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Phylogenetic analyses showed that the virus responsible for a May 2024 Oropouche fever outbreak in Cuba was closely related to viruses from Brazil in 2023. Pools of Ceratopogonidae spp. biting midges and Culex quinquefasciatus mosquitoes were positive for Oropouche viral RNA. No cases were severe. Virus extension to new areas may increase case numbers and severity [ABSTRACT FROM AUTHOR]

Alphavirus infections are transmitted by mosquitoes, but the mode of transmission for Mycobacterium ulcerans, which causes Buruli ulcer, is contested. Using notification data for Victoria, Australia, during 2017–2022, adjusted for incubation period, we show close alignment between alphavirus and Buruli ulcer seasons, supporting the hypothesis of mosquito transmission of M. ulcerans. [ABSTRACT FROM AUTHOR]

Spread of the Anopheles stephensi mosquito, an invasive malaria vector, threatens to put an additional 126 million persons per year in Africa at risk for malaria. To accelerate the early detection and rapid response to this mosquito species, confirming its presence and geographic extent is critical. However, existing molecular species assays require specialized laboratory equipment, interpretation, and sequencing confirmation. We developed and optimized a colorimetric rapid loop-mediated isothermal amplification assay for molecular An. stephensi species identification. The assay requires only a heat source and reagents and can be used with or without DNA extraction, resulting in positive color change in 30–35 minutes. We validated the assay against existing PCR techniques and found 100% specificity and analytical sensitivity down to 0.0003 ng of genomic DNA. The assay can successfully amplify single mosquito legs. Initial testing on samples from Marsabit, Kenya, illustrate its potential as an early vector detection and malaria mitigation tool. [ABSTRACT FROM AUTHOR]

The article focuses on the ongoing threat posed by malaria, underscored by approximately 247 million cases reported globally in 2021. Topics include the emergence and spread of Anopheles stephensi mosquitoes in Africa and the Arabian Peninsula, their resistance to insecticides, and their potential role in recent malaria outbreaks, raising concerns about their impact in the Mediterranean region and uncertainties surrounding their distribution in Yemen's high-prevalence malaria areas.

The invasive Anopheles stephensi mosquito has rapidly expanded in range in Africa over the past decade. Consistent with World Health Organization guidelines, routine entomologic surveillance of malaria vectors in Accra, Ghana, now includes morphologic and molecular surveillance of An. stephensi mosquitoes. We report detection of An. stephensi mosquitoes in Ghana. [ABSTRACT FROM AUTHOR]

The Anopheles stephensi mosquito is an invasive malaria vector recently reported in Djibouti, Ethiopia, Sudan, Somalia, Nigeria, and Ghana. The World Health Organization has called on countries in Africa to increase surveillance efforts to detect and report this vector and institute appropriate and effective control mechanisms. In Kenya, the Division of National Malaria Program conducted entomological surveillance in counties at risk for An. stephensi mosquito invasion. In addition, the Kenya Medical Research Institute conducted molecular surveillance of all sampled Anopheles mosquitoes from other studies to identify An. stephensi mosquitoes. We report the detection and confirmation of An. stephensi mosquitoes in Marsabit and Turkana Counties by using endpoint PCR and morphological and sequence identification. We demonstrate the urgent need for intensified entomological surveillance in all areas at risk for An. stephensi mosquito invasion, to clarify its occurrence and distribution and develop tailored approaches to prevent further spread.

We describe clinical and laboratory findings of 3 autochthonous cases of dengue in the Paris Region, France, during September–October 2023. Increasing trends in cases, global warming, and growth of international travel mean that such infections likely will increase during warm seasons in France, requiring stronger arbovirus surveillance networks.

During the 2019 Eastern equine encephalitis virus (EEEV) outbreak in Michigan, two 2-month old Mexican wolf pups experienced neurologic signs, lymphohistiocytic neutrophilic meningoencephalitis with neuronal necrosis and neuronophagia, and acute death. We identified EEEV by reverse transcription real-time PCR and in situ hybridization. Vector mosquitoes were trapped at the zoo.

Jamestown Canyon virus (JCV) is a mosquito-borne arbovirus that circulates in North America. We detected JCV in 4 pools of mosquitoes collected from midcoastal Maine, USA, during 2017–2019. Phylogenetic analysis of a JCV sequence obtained from Aedes cantator mosquitoes clustered within clade A, which also circulates in Connecticut, USA.

We describe the influence of seasonal meteorologic variations and rainfall events on Anopheles stephensi mosquito populations during a 40-month surveillance study at a US military base in Djibouti. Focusing surveillance and risk mitigation for An. stephensi mosquitoes when climatic conditions are optimal presents an opportunity for malaria prevention and control in eastern Africa. [ABSTRACT FROM AUTHOR]

We report a case of Dirofilaria immitis nematode infection in a dog imported from Venezuela that had been living for 2 years in Santiago, Chile, where this parasite had not been reported before. Our findings warrant surveillance for all dogs imported to Chile, given that suitable conditions exist for establishing this parasite.

We investigated dengue virus (DENV) and asymptomatic DENV infections in rural villages of Kampong Cham Province, Cambodia, during 2012 and 2013. We conducted perifocal investigations in and around households for 149 DENV index cases identified through hospital and village surveillance. We tested participants 0.5-30 years of age by using nonstructural 1 rapid tests and confirmed DENV infections using quantitative reverse transcription PCR or nonstructural 1-capture ELISA. We used multivariable Poisson regressions to explore links between participants' DENV infection status and household characteristics. Of 7,960 study participants, 346 (4.4%) were infected with DENV, among whom 302 (87.3%) were

We collected >40,000 mosquitoes from 5 provinces in South Africa during 2011-2018 and screened for zoonotic flaviviruses. We detected West Nile virus in mosquitoes from conservation and periurban sites and potential new mosquito vectors; Banzi virus was rare. Our results suggest flavivirus transmission risks are increasing in South Africa. [ABSTRACT FROM AUTHOR]

Reports of the expansion of the Asia malaria vector Anopheles stephensi mosquito into new geographic areas are increasing, which poses a threat to the elimination of urban malaria. Efficient surveillance of this vector in affected areas and early detection in new geographic areas is key to containing and controlling this species. To overcome the practical difficulties associated with the morphological identification of immature stages and adults of An. stephensi mosquitoes, we developed a species-specific PCR and a real-time PCR targeting a unique segment of the second internal transcribed spacer lacking homology to any other organism. Both PCRs can be used to identify An. stephensi mosquitoes individually or in pooled samples of mixed species, including when present in extremely low proportions (1:500). This study also reports a method for selective amplification and sequencing of partial ribosomal DNA from An. stephensi mosquitoes for their confirmation in pooled samples of mixed species. [ABSTRACT FROM AUTHOR]

Arbovirus epidemiology lacks efficient and timely surveillance systems with accurate outbreak alert signals. We devised a citywide integrated surveillance system combining entomologic, epidemiologic, and entomo-virologic data gathered during 2017–2020 in Foz do Iguaçu, Brazil. We installed 3,476 adult mosquito traps across the city and inspected traps every 2 months. We compared 5 entomologic indices: traditional house and Breteau indices for larval surveys and trap positivity, adult density, and mosquitoes per inhabitant indices for adult trapping. We screened for dengue, Zika, and chikungunya viruses in live adult Aedes aegypti mosquitoes collected from traps. Indices based on adult mosquito sampling had higher outbreak predictive values than larval indices, and we were able to build choropleth maps of infestation levels

Cache Valley virus (CVV) is a mosquitoborne virus that infects livestock and humans. We report results of surveillance for CVV in New York, USA, during 2000–2016; full-genome analysis of selected CVV isolates from sheep, horse, humans, and mosquitoes from New York and Canada; and phenotypic characterization of selected strains. We calculated infection rates by using the maximum-likelihood estimation method by year, region, month, and mosquito species. The highest maximum-likelihood estimations were for Anopheles spp. mosquitoes. Our phylogenetic analysis identified 2 lineages and found evidence of segment reassortment. Furthermore, our data suggest displacement of CVV lineage 1 by lineage 2 in New York and Canada. Finally, we showed increased vector competence of An. quadrimaculatus mosquitoes for lineage 2 strains of CVV compared with lineage 1 strains.

We evaluated the effectiveness of a community-based intervention for dengue vector control in Ouagadougou, the capital city of Burkina Faso. Households in the intervention (n = 287) and control (n = 289) neighborhoods were randomly sampled and the outcomes collected before the intervention (October 2015) and after the intervention (October 2016). The intervention reduced residents' exposure to dengue vector bites (vector saliva biomarker difference -0.08 [95% CI -0.11 to -0.04]). The pupae index declined in the intervention neighborhood (from 162.14 to 99.03) and increased in the control neighborhood (from 218.72 to 255.67). Residents in the intervention neighborhood were less likely to associate dengue with malaria (risk ratio 0.70 [95% CI 0.58-0.84]) and had increased knowledge about dengue symptoms (risk ratio 1.44 [95% CI 1.22-1.69]). Our study showed that well-planned, evidence/community-based interventions that control exposure to dengue vectors are feasible and effective in urban settings in Africa that have limited resources.

Shuni virus is associated with neurologic and febrile illness in animals and humans. To determine potential vectors, we collected mosquitoes in South Africa and detected the virus in species of the genera Mansonia, Culex, Aedes, and Anopheles. These mosquitoes may be associated with Shuni virus outbreaks in Africa and emergence in other regions.

Jamestown Canyon virus (JCV) is a mosquito-borne arbovirus that circulates in North America. We detected JCV in 4 pools of mosquitoes collected from midcoastal Maine, USA, during 2017-2019. Phylogenetic analysis of a JCV sequence obtained from Aedes cantator mosquitoes clustered within clade A, which also circulates in Connecticut, USA. [ABSTRACT FROM AUTHOR]

We investigated the effects of dengue virus (DENV) on semen using samples collected 7, 15, 30, 60, and 90 days after symptom onset from 10 infected volunteers on Réunion Island. We assessed characteristics of semen and reproductive hormones and isolated motile spermatozoa from semen. We assayed semen for DENV using reverse transcription PCR and searched for DENV RNA by virus isolation in Vero E6 cell cultures. Four volunteers had >1 DENV RNA-positive semen samples; 2 volunteers had DENV RNA-positive semen at day 15 and 1 at day 30. No motile sperm were DENV positive. After exposure to positive semen, few Vero E6 cells stained positive for DENV antigens, indicating low levels of replicative virus. We found DENV had shorter duration in semen than in blood. These findings support the possibilities that DENV is sexually transmissible for a short period after acute dengue illness and that acute dengue induces reversible alterations in sperm. [ABSTRACT FROM AUTHOR]

In China, the prevention and control of Zika virus disease has been a public health threat since the first imported case was reported in February 2016. To determine the vector competence of potential vector mosquito species, we experimentally infected Aedes aegypti, Ae. albopictus, and Culex quinquefasciatus mosquitoes and determined infection rates, dissemination rates, and transmission rates. We found the highest vector competence for the imported Zika virus in Ae. aegypti mosquitoes, some susceptibility of Ae. albopictus mosquitoes, but no transmission ability for Cx. quinquefasciatus mosquitoes. Considering that, in China, Ae. albopictus mosquitoes are widely distributed but Ae. aegypti mosquito distribution is limited, Ae. albopictus mosquitoes are a potential primary vector for Zika virus and should be targeted in vector control strategies.

A new Getah virus (GETV) strain, B254, was isolated from Culex fuscocephalus mosquitoes captured at Mount Ophir, Malaysia, in 2012. Phylogenetic analyses revealed that GETV B254 is distinct from the old Malaysia GETV MM2021 strain but closely related to group IV GETV from Russia (LEIV16275Mag), China (YN12031), and Thailand (GETV/SW/Thailand/2017).

During the 2019 Eastern equine encephalitis virus (EEEV) outbreak in Michigan, two 2-month old Mexican wolf pups experienced neurologic signs, lymphohistiocytic neutrophilic meningoencephalitis with neuronal necrosis and neuronophagia, and acute death. We identified EEEV by reverse transcription real-time PCR and in situ hybridization. Vector mosquitoes were trapped at the zoo.

West Nile virus (WNV) is an emergent arthropodborne virus that is transmitted from bird to bird by mosquitoes. Spillover events occur when infected mosquitoes bite mammals. We created a geopositioned database of WNV presence in Africa and considered reports of the virus in all animal components: reservoirs, vectors, and nonhuman dead-end hosts. We built various biogeographic models to determine which drivers explain the distribution of WNV throughout Africa. Wetlands of international importance for birds accounted for the detection of WNV in all animal components, whereas human-related drivers played a key role in the epizootic cases. We combined these models to obtain an integrative and large-scale perspective of the areas at risk for WNV spillover. Understanding which areas pose the highest risk would enable us to address the management of this spreading disease and to comprehend the translocation of WNV outside Africa through avian migration routes. [ABSTRACT FROM AUTHOR]

Arbovirus epidemiology lacks efficient and timely surveillance systems with accurate outbreak alert signals. We devised a citywide integrated surveillance system combining entomologic, epidemiologic, and entomo-virologic data gathered during 2017-2020 in Foz do Iguaçu, Brazil. We installed 3,476 adult mosquito traps across the city and inspected traps every 2 months. We compared 5 entomologic indices: traditional house and Breteau indices for larval surveys and trap positivity, adult density, and mosquitoes per inhabitant indices for adult trapping. We screened for dengue, Zika, and chikungunya viruses in live adult Aedes aegypti mosquitoes collected from traps. Indices based on adult mosquito sampling had higher outbreak predictive values than larval indices, and we were able to build choropleth maps of infestation levels <36 h after each round of trap inspection. Locating naturally infected vectors provides a timely support tool for local public health managers to prioritize areas for intervention response to prevent virus outbreaks. [ABSTRACT FROM AUTHOR]

Anopheles stephensi mosquitoes, efficient vectors in parts of Asia and Africa, were found in 75.3% of water sources surveyed and contributed to 80.9% of wild-caught Anopheles mosquitoes in Awash Sebat Kilo, Ethiopia. High susceptibility of these mosquitoes to Plasmodium falciparum and vivax infection presents a challenge for malaria control in the Horn of Africa.

Cache Valley virus (CVV) is a mosquitoborne virus that infects livestock and humans. We report results of surveillance for CVV in New York, USA, during 2000-2016; full-genome analysis of selected CVV isolates from sheep, horse, humans, and mosquitoes from New York and Canada; and phenotypic characterization of selected strains. We calculated infection rates by using the maximum-likelihood estimation method by year, region, month, and mosquito species. The highest maximum-likelihood estimations were for Anopheles spp. mosquitoes. Our phylogenetic analysis identified 2 lineages and found evidence of segment reassortment. Furthermore, our data suggest displacement of CVV lineage 1 by lineage 2 in New York and Canada. Finally, we showed increased vector competence of An. quadrimaculatus mosquitoes for lineage 2 strains of CVV compared with lineage 1 strains. [ABSTRACT FROM AUTHOR]

We detected Rift Valley fever virus (RVFV) IgM and IgG in human serum samples collected during 2018-2019 in northern KwaZulu-Natal Province, South Africa. Our results show recent RVFV circulation and likely RVFV endemicity in this tropical coastal plain region of South Africa in the absence of apparent clinical disease. [ABSTRACT FROM AUTHOR]

Shuni virus is associated with neurologic and febrile illness in animals and humans. To determine potential vectors, we collected mosquitoes in South Africa and detected the virus in species of the genera Mansonia, Culex, Aedes, and Anopheles. These mosquitoes may be associated with Shuni virus outbreaks in Africa and emergence in other regions. [ABSTRACT FROM AUTHOR]

In 2016, four clusters of local mosquitoborne Zika virus transmission were identified in Miami-Dade County, Florida, USA, generating “red zones” (areas into which pregnant women were advised against traveling). The Miami-Dade County Mosquito Control Division initiated intensive control activities, including property inspections, community education, and handheld sprayer applications of larvicides and adulticides. For the first time, the Mosquito Control Division used a combination of areawide ultralow-volume adulticide and low-volume larvicide spraying to effectively control Aedes aegypti mosquitoes, the primary Zika virus vector within the county. The number of mosquitoes rapidly decreased, and Zika virus transmission was interrupted within the red zones immediately after the combination of adulticide and larvicide spraying.

Australia experienced its largest recorded outbreak of Ross River virus (RRV) during the 2014–15 reporting year, comprising >10,000 reported cases. We investigated epidemiologic, entomologic, and virologic factors that potentially contributed to the scale of the outbreak in Queensland, the state with the highest number of notifications (6,371). Spatial analysis of human cases showed that notifications were geographically widespread. In Brisbane, human case notifications and virus detections in mosquitoes occurred across inland and coastal locations. Viral sequence data demonstrated 2 RRV lineages (northeastern genotypes I and II) were circulating, and a new strain containing 3 unique amino acid changes in the envelope 2 protein was identified. Longitudinal mosquito collections demonstrated unusually high relative abundance of Culex annulirostris and Aedes procax mosquitoes, attributable to extensive freshwater larval habitats caused by early and persistent rainfall during the reporting year. Increased prevalence of these mosquitoes probably contributed to the scale of this outbreak.

Zika virus infection (ZIKV), transmitted primarily by the Aedes aegypti and Ae. albopictus mosquitoes, is a serious threat to pregnant women because of the risk of microcephaly and other birth [...]

West Nile virus (WNV), the causative agent of West Nile fever (WNF), is an arbovirus of the genus Flavivirus, family Flaviviridae. WNV has been reported in a variety of species [...]

The southwestern islands of the Indian Ocean are threatened by arbovirus outbreaks because of their tropical climate, geographic proximity to arbovirus-endemic countries, tourism, and numerous commercial exchanges. One such island [...]

We detected 2 natural, asymptomatic Plasmodium inui monoinfections in humans in Malaysia by using nested PCR on concentrated high-volume blood samples. We found a P. inui-positive Anopheles cracens mosquito in the same site as the human infections. Investigators should use ultrasensitive detection methods to identify simian malaria parasite transmission in humans. [ABSTRACT FROM AUTHOR]

Among 713 equids sampled in northeastern Brazil during 2013-2018, West Nile virus seroprevalence was 4.5% (95% CI 3.1%-6.3%). Mathematical modeling substantiated higher seroprevalence adjacent to an avian migratory route and in areas characterized by forest loss, implying increased risk for zoonotic infections in disturbed areas. [ABSTRACT FROM AUTHOR]

Anopheles stephensi mosquitoes share urban breeding sites with Aedes aegypti and Culex quinquefasciatus mosquitoes in the Republic of Djibouti. We present evidence that A. stephensi mosquitoes might be responsible for an increase in malaria incidence in this country. We also document resistance of Plasmodium falciparum to dihydroartemisinin/piperaquine. [ABSTRACT FROM AUTHOR]

Zika virus infection during pregnancy can cause brain abnormalities, microcephaly, and other birth defects in exposed offspring (1,2). Although transmission of Zika virus primarily occurs through the bite of an [...]

Yellow fever virus (family Flaviviridae, genus Flavivirus) is spread by bites of infected mosquitoes of the genera Aedes, Haemagogus, and Sabethes (1). During 2017, an epidemic of yellow fever in [...]

Japanese encephalitis is a mosquitoborne zoonotic viral disease caused by Japanese encephalitis virus (JEV; family Flaviviridae, genus Flavivirus). The virus genome contains a 5' untranslated region (UTR), followed by a [...]

Zika virus is an enveloped, positive-sense, single-stranded sRNA, arthropod-borne virus (arbovirus) that is classified in the genus Flavivirus, family Flaviviridae. Zika virus is closely related to other viruses of medical [...]

Many sectors of society have taken full advantage of new opportunities provided by big data, but public health has not (1). Although electronic health records have long been used in [...]

Plasmodium knowlesi is a simian malaria parasite and is recognized as the fifth human malaria parasite (1). Natural infection in humans by P. knowlesi was first reported in Malaysian Borneo [...]

In Africa, the prevalence of disease caused by Aedes mosquito-borne virus infections might be similar to that in the Americas (1,2). However, the transmission and genetic diversity of arthropodborne viruses [...]

Malaria is one of the major reasons for seeking healthcare in public health facilities in Mauritania. In 2016, among an estimated population of 3,537,368, malaria incidence was 78/1,000 persons at [...]

The genus Elizabethkingia comprises glucose-nonfermenting, gram-negative rods that are widely distributed in natural environments, including in soil and freshwater, and in hospital environments (1). E. meningoseptica (originally named Chryseobacterium meningoseptica) [...]

Evidence suggests that pigs seroconvert after experimental exposure to Zika virus and are potential sentinels. We demonstrate that pigs are also susceptible to natural Zika virus infection, shown by the presence of antibodies in domestic pigs in Yucatan, Mexico. Zika virus RNA was detected in 5 species of mosquitoes collected inside pigpens. [ABSTRACT FROM AUTHOR]

Anopheles stephensi mosquitoes, efficient vectors in parts of Asia and Africa, were found in 75.3% of water sources surveyed and contributed to 80.9% of wild-caught Anopheles mosquitoes in Awash Sebat Kilo, Ethiopia. High susceptibility of these mosquitoes to Plasmodium falciparum and vivax infection presents a challenge for malaria control in the Horn of Africa. [ABSTRACT FROM AUTHOR]