameters (viral load, viremia, and antibodies) for 15 days post-inoculation. Results and discussion: Partridges inoculated with WNV/NY99 and WNV/08 strains showed clinical signs such as weight loss, ruffled feathers, and lethargy, which were not observed in USUV/09-inoculated individuals. Although statistically significant differences in mortality were not observed, partridges inoculated with WNV strains developed significantly higher viremia and viral loads in blood than those inoculated with USUV. In addition, the viral genome was detected in organs and feathers of WNV-inoculated partridges, while it was almost undetectable in USUV-inoculated ones. These experimental results indicate that red-legged partridges are susceptible to the assayed Spanish WNV with pathogenicity similar to that observed for the prototype WNV/NY99 strain. By contrast, the USUV/09 strain was not pathogenic for this bird species and elicited extremely low viremia levels, demonstrating that red-legged partridges are not a competent host for the transmission of this USUV strain. [ABSTRACT FROM AUTHOR]

The development of virus-like particle (VLP) based vaccines for human papillomavirus, hepatitis B and hepatitis E viruses represented a breakthrough in vaccine development. However, for dengue and COVID-19, technical complications, such as an incomplete understanding of the requirements for protective immunity, but also limitations in processes to manufacture VLP vaccines for enveloped viruses to large scale, have hampered VLP vaccine development. Selecting the right adjuvant is also an important consideration to ensure that a VLP vaccine induces protective antibody and T cell responses. For diseases like COVID-19 and dengue fever caused by RNA viruses that exist as families of viral variants with the potential to escape vaccine-induced immunity, the development of more efficacious vaccines is also necessary. Here, we describe the development and characterisation of novel VLP vaccine candidates using SARS-CoV-2 and dengue virus (DENV), containing the major viral structural proteins, as protypes for a novel approach to produce VLP vaccines. The VLPs were characterised by Western immunoblot, enzyme immunoassay, electron and atomic force microscopy, and in vitro and in vivo immunogenicity studies. Microscopy techniques showed proteins self-assemble to form VLPs authentic to native viruses. The inclusion of the glycolipid adjuvant, α-galactosylceramide (α-GalCer) in the vaccine formulation led to high levels of natural killer T (NKT) cell stimulation in vitro, and strong antibody and memory CD8+ T cell responses in vivo, demonstrated with SARS-CoV-2, hepatitis C virus (HCV) and DEN VLPs. This study shows our unique vaccine formulation presents a promising, and much needed, new vaccine platform in the fight against infections caused by enveloped RNA viruses. [ABSTRACT FROM AUTHOR]

Zika virus (ZIKV) is an RNA flavivirus (Flaviviridae family) endemic in tropical and subtropical regions that is transmitted to humans by Aedes (Stegomyia) species mosquitoes. The two main urban vectors of ZIKV are Aedes aegypti and Aedes albopictus, which can be found throughout Brazil. This study investigated ZIKV infection in mosquito species sampled from urban forest fragments in Manaus (Brazilian Amazon). A total of 905 non-engorged female Ae. aegypti (22 specimens) and Ae. albopictus (883 specimens) were collected using BG-Sentinel traps, entomological hand nets, and Prokopack aspirators during the rainy and dry seasons between 2018 and 2021. All pools were macerated and used to inoculate C6/36 culture cells. Overall, 3/20 (15%) Ae. aegypti and 5/241 (2%) Ae. albopictus pools screened using RT-qPCR were positive for ZIKV. No supernatants from Ae. aegypti were positive for ZIKV (0%), and 15 out of 241 (6.2%) Ae. albopictus pools were positive. In this study, we provide the first-ever evidence of Ae. albopictus naturally infected with ZIKV in the Amazon region. [ABSTRACT FROM AUTHOR]

French Guiana (FG), a French overseas territory in South America, is susceptible to tropical diseases, including arboviruses. The tropical climate supports the proliferation and establishment of vectors, making it difficult to control transmission. In the last ten years, FG has experienced large outbreaks of imported arboviruses such as Chikungunya and Zika, as well as endemic arboviruses such as dengue, Yellow fever, and Oropouche virus. Epidemiological surveillance is challenging due to the differing distributions and behaviors of vectors. This article aims to summarize the current knowledge of these arboviruses in FG and discuss the challenges of arbovirus emergence and reemergence. Effective control measures are hampered by the nonspecific clinical presentation of these diseases, as well as the Aedes aegypti mosquito's resistance to insecticides. Despite the high seroprevalence of certain viruses, the possibility of new epidemics cannot be ruled out. Therefore, active epidemiological surveillance is needed to identify potential outbreaks, and an adequate sentinel surveillance system and broad virological diagnostic panel are being developed in FG to improve disease management. [ABSTRACT FROM AUTHOR]

Copyright of Arquivos de Ciências da Saúde da UNIPAR is the property of Associacao Paranaense de Ensino e Cultura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The continuous expansion of Aedes albopictus in Europe and the increases in autochthonous arboviruses transmissions in the region urge a better understanding of the virus transmission dynamic. Recent work described enhanced chikungunya virus (CHIKV) dissemination in Aedes aegypti mosquitoes exposed to a virus-free blood meal three days after their infection with CHIKV. Our study investigated the impact of a second blood meal on the vector competence of Ae. albopictus from southern Switzerland infected with CHIKV. Seven-day-old Ae. albopictus females were exposed to CHIKV-spiked blood and incubated at constant (27 °C) and fluctuating (14–28 °C) temperatures. Four days post-infection (dpi), some of these females were re-fed with a non-infectious blood meal. Virus infectivity, dissemination, transmission rate, and efficiency were investigated at seven and ten dpi. No enhanced dissemination rate was observed among females fed a second time; however, re-fed females have shown higher transmission efficiency than those fed only once after seven days post-infection and incubated under a fluctuating temperature regime. Vector competence for CHIKV was confirmed in Ae. albopictus from southern Switzerland. We did not observe an increase in dissemination rates among mosquitoes fed a second time (second blood meal), regardless of the temperature regime. [ABSTRACT FROM AUTHOR]

The "One Health" concept considers that human and animal health, and ecosystems are closely related and aims to make a link between ecology and human and veterinary medicine. Due to the explosion in population growth along with the geographic and climatic conditions (equatorial and/or tropical climate), Africa is becoming a major hotspot for various socio-health issues associated with infectious diseases, including arboviruses. The incontestable advantages of a One Health approach in Africa lie in the fight against pathogens, such as arboviruses, and in the preservation of environmental, animal, and human health to ensure that the increasing high needs of this population are met as well as their protection against potential epidemics. The One Health strategy gives us a glimpse of the difficulties and challenges that the African continent faces. The importance of this approach in Africa is to establish guidelines and strategies for effective solutions and changes in behavior and harmful activities. Overall, the establishment of high-quality global health policies in the framework of the global health standards program would provide healthy and sustainable human–animal–environmental interactions for the welfare of all. [ABSTRACT FROM AUTHOR]

Although fetal death is now understood to be a severe outcome of congenital Zika syndrome, the role of viral genetics is still unclear. We sequenced Zika virus (ZIKV) from a rhesus macaque fetus that died after inoculation and identified a single intrahost substitution, M1404I, in the ZIKV polyprotein, located in nonstructural protein 2B (NS2B). Targeted sequencing flanking position 1404 in 9 additional macaque mothers and their fetuses identified M1404I at a subconsensus frequency in the majority (5 of 9, 56%) of animals and some of their fetuses. Despite its repeated presence in pregnant macaques, M1404I has occurred rarely in humans since 2015. Since the primary ZIKV transmission cycle is human-mosquito-human, mutations in one host must be retained in the alternate host to be perpetuated. We hypothesized that ZIKV I1404 increases viral fitness in nonpregnant macaques and pregnant mice but is less efficiently transmitted by vectors, explaining its low frequency in humans during outbreaks. By examining competitive fitness relative to that of ZIKV M1404, we observed that ZIKV I1404 produced lower viremias in nonpregnant macaques and was a weaker competitor in tissues. In pregnant wild-type mice, ZIKV I1404 increased the magnitude and rate of placental infection and conferred fetal infection, in contrast to ZIKV M1404, which was not detected in fetuses. Although infection and dissemination rates were not different, Aedes aegypti mosquitoes transmitted ZIKV I1404 more poorly than ZIKV M1404. Our data highlight the complexity of arbovirus mutation-fitness dynamics and suggest that intrahost ZIKV mutations capable of augmenting fitness in pregnant vertebrates may not necessarily spread efficiently via mosquitoes during epidemics.IMPORTANCE Although Zika virus infection of pregnant women can result in congenital Zika syndrome, the factors that cause the syndrome in some but not all infected mothers are still unclear. We identified a mutation that was present in some ZIKV genomes in experimentally inoculated pregnant rhesus macaques and their fetuses. Although we did not find an association between the presence of the mutation and fetal death, we performed additional studies with ZIKV with the mutation in nonpregnant macaques, pregnant mice, and mosquitoes. We observed that the mutation increased the ability of the virus to infect mouse fetuses but decreased its capacity to produce high levels of virus in the blood of nonpregnant macaques and to be transmitted by mosquitoes. This study shows that mutations in mosquito-borne viruses like ZIKV that increase fitness in pregnant vertebrates may not spread in outbreaks when they compromise transmission via mosquitoes and fitness in nonpregnant hosts.

The sand fly-borne Toscana virus (TOSV) is the major cause of human meningoencephalitis in the Mediterranean basin during the summer season. In this work, we have developed a T7 RNA polymerase-driven reverse genetics system to recover infectious particles of a lineage B strain of TOSV. The viral protein pattern and growth properties of the rescued virus (rTOSV) were found to be similar to those of the corresponding wild-type (wt) virus. Using this system, we genetically engineered a TOSV mutant lacking expression of the non-structural protein NSs (rTOSVɸNSs). Unlike rTOSV and the wt virus, rTOSVɸNSs was unable to (i) suppress interferon (IFN)-b messenger RNA induction; and (ii) grow efficiently in cells producing IFN-b. Together, our results highlight the importance of NSs for TOSV in evading the IFN response and provide a comprehensive toolbox to investigate the TOSV life cycle in mammalian and insect host cells, including several novel polyclonal antibodies.

Land cover and land use change (LCLUC) acts as a catalyst for spillover of arthropod-borne pathogens into novel hosts by shifting host and vector diversity, abundance, and distribution, ultimately reshaping host-vector interactions. Identification of bloodmeals from wild-caught mosquitoes provides insight into host utilization of particular species in particular land cover types, and hence their potential role in pathogen maintenance and spillover. Here, we collected 134 blood-engorged mosquitoes comprising 10 taxa across 9 land cover types in Sarawak, Malaysian Borneo, a region experiencing intense LCLUC and concomitant spillover of arthropod-borne pathogens. Host sources of blood were successfully identified for 116 (87%) mosquitoes using cytochrome oxidase subunit I (COI) barcoding. A diverse range of hosts were identified, including reptiles, amphibians, birds, and mammals. Sixteen engorged Aedes albopictus, a major vector of dengue virus, were collected from seven land cover types and found to feed exclusively on humans (73%) and boar (27%). Culex tritaeniohynchus (n = 2), Cx. gelidus (n = 3), and Cx. quiquefasciatus (n = 3), vectors of Japanese encephalitis virus, fed on humans and pigs in the rural built-up land cover, creating potential transmission networks between these species. Our data support the use of COI barcoding to characterize mosquito-host networks in a biodiversity hotspot.

Abstract Background West Nile Virus is a single-stranded Ribonucleic Acid arbovirus of the Flaviviridae family that is transmitted to humans by Culex species mosquitoes. West Nile Virus infection is asymptomatic in the majority of affected people. Of those who develop symptoms, the usual manifestation is a febrile syndrome, while only 1% develop neurological symptoms due to a neuroinvasive form of infection, including encephalitis, meningitis, asymmetrical flaccid paralysis, or a combination of all these features. Parsonage–Turner syndrome is a rare disorder characterized by sudden painful symptoms and subsequent paralysis, involving a shoulder or one of the upper limbs due to post-infective brachial plexopathy. The etiology is unknown, although it can be considered a multifactorial process: a predisposing factor, such as viral infection or strenuous upper-extremity exercise, can trigger an immune-mediated process localized in the brachial plexus. Clinical presentation In late summer, a 79-year-old male Italian patient was admitted to the emergency department for acute right upper limb weakness and high fever, without any mental status impairment, pain, sensory alterations, or signs of meningeal irritation. Laboratory tests confirmed acute West Nile Virus infection, expressed as a unilateral upper limb flaccid paralysis. After a few days, the patient reported an acute pain in the right upper limb scarcely responsive to nonsteroidal anti-inflammatory drug therapy and a subsequent wider distribution of flaccid paralysis. After multiple examinations, Parsonage–Turner syndrome could be suspected. Patient was treated with steroids and reported an improvement of clinical condition after 2 months, with complete pain remission but partial strength recovery in the affected limb. Conclusions West Nile Virus disease has a broad spectrum of neurological manifestations, among which the most common are signs of meningeal irritation or cognitive impairment. We report an unusual presentation of neuroinvasive West Nile Virus infection with arm weakness as expression of unilateral viral neuritis, followed by a post-infective brachial plexopathy consistent with Parsonage–Turner syndrome diagnosis. We diagnosed Parsonage–Turner syndrome after excluding the most common causes of atraumatic acute upper limb pain, through a challenging differential diagnosis in a patient with several comorbidities.

RESUMO Este artigo apresenta reflexões sobre estratégias de educação em saúde para prevenção da Dengue, Zika e Chikungunya no âmbito do Programa Saúde na Escola (PSE), visando à atenção integral à saúde de estudantes do ensino público básico nas escolas, em parceria com as Unidades Básicas de Saúde. Trata-se de uma pesquisa nacional, oriunda de um projeto intitulado Arbocontrol, coordenado pela Faculdade de Ciências da Saúde da Universidade de Brasília, com apoio do Ministério da Saúde, com vistas ao combate e controle das arboviroses decorrentes do Aedes aegypti. De abordagem qualitativa, este estudo fundamenta-se no pensamento foucaultiano de biopolítica. Foram entrevistados 158 professores e 117 profissionais de saúde, de 16 municípios, nas 5 regiões brasileiras. Os resultados indicaram que, na execução do PSE, o saber comunitário não se incorpora nas ações. O modelo educacional conteudista estabelece, a priori, o que deve ser tratado; e a fragilidade na articulação intersetorial para o planejamento das ações tem dificultado sua eficácia. A educação em saúde ainda é entendida como processo informativo para o autocuidado, fomentado por estratégias biopolíticas de disciplinamento dos corpos dos sujeitos ou na constituição de suas subjetividades para o autocuidado, depositando neles a responsabilidade por sua saúde.

Abstract Background ASEAN (Association of Southeast Asian Nations) is composed of ten Southeast Asian countries bound by socio-cultural ties that promote regional peace and stability. South Asia, located in the southern subregion of Asia, includes nine countries sharing similarities in geographical and ethno-cultural factors. Chikungunya is one of the most significant problems in Southeast and South Asian countries. Much of the current chikungunya epidemic in Southeast Asia is caused by the emergence of a virus strain that originated in Africa and spread to Southeast Asia. Meanwhile, in South Asia, three confirmed lineages are in circulation. Given the positive correlation between research activity and the improvement of the clinical framework of biomedical research, this article aimed to examine the growth of chikungunya virus-related research in ASEAN and South Asian countries. Methods The Scopus database was used for this bibliometric analysis. The retrieved publications were subjected to a number of analyses, including those for the most prolific countries, journals, authors, institutions, and articles. Co-occurrence mapping of terms and keywords was used to determine the current state, emerging topics, and future prospects of chikungunya virus-related research. Bibliometrix and VOSviewer were used to analyze the data and visualize the collaboration network mapping. Results The Scopus search engine identified 1280 chikungunya-related documents published by ASEAN and South Asian countries between 1967 and 2022. According to our findings, India was the most productive country in South Asia, and Thailand was the most productive country in Southeast Asia. In the early stages of the study, researchers investigated the vectors and outbreaks of the chikungunya virus. In recent years, the development of antivirus agents has emerged as a prominent topic. Conclusions Our study is the first to present the growth of chikungunya virus-related research in ASEAN and South Asian countries from 1967 to 2022. In this study, the evaluation of the comprehensive profile of research on chikungunya can serve as a guide for future studies. In addition, a bibliometric analysis may serve as a resource for healthcare policymakers.

Rationale: Malaria and dengue are the most prevalent vector-borne diseases in tropical countries. Plasmodium parasite and dengue virus (DENV) concurrent infection is possible and often under-recognized in geographical areas where these infections are both endemic. Patients concern and diagnosis: We describe the first two cases of Plasmodium falciparum and DENV-3 co-infection in travelers returning to northeastern Italy from Burkina Faso during 2013-2014. Interventions: Malaria infection in both patients was treated with mefloquine. Due to the persistence of symptoms despite of the antimalaria treatment, dengue was also investigated; the treatment of dengue was symptomatic. Outcomes: The patients were discharged in good general condition. Lessons: The need for surveillance of potential malaria and dengue co-infection in travelers returning to Europe from endemic areas is highlighted, as infection with Plasmodium does not exclude arboviral co-infection.

Background & objectives: Dengue represents one of the most important arboviruses in public health, and its etiological agent is transmitted by the bite of dipterans of the genus Aedes. Every year this disease affects a large part of the population of the state of São Paulo in Brazil, particularly due to the availability of favorable environmental conditions for the growth and development of the vector mosquito. This study aimed to verify the distribution of urban arboviruses in the municipalities of the state of São Paulo and the successful experiences of municipal governments to reduce cases, to highlight strategies that have successfully culminated, and which can serve as a basis for prevention strategies. Methods: Information taken from government databases of the Ministry of Health and demographic data were used, where the incidence rate of 14 selected municipalities in the region of Vale do Paraíba between 2015 and 2019 was determined, and an attempt was made to evidence the strategies used to reduce cases. Results: High incidence rates were observed in 2015 and 2019 concerning the other years of the historical series, due to environmental factors and the variation in the circulating strain. Interpretation & conclusion: The observed data allowed us to infer that the prevention strategies recommended by the evaluated municipalities had a positive effect in the years 2016 to 2018, but unforeseen a priori factors culminated in epidemics, revealing the importance of implementing epidemiological studies using advanced mapping tools, as a way of to minimize the risk of future epidemics.

West Nile virus (WNV; Flavivirus, Flaviviridae) was introduced to New York State (NYS) in 1999 and rapidly expanded its range through the continental United States (US). Apart from the displacement of the introductory NY99 genotype with the WN02 genotype, there has been little evidence of adaptive evolution of WNV in the US. WNV NY10, characterized by shared amino acid substitutions R1331K and I2513M, emerged in 2010 coincident with increased WNV cases in humans and prevalence in mosquitoes. Previous studies demonstrated an increase in frequency of NY10 strains in NYS and evidence of positive selection. Here, we present updated surveillance and sequencing data for WNV in NYS and investigate if NY10 genotype strains are associated with phenotypic change consistent with an adaptive advantage. Results confirm a significant increase in prevalence in mosquitoes though 2018, and updated sequencing demonstrates a continued dominance of NY10. We evaluated NY10 strains in Culex pipiens mosquitoes to assess vector competence and found that the NY10 genotype is associated with both increased infectivity and transmissibility. Experimental infection of American robins (Turdus migratorius) was additionally completed to assess viremia kinetics of NY10 relative to WN02. Modelling the increased infectivity and transmissibility of the NY10 strains together with strain-specific viremia demonstrates a mechanistic basis for selection that has likely contributed to the increased prevalence of WNV in NYS.

Abstract Background Insecticide resistance (IR) monitoring is essential for evidence-based control of mosquito-borne diseases. While widespread pyrethroid resistance in Anopheles and Aedes species has been described in many countries, data for Papua New Guinea (PNG) are limited. Available data indicate that the local Anopheles populations in PNG remain pyrethroid-susceptible, making regular IR monitoring even more important. In addition, Aedes aegypti pyrethroid resistance has been described in PNG. Here, Anopheles and Aedes IR monitoring data generated from across PNG between 2017 and 2022 are presented. Methods Mosquito larvae were collected in larval habitat surveys and through ovitraps. Mosquitoes were reared to adults and tested using standard WHO susceptibility bioassays. DNA from a subset of Aedes mosquitoes was sequenced to analyse the voltage-sensitive sodium channel (Vssc) region for any resistance-related mutations. Results Approximately 20,000 adult female mosquitoes from nine PNG provinces were tested. Anopheles punctulatus sensu lato mosquitoes were susceptible to pyrethroids but there were signs of reduced mortality in some areas. Some Anopheles populations were also resistant to DDT. Tests also showed that Aedes. aegypti in PNG are resistant to pyrethroids and DDT and that there was also likelihood of bendiocarb resistance. A range of Vssc resistance mutations were identified. Aedes albopictus were DDT resistant and were likely developing pyrethroid resistance, given a low frequency of Vssc mutations was observed. Conclusions Aedes aegypti is highly pyrethroid resistant and also shows signs of resistance against carbamates in PNG. Anopheles punctulatus s.l. and Ae. albopictus populations exhibit low levels of resistance against pyrethroids and DDT in some areas. Pyrethroid-only bed nets are currently the only programmatic vector control tool used in PNG. It is important to continue to monitor IR in PNG and develop proactive insecticide resistance management strategies in primary disease vectors to retain pyrethroid susceptibility especially in the malaria vectors for as long as possible. Graphic abstract