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2.
Parasit Vectors ; 17(1): 204, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38715075

RESUMEN

BACKGROUND: Mosquito-borne viruses cause various infectious diseases in humans and animals. Oya virus (OYAV) and Ebinur Lake virus (EBIV), belonging to the genus Orthobunyavirus within the family Peribunyaviridae, are recognized as neglected viruses with the potential to pose threats to animal or public health. The evaluation of vector competence is essential for predicting the arbovirus transmission risk. METHODS: To investigate the range of mosquito vectors for OYAV (strain SZC50) and EBIV (strain Cu20-XJ), the susceptibility of four mosquito species (Culex pipiens pallens, Cx. quinquefasciatus, Aedes albopictus, and Ae. aegypti) was measured through artificial oral infection. Then, mosquito species with a high infection rate (IR) were chosen to further evaluate the dissemination rate (DR), transmission rate (TR), and transmission efficiency. The viral RNA in each mosquito sample was determined by RT-qPCR. RESULTS: The results revealed that for OYAV, Cx. pipiens pallens had the highest IR (up to 40.0%) among the four species, but the DR and TR were 4.8% and 0.0%, respectively. For EBIV, Cx. pipiens pallens and Cx. quinquefasciatus had higher IR compared to Ae. albopictus (1.7%). However, the EBIV RNA and infectious virus were detected in Cx. pipiens pallens, with a TR of up to 15.4% and a transmission efficiency of 3.3%. CONCLUSIONS: The findings indicate that Cx. pipiens pallens was susceptible to OYAV but had an extremely low risk of transmitting the virus. Culex pipiens pallens and Cx. quinquefasciatus were susceptible to EBIV, and Cx. pipiens pallens had a higher transmission risk to EBIV than Cx. quinquefasciatus.


Asunto(s)
Aedes , Culex , Mosquitos Vectores , Orthobunyavirus , Animales , Mosquitos Vectores/virología , Aedes/virología , Culex/virología , Orthobunyavirus/genética , Orthobunyavirus/clasificación , Orthobunyavirus/aislamiento & purificación , ARN Viral/genética , Infecciones por Bunyaviridae/transmisión , Infecciones por Bunyaviridae/virología
3.
Parasit Vectors ; 17(1): 223, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750581

RESUMEN

BACKGROUND: Batai virus (BATV) is a zoonotic arbovirus of veterinary importance. A high seroprevalence in cows, sheep and goats and infection in different mosquito species has been observed in Central Europe. Therefore, we studied indigenous as well as exotic species of the genera Culex and Aedes for BATV vector competence at different fluctuating temperature profiles. METHODS: Field caught Culex pipiens biotype pipiens, Culex torrentium, Aedes albopictus and Aedes japonicus japonicus from Germany and Aedes aegypti laboratory colony were infected with BATV strain 53.3 using artificial blood meals. Engorged mosquitoes were kept under four (Culex species) or three (Aedes species) fluctuating temperature profiles (18 ± 5 °C, 21 ± 5 °C, 24 ± 5 °C, 27 ± 5 °C) at a humidity of 70% and a dark/light rhythm of 12:12 for 14 days. Transmission was measured by testing the saliva obtained by forced salivation assay for viable BATV particles. Infection rates were analysed by testing whole mosquitoes for BATV RNA by quantitative reverse transcription PCR. RESULTS: No transmission was detected for Ae. aegypti, Ae. albopictus or Ae. japonicus japonicus. Infection was observed for Cx. p. pipiens, but only in the three conditions with the highest temperatures (21 ± 5 °C, 24 ± 5 °C, 27 ± 5 °C). In Cx. torrentium infection was measured at all tested temperatures with higher infection rates compared with Cx. p. pipiens. Transmission was only detected for Cx. torrentium exclusively at the highest temperature of 27 ± 5 °C. CONCLUSIONS: Within the tested mosquito species, only Cx. torrentium seems to be able to transmit BATV if the climatic conditions are feasible.


Asunto(s)
Aedes , Virus Bunyamwera , Culex , Mosquitos Vectores , Temperatura , Animales , Aedes/virología , Aedes/fisiología , Aedes/clasificación , Culex/virología , Culex/fisiología , Culex/clasificación , Mosquitos Vectores/virología , Mosquitos Vectores/fisiología , Virus Bunyamwera/genética , Virus Bunyamwera/fisiología , Virus Bunyamwera/aislamiento & purificación , Saliva/virología , Infecciones por Bunyaviridae/transmisión , Infecciones por Bunyaviridae/virología , Femenino , Europa (Continente) , Alemania
4.
Lancet Infect Dis ; 24(7): e439-e452, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38281494

RESUMEN

Since its discovery in 1955, the incidence and geographical spread of reported Oropouche virus (OROV) infections have increased. Oropouche fever has been suggested to be one of the most important vector-borne diseases in Latin America. However, both literature on OROV and genomic sequence availability are scarce, with few contributing laboratories worldwide. Three reassortant OROV glycoprotein gene variants termed Iquitos, Madre de Dios, and Perdões virus have been described from humans and non-human primates. OROV predominantly causes acute febrile illness, but severe neurological disease such as meningoencephalitis can occur. Due to unspecific symptoms, laboratory diagnostics are crucial. Several laboratory tests have been developed but robust commercial tests are hardly available. Although OROV is mainly transmitted by biting midges, it has also been detected in several mosquito species and a wide range of vertebrate hosts, which likely facilitates its widespread emergence. However, potential non-human vertebrate reservoirs have not been systematically studied. Robust animal models to investigate pathogenesis and immune responses are not available. Epidemiology, pathogenesis, transmission cycle, cross-protection from infections with OROV reassortants, and the natural history of infection remain unclear. This Review identifies Oropouche fever as a neglected disease and offers recommendations to address existing knowledge gaps, enable risk assessments, and ensure effective public health responses.


Asunto(s)
Infecciones por Bunyaviridae , Humanos , Animales , América Latina/epidemiología , Infecciones por Bunyaviridae/epidemiología , Infecciones por Bunyaviridae/transmisión , Infecciones por Bunyaviridae/diagnóstico , Infecciones por Bunyaviridae/virología , Orthobunyavirus/genética , Orthobunyavirus/patogenicidad , Orthobunyavirus/aislamiento & purificación , Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Transmisibles Emergentes/virología
5.
Transbound Emerg Dis ; 69(4): e153-e160, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34343411

RESUMEN

Schmallenberg orthobunyavirus (SBV) was initially detected in 2011 in Germany from dairy cattle with fever and decreased milk yield. The virus infection is now established in many parts of the world with recurrent epidemics. SBV is transmitted through midges and transplacental. No direct virus transmission including via breeding has ever been demonstrated. In some bulls, however, the virus is detectable transiently, in low to minute quantities, in semen post-infection. While the infection is considered of low impact for the dairy industry, some SBV-free countries have adopted a zero-risk approach requiring bull semen batches to be tested for SBV RNA residues prior to import. This, in turn, obligates a protocol to enable sensitive detection of SBV RNA in semen samples for export purposes. Here, we describe how we established a now ISO/IEC 17025 accredited protocol that can effectively detect minute quantities of SBV RNA in semen and also its application to monitor bull semen during two outbreaks in the United Kingdom in 2012 and 2016. The data demonstrate that only a small number of bulls temporarily shed low amounts of SBV.


Asunto(s)
Crianza de Animales Domésticos , Infecciones por Bunyaviridae , Enfermedades de los Bovinos , Orthobunyavirus , Semen , Crianza de Animales Domésticos/métodos , Animales , Infecciones por Bunyaviridae/diagnóstico , Infecciones por Bunyaviridae/prevención & control , Infecciones por Bunyaviridae/transmisión , Infecciones por Bunyaviridae/veterinaria , Bovinos , Enfermedades de los Bovinos/diagnóstico , Enfermedades de los Bovinos/prevención & control , Enfermedades de los Bovinos/transmisión , Masculino , Orthobunyavirus/genética , ARN Viral/genética , Semen/virología , Sensibilidad y Especificidad
6.
Parasit Vectors ; 14(1): 566, 2021 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-34732254

RESUMEN

BACKGROUND: A number of zoonotic mosquito-borne viruses have emerged in Europe in recent decades. Batai virus (BATV), a member of the genus Orthobunyavirus, is one example of a relatively newly emerged mosquito-borne virus, having been detected in mosquitoes and livestock. We conducted vector competency studies on three mosquito species at a low temperature to assess whether Aedes and Culex mosquito species are susceptible to infection with BATV. METHODS: Colonised lines of Aedes aegypti and Culex pipiens and a wild-caught species, Aedes detritus, were orally inoculated with BATV strain 53.2, originally isolated from mosquitoes trapped in Germany in 2009. Groups of blood-fed female mosquitoes were maintained at 20 °C for 7 or 14 days. Individual mosquitoes were screened for the presence of BATV in body, leg and saliva samples for evidence of infection, dissemination and transmission, respectively. BATV RNA was detected by reverse transcription-PCR, and positive results confirmed by virus isolation in Vero cells. RESULTS: Aedes detritus was highly susceptible to BATV, with an infection prevalence of ≥ 80% at both measurement time points. Disseminated infections were recorded in 30.7-41.6% of Ae. detritus, and evidence of virus transmission with BATV in saliva samples (n = 1, days post-infection: 14) was observed. Relatively lower rates of infection for Ae. aegypti and Cx. pipiens were observed, with no evidence of virus dissemination or transmission at either time point. CONCLUSIONS: This study shows that Ae. detritus may be a competent vector for BATV at 20 °C, whereas Ae. aegypti and Cx. pipiens were not competent. Critically, the extrinsic incubation period appears to be ≤ 7 days for Ae. detritus, which may increase the onward transmissibility potential of BATV in these populations.


Asunto(s)
Virus Bunyamwera/fisiología , Culicidae/virología , Mosquitos Vectores/virología , Animales , Virus Bunyamwera/genética , Infecciones por Bunyaviridae/transmisión , Infecciones por Bunyaviridae/virología , Culicidae/inmunología , Europa (Continente) , Femenino , Humanos , Masculino , Mosquitos Vectores/inmunología , Saliva/virología
7.
Viruses ; 13(11)2021 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-34834956

RESUMEN

Important lessons have been learned by the Israeli veterinary community regarding Simbu serogroup viruses infections. This serogroup of viruses might cause the births of neonatal malformation in susceptible ruminant's populations. Until 2012, only Akabane virus was connected with the births of malformed ruminants in Israel. However, serological and genomic detection tests, coupled with viral isolations, revealed that more than a single Simbu serogroup serotype could be present concurrently in the same farm or even in the same animal. From 2012 to date, Aino, Shuni, Shamunda, Satuperi, Peaton, Schmallenberg, and Sango viruses have been found in Israel either by serological or genomic investigation. Israel is located in the Eastern Mediterranean Basin, a terrestrial and climatic bridge between the three old continents. The Eastern Mediterranean shores benefit from both the tropical/subtropical and the continental climatic conditions. Therefore, the Eastern Mediterranean basin might serve as an optimal investigatory compound for several arboviral diseases, acting as a sentinel. This review summarizes updated information related to the presence of Simbu serogroup viruses in Israel.


Asunto(s)
Infecciones por Bunyaviridae/transmisión , Infecciones por Bunyaviridae/virología , Clima , Ganado/virología , Virus Simbu , Animales , Infecciones por Arbovirus/epidemiología , Infecciones por Arbovirus/transmisión , Infecciones por Arbovirus/virología , Infecciones por Bunyaviridae/epidemiología , Bovinos , Enfermedades de los Bovinos/virología , Enfermedades Transmisibles Emergentes , Brotes de Enfermedades/veterinaria , Israel , Orthobunyavirus , Rumiantes/virología , Serogrupo , Ovinos , Enfermedades de las Ovejas/virología , Virus Simbu/clasificación , Virus Simbu/genética , Virus Simbu/aislamiento & purificación
8.
Parasit Vectors ; 14(1): 561, 2021 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-34717742

RESUMEN

BACKGROUND: Tahyna orthobunyavirus (TAHV) is a mosquito-borne virus that may cause mild flu-like symptoms or neurological symptoms in humans. It is historically associated with floodplain habitats in Central Europe, and the mammalophilic floodwater mosquito, Aedes vexans, is thought to be the principal vector. There are few contemporary reports of TAHV transmission ecology within mosquitoes or their vertebrate hosts, and virus infections are rarely reported (and probably seldom diagnosed). The objectives of this study were to survey the mosquito population for TAHV in three floodwater habitats and describe host usage by the predominant floodwater mosquito species to potentially define TAHV transmission at these foci. METHODS: We performed longitudinal mosquito sampling along three major rivers in eastern Austria to characterize the mosquito community in floodplain habitats, and tested for the presence of TAHV in pools of mosquitoes. We characterized TAHV rescued from mosquito pool homogenate by sequencing. We surveyed mosquito host selection by analyzing mosquito blood meals. RESULTS: We identified TAHV in two pools of Ae. vexans captured along the Leitha River. This mosquito, and other floodwater mosquitoes, used large mammals (red deer, roe deer, wild boar) as their hosts. The sequence of the rescued virus was remarkably similar to other TAHV isolates from the region, dating back to the first isolate of TAHV in 1958. CONCLUSIONS: In general, we confirmed that TAHV is most likely being transmitted by Ae. vexans, although the precise contribution of vertebrate-amplifying hosts to the ecological maintenance of the virus is unclear. The pattern of host selection matches the estimated exposure of the same large mammal species in the region to TAHV based on a recent serosurvey, but hares were also hosts at the site where TAHV was detected. We also confirm humans as hosts of two floodwater mosquito species, providing a potential mechanism for spillover of TAHV or other mosquito-borne viruses.


Asunto(s)
Aedes/virología , Infecciones por Bunyaviridae/transmisión , Ecosistema , Mosquitos Vectores/virología , Orthobunyavirus/genética , Orthobunyavirus/fisiología , Aedes/genética , Animales , Austria , Sangre , Infecciones por Bunyaviridae/virología , Femenino , Humanos , Estudios Longitudinales , Comidas , Mosquitos Vectores/genética , Orthobunyavirus/clasificación
9.
Emerg Microbes Infect ; 10(1): 1649-1659, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34353229

RESUMEN

Cache Valley virus (CVV) is a prevalent emerging pathogen of significant importance to agricultural and human health in North America. Emergence in livestock can result in substantial agroeconomic losses resulting from the severe embryonic lethality associated with infection during pregnancy. Although CVV pathogenesis has been well described in ruminants, small animal models are still unavailable, which limits our ability to study its pathogenesis and perform preclinical testing of therapeutics. Herein, we explored CVV pathogenesis, tissue tropism, and disease outcomes in a variety of murine models, including immune -competent and -compromised animals. Our results show that development of CVV disease in mice is dependent on innate immune responses, and type I interferon signalling is essential for preventing infection in mice. IFN-αßR-/- mice infected with CVV present with significant disease and lethal infections, with minimal differences in age-dependent pathogenesis, suggesting this model is appropriate for pathogenesis-related, and short- and long-term therapeutic studies. We also developed a novel CVV in utero transmission model that showed high rates of transmission, spontaneous abortions, and congenital malformations during infection. CVV infection presents a wide tissue tropism, with significant amplification in liver, spleen, and placenta tissues. Immune-competent mice are generally resistant to infection, and only show disease in an age dependent manner. Given the high seropositivity rates in regions of North America, and the continuing geographic expansion of competent mosquito vectors, the risk of epidemic and epizootic emergence of CVV is high, and interventions are needed for this important pathogen.


Asunto(s)
Virus Bunyamwera/patogenicidad , Infecciones por Bunyaviridae/transmisión , Infecciones por Bunyaviridae/virología , Modelos Animales de Enfermedad , Transmisión Vertical de Enfermedad Infecciosa , Ratones , Animales , Femenino , Mosquitos Vectores/virología , Embarazo
10.
Viruses ; 13(5)2021 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-33923055

RESUMEN

The emergence of new human viral pathogens and re-emergence of several diseases are of particular concern in the last decades. Oropouche orthobunyavirus (OROV) is an arbovirus endemic to South and Central America tropical regions, responsible to several epidemic events in the last decades. There is little information regarding the ability of OROV to be transmitted by urban/peri-urban mosquitoes, which has limited the predictability of the emergence of permanent urban transmission cycles. Here, we evaluated the ability of OROV to infect, replicate, and be transmitted by three anthropophilic and urban species of mosquitoes, Aedes aegypti, Aedes albopictus, and Culex quinquefasciatus. We show that OROV is able to infect and efficiently replicate when systemically injected in all three species tested, but not when orally ingested. Moreover, we find that, once OROV replication has occurred in the mosquito body, all three species were able to transmit the virus to immunocompromised mice during blood feeding. These data provide evidence that OROV is restricted by the midgut barrier of three major urban mosquito species, but, if this restriction is overcome, could be efficiently transmitted to vertebrate hosts. This poses a great risk for the emergence of permanent urban cycles and geographic expansion of OROV to other continents.


Asunto(s)
Aedes/virología , Culex/virología , Mosquitos Vectores/virología , Orthobunyavirus/fisiología , Animales , Infecciones por Bunyaviridae/transmisión , Infecciones por Bunyaviridae/virología , Modelos Animales de Enfermedad , Femenino , Especificidad del Huésped , Interacciones Huésped-Patógeno , Ratones , Ratones Noqueados
11.
Viruses ; 13(2)2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33540546

RESUMEN

Oropouche virus (OROV), a vector-borne Orthobunyavirus circulating in South and Central America, causes a febrile illness with high rates of morbidity but with no documented fatalities. Oropouche virus is transmitted by numerous vectors, including multiple genera of mosquitoes and Culicoides biting midges in South America. This study investigated the vector competence of three North American vectors, Culex tarsalis, Culex quinquefasciatus, and Culicoides sonorensis, for OROV. Cohorts of each species were fed an infectious blood meal containing 6.5 log10 PFU/mL OROV and incubated for 10 or 14 days. Culex tarsalis demonstrated infection (3.13%) but not dissemination or transmission potential at 10 days post infection (DPI). At 10 and 14 DPI, Cx. quinquefasciatus demonstrated 9.71% and 19.3% infection, 2.91% and 1.23% dissemination, and 0.97% and 0.82% transmission potential, respectively. Culicoides sonorensis demonstrated 86.63% infection, 83.14% dissemination, and 19.77% transmission potential at 14 DPI. Based on these data, Cx. tarsalis is unlikely to be a competent vector for OROV. Culex quinquefasciatus demonstrated infection, dissemination, and transmission potential, although at relatively low rates. Culicoides sonorensis demonstrated high infection and dissemination but may have a salivary gland barrier to the virus. These data have implications for the spread of OROV in the event of a North American introduction.


Asunto(s)
Infecciones por Bunyaviridae/transmisión , Ceratopogonidae/virología , Culex/virología , Mosquitos Vectores/virología , Animales , Orthobunyavirus/fisiología , Estados Unidos , Enfermedades Transmitidas por Vectores/transmisión , Enfermedades Transmitidas por Vectores/virología
12.
Parasit Vectors ; 14(1): 93, 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33536057

RESUMEN

BACKGROUND: In the last two decades, recurrent epizootics of bluetongue virus and Schmallenberg virus have been reported in the western Palearctic region. These viruses affect domestic cattle, sheep, goats and wild ruminants and are transmitted by native hematophagous midges of the genus Culicoides (Diptera: Ceratopogonidae). Culicoides dispersal is known to be stratified, i.e. due to a combination of dispersal processes occurring actively at short distances and passively or semi-actively at long distances, allowing individuals to jump hundreds of kilometers. METHODS: Here, we aim to identify the environmental factors that promote or limit gene flow of Culicoides obsoletus, an abundant and widespread vector species in Europe, using an innovative framework integrating spatial, population genetics and statistical approaches. A total of 348 individuals were sampled in 46 sites in France and were genotyped using 13 newly designed microsatellite markers. RESULTS: We found low genetic differentiation and a weak population structure for C. obsoletus across the country. Using three complementary inter-individual genetic distances, we did not detect any significant isolation by distance, but did detect significant anisotropic isolation by distance on a north-south axis. We employed a multiple regression on distance matrices approach to investigate the correlation between genetic and environmental distances. Among all the environmental factors that were tested, only cattle density seems to have an impact on C. obsoletus gene flow. CONCLUSIONS: The high dispersal capacity of C. obsoletus over land found in the present study calls for a re-evaluation of the impact of Culicoides on virus dispersal, and highlights the urgent need to better integrate molecular, spatial and statistical information to guide vector-borne disease control.


Asunto(s)
Lengua Azul/transmisión , Infecciones por Bunyaviridae/transmisión , Ceratopogonidae/genética , Ceratopogonidae/virología , Ambiente , Insectos Vectores/virología , Animales , Virus de la Lengua Azul/fisiología , Bovinos/parasitología , Ceratopogonidae/fisiología , Europa (Continente) , Conducta Alimentaria , Femenino , Francia , Flujo Génico , Genotipo , Insectos Vectores/fisiología , Repeticiones de Microsatélite , Orthobunyavirus/fisiología , Dinámica Poblacional , Estaciones del Año
13.
Acta Trop ; 214: 105790, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33309594

RESUMEN

Ngari virus is a mosquito-borne virus belonging to the genus Orthobunyavirus (Peribunyaviridae family). This virus is pathogenic to humans and causes severe illness. Ngari virus is present in several African countries, including Madagascar. Here, we report the detection of Ngari virus in ixodid ticks collected from cows in Guinea. A tick survey was conducted in March-November of 2018 in six regions of Guinea. The sample comprised 710 pools, with a total of 2067 ticks belonging to five species collected from 197 cows. At the initial stage, we screened a subsample of tick pools of vector-borne viruses with a multiplex genus-specific primer panel. In the second stage of the study, we narrowed the search and screened all the samples by qPCR for the detection of Ngari virus. All positive samples were sequenced with primers flanking Ngari virus-specific fragments on the S and M segments. We found Ngari virus in 12 pools that were formed from engorged ticks collected from livestock in three villages of the Kindia and Kankan regions. Sequencing of the S and M segments confirmed that the detected viruses belong to Ngari virus, and the viruses were most similar to the strain Adrar, which was isolated in Mauritania. We detected viral RNA in ticks of the following species: Amblyomma variegatum, Rhipicephalus geigyi, and Rh. (Boophilus) spp. There is no evidence that ixodid ticks are competent vectors of the Ngari virus. Most likely, the ticks obtained the virus through blood from an infected host. The study of engorged ticks can be recommended as a simpler approach for the wide screening of the Ngari virus and subsequent testing of cattle and mosquitos in those locations where the PCR-positive ticks were collected.


Asunto(s)
Infecciones por Bunyaviridae/veterinaria , Enfermedades de los Bovinos/epidemiología , Ixodidae/virología , Orthobunyavirus/aislamiento & purificación , Infestaciones por Garrapatas/veterinaria , Animales , Infecciones por Bunyaviridae/epidemiología , Infecciones por Bunyaviridae/transmisión , Bovinos , Enfermedades de los Bovinos/parasitología , Enfermedades de los Bovinos/transmisión , Enfermedades de los Bovinos/virología , Femenino , Guinea/epidemiología , Humanos , Orthobunyavirus/genética , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/parasitología
14.
J Med Entomol ; 58(3): 1384-1388, 2021 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-33210706

RESUMEN

We evaluated the potential for mosquitoes collected in the Amazon Basin, near Iquitos, Peru, to become infected with and transmit Murutucu (MURV) and Itaqui viruses (ITQV) (Order Bunyavirales, Family: Peribunyaviridae, Genus: Orthobunyavirus). Viremia levels in Syrian hamsters peaked 2 d after infection with either virus, and both viruses were highly lethal in hamsters with virtually all hamsters dying prior to 3-d postinfection. For almost all of the mosquito species tested some individuals were susceptible to infection and some developed a disseminated infection after oral exposure to either MURV or ITQV. However, only the Culex species (Culex (Culex) coronator Dyar and Knab [Diptera, Culicidae], Culex (Melanoconian) gnomatos Sallum, Huchings, and Ferreira [Diptera, Culicidae], Culex (Mel.) pedroi Sirivanakarn and Belkin [Diptera, Culicidae], and Culex (Mel.) vomerifer Komp [Diptera, Culicidae]) successfully transmitted virus by bite. However, even among these species, only about 37% of the individuals with a disseminated infection successfully transmitted these viruses, indicating a significant salivary gland barrier. Although little is known about the medical or veterinary importance of many members of the genus Orthobunyavirus, we have demonstrated that Culex spp. (Diptera, Culicidae) could be potential vectors.


Asunto(s)
Infecciones por Bunyaviridae/transmisión , Culicidae/virología , Mosquitos Vectores/virología , Orthobunyavirus/aislamiento & purificación , Animales , Femenino , Mesocricetus , Perú
15.
J Clin Virol ; 128: 104452, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32474372

RESUMEN

BACKGROUND: Toscana virus (TOSV) is a Phlebovirus transmitted to humans by phlebotomines and represent an etiological agent of acute aseptic meningitis (AAM) in countries where the virus is endemic, including Italy. Incidence of TOSV infections is closely associated with the geographical distribution of the phlebotomine vectors which in turn is affected by climate changes that determine survival and spread. As a result, TOSV infections show a seasonal trend with a peak of incidence in summer months. OBJECTIVES: To measure the prevalence of TOSV infections in AAM patients in central Italy and evaluate the climate changes in phlebotomine vectors ecology and virus propagation. STUDY DESIGN: One thousand and seventy-three cerebrospinal fluid samples (CSFs), collected from patients with suspected viral meningitis, were collected over nine years (2011-2019) during the May to October period and tested for viruses most commonly associated with AAM. Serum samples addressed to the Microbiology and Virology Unit of "S. Maria delle Scotte" Hospital for confirmation acute TOSV infection (n = 324) were tested for TOSV-specific IgM and IgG. RESULTS: Among the CSF samples, 1.3% were positive for Enteroviruses; 0.9% for Varicella zoster virus, 1.9% for Herpes simplex virus type-1/2 and 4.6% for TOSV. Serum IgM analyses disclosed TOSV-specific IgM in 27.1% of sera suggesting the predominant involvement of TOSV in neuroinvasive infections. CONCLUSIONS: This data confirms the predominant role of TOSV as causative agent of AAM during the summer time in endemic countries. Moreover, climate changes affecting phlebotomine vectors persistence, reproduction and activity could be involved in the cyclic nature of TOSV infection reported during the last nine years.


Asunto(s)
Anticuerpos Antivirales/sangre , Infecciones por Bunyaviridae/epidemiología , Infecciones por Bunyaviridae/transmisión , Meningitis Viral/epidemiología , Virus de Nápoles de la Fiebre de la Mosca de los Arenales/patogenicidad , Adolescente , Adulto , Factores de Edad , Femenino , Geografía , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Italia/epidemiología , Masculino , Persona de Mediana Edad , Virus de Nápoles de la Fiebre de la Mosca de los Arenales/inmunología , Factores Sexuales , Adulto Joven
16.
PLoS Negl Trop Dis ; 14(6): e0008368, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32520966

RESUMEN

Severe fever with thrombocytopenia syndrome virus (SFTSV) is a novel phlebovirus in the Bunyaviridae family, causing SFTS with high mortality rate. Haemaphysalis longicornis ticks has been demonstrated as a competent vector of SFTSV by experimental transmission study and field study. However, there has been query whether other tick species that infest human beings in the SFTS endemic regions are capable of transmitting the pathogen. Here by performing experimental transmission study, we compared the capable of transmitting SFTSV among Ixodes sinensis, Ixodes persulcatus and Dermacentor silvarum ticks. The transovarial transmission was seen in the I. sinensis ticks with a rate of 40%, but neither in I. persulcatus nor in D. silvarum ticks. I. sinensis ticks also have the ability to transmit SFTSV horizontally to uninfected mice at 7 days after feeding, but not for I. persalcatus or D. silvarum ticks. In the transstadial transmission of I. persulcatus and D. silvarum ticks, I. persulcatus ticks were tested negative from larvae to adults. But the D. silvarum ticks were tested positive from larvae to nymphs, with the positive rate of 100% (10/10) for engorged larval ticks and 81.25% (13/16) for molted nymphs. However, the mice bitten by SFTSV-infected D. silvarum nymphs were negative for SFTSV detection. Therefore, there is not enough evidence to prove the transstadial transmission of SFTSV in I. persalcatus and D. silvarum ticks.


Asunto(s)
Vectores Arácnidos/virología , Infecciones por Bunyaviridae/transmisión , Infecciones por Bunyaviridae/virología , Transmisión de Enfermedad Infecciosa/veterinaria , Ixodidae/virología , Phlebovirus/fisiología , Animales , Femenino , Humanos , Ixodes/virología , Ixodidae/clasificación , Larva/virología , Ratones , Ninfa , Conejos
17.
Med Vet Entomol ; 34(4): 402-410, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32426867

RESUMEN

Toscana virus (TOSV) is a prominent arthropod-borne viral agent of human central nervous system infections occurring in the Mediterranean region. The main transmission route to susceptible individuals involves sandflies as vectors. Despite several reports revealing widespread TOSV activity in Turkey, vectors remained unidentified. A sandfly field survey was carried out in five provinces in Central, Southeast and Mediterranean Anatolia in 2017 to identify TOSV and related sandfly-borne phleboviruses and Leishmania parasites, with evidence for circulation in the region. A total of 7136 sandfly specimens, collected via standard methods, were evaluated in 163 pools. TOSV was detected in 11 pools (6.7%), comprising Phlebotomus major sensu lato, Sergentomyia dentata and Phlebotomus papatasi species. TOSV partial L and S segment sequences were characterized, that phylogenetically clustered with local and global genotype A strains. An amino acid substitution outside the conserved motifs of the viral polymerase, also present in previous TOSV sequences in endemic regions, was observed. Leishmania tropica was detected in a single pool of Ph. sergentii (0.6%). This is the first report of TOSV in sandflies from Turkey, and this study further provides evidence for additional sandfly species with the potential to transmit TOSV.


Asunto(s)
Phlebotomus , Virus de Nápoles de la Fiebre de la Mosca de los Arenales , Animales , Infecciones por Bunyaviridae/transmisión , Humanos , Insectos Vectores/parasitología , Insectos Vectores/virología , Leishmania tropica/aislamiento & purificación , Leishmaniasis Cutánea/transmisión , Phlebotomus/clasificación , Phlebotomus/parasitología , Phlebotomus/virología , Filogenia , Psychodidae/clasificación , Psychodidae/parasitología , Psychodidae/virología , ARN Viral , Virus de Nápoles de la Fiebre de la Mosca de los Arenales/genética , Virus de Nápoles de la Fiebre de la Mosca de los Arenales/aislamiento & purificación , Turquía/epidemiología , Enfermedades Transmitidas por Vectores/parasitología , Enfermedades Transmitidas por Vectores/transmisión , Enfermedades Transmitidas por Vectores/virología
18.
Viruses ; 12(4)2020 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-32316542

RESUMEN

The genus Orthobunyavirus (family Peribunyaviridae, order Bunyavirales) comprises over 170 named mosquito- and midge-borne viruses, several of which cause severe disease in animals or humans. Their three-segmented genomes enable reassortment with related viruses, which may result in novel viruses with altered host or tissue tropism and virulence. One such reassortant, Schmallenberg virus (SBV), emerged in north-western Europe in 2011. Shuni virus (SHUV) is an orthobunyavirus related to SBV that is associated with neurological disease in horses in southern Africa and recently caused an outbreak manifesting with neurological disease and birth defects among ruminants in Israel. The zoonotic potential of SHUV was recently underscored by its association with neurological disease in humans. We here report a reverse genetics system for SHUV and provide first evidence that the non-structural (NSs) protein of SHUV functions as an antagonist of host innate immune responses. We furthermore report the rescue of a reassortant containing the L and S segments of SBV and the M segment of SHUV. This novel reverse genetics system can now be used to study SHUV virulence and tropism, and to elucidate the molecular mechanisms that drive reassortment events.


Asunto(s)
Infecciones por Bunyaviridae/epidemiología , Infecciones por Bunyaviridae/virología , Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Transmisibles Emergentes/virología , Orthobunyavirus/genética , Genética Inversa , Zoonosis Virales/epidemiología , Zoonosis Virales/virología , Animales , Infecciones por Bunyaviridae/transmisión , Enfermedades Transmisibles Emergentes/transmisión , Genoma Viral , Secuenciación de Nucleótidos de Alto Rendimiento , Ratones , Sistemas de Lectura Abierta , Orthobunyavirus/clasificación , Filogenia , ARN Viral , Ratas , Reino Unido/epidemiología , Zoonosis Virales/transmisión
19.
Am J Trop Med Hyg ; 103(1): 183-189, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32314686

RESUMEN

In 2018, a large outbreak of Rift Valley fever (RVF)-like illness in cattle in Rwanda and surrounding countries was reported. From this outbreak, sera samples from 157 cows and 28 goats suspected to be cases of RVF were tested to confirm or determine the etiology of the disease. Specifically, the hypothesis that orthobunyaviruses-Bunyamwera virus (BUNV), Batai virus (BATV), and Ngari virus (NRIV)-were co-circulating and contributed to RVF-like disease was tested. Using reverse transcriptase-polymerase chain reaction (RT-PCR), RVFV RNA was detected in approximately 30% of acutely ill animals, but in all cases of hemorrhagic disease. Seven cows with experienced abortion had positive amplification and visualization by gel electrophoresis of all three segments of either BUNV or BATV, and three of these were suggested to be coinfected with BUNV and BATV. On sequencing, five of these seven cows were conclusively positive for BUNV. However, in several other animals, sequencing was successful for some but not all segments of targeted viruses BUNV and BATV. In addition, there was evidence of RVFV-orthobunyavirus coinfection, through RT-PCR/gel electrophoresis and subsequent Sanger sequencing. In no cases were we able to definitely identify the specific coinfecting viral species. This is the first time evidence for orthobunyavirus circulation has been molecularly confirmed in Rwanda. Furthermore, RT-PCR results suggest that BUNV and BATV may coinfect cattle and that RVFV-infected animals may be coinfected with other orthobunyaviruses. Finally, we confirm that BUNV and, perhaps, other orthobunyaviruses were co-circulating with RVFV and contributed to the burden of disease attributed to RVFV in Rwanda.


Asunto(s)
Virus Bunyamwera/genética , Infecciones por Bunyaviridae/veterinaria , Enfermedades de los Bovinos/epidemiología , Brotes de Enfermedades , Orthobunyavirus/genética , Fiebre del Valle del Rift/epidemiología , Virus de la Fiebre del Valle del Rift/genética , Animales , Virus Bunyamwera/clasificación , Virus Bunyamwera/aislamiento & purificación , Infecciones por Bunyaviridae/epidemiología , Infecciones por Bunyaviridae/transmisión , Infecciones por Bunyaviridae/virología , Bovinos , Enfermedades de los Bovinos/transmisión , Enfermedades de los Bovinos/virología , Coinfección , Femenino , Cabras/virología , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Epidemiología Molecular , Orthobunyavirus/clasificación , Orthobunyavirus/aislamiento & purificación , ARN Viral/genética , Fiebre del Valle del Rift/transmisión , Fiebre del Valle del Rift/virología , Virus de la Fiebre del Valle del Rift/clasificación , Virus de la Fiebre del Valle del Rift/aislamiento & purificación , Rwanda/epidemiología
20.
Parasit Vectors ; 13(1): 188, 2020 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-32276649

RESUMEN

BACKGROUND: Vector-borne diseases are a major public health concern and cause significant morbidity and mortality. Zika virus (ZIKV) is the etiologic agent of a massive outbreak in the Americas that originated in Brazil in 2015 and shows a strong association with congenital ZIKV syndrome in newborns. Cache Valley virus (CVV) is a bunyavirus that causes mild to severe illness in humans and ruminants. In this study, we investigated the vector competence of Virginia mosquitoes for ZIKV and CVV to explore their abilities to contribute to potential outbreaks. METHODS: To determine vector competence, mosquitoes were fed a blood meal comprised of defibrinated sheep blood and virus. The presence of midgut or salivary gland barriers to ZIKV infection were determined by intrathoracic inoculation vs oral infection. After 14-days post-exposure, individual mosquitoes were separated into bodies, legs and wings, and saliva expectorant. Virus presence was detected by plaque assay to determine midgut infection, dissemination, and transmission rates. RESULTS: Transmission rates for Ae. albopictus orally infected (24%) and intrathoracically inoculated (63%) with ZIKV was similar to Ae. aegypti (48% and 71%, respectively). Transmission rates of ZIKV in Ae. japonicus were low, and showed evidence of a midgut infection barrier demonstrated by low midgut infection and dissemination rates from oral infection (3%), but increased transmission rates after intrathoracic inoculation (19%). Aedes triseriatus was unable to transmit ZIKV following oral infection or intrathoracic inoculation. CVV transmission was dose-dependent where mosquitoes fed high titer (ht) virus blood meals developed higher rates of midgut infection, dissemination, and transmission compared to low titer (lt) virus blood meals. CVV was detected in the saliva of Ae. albopictus (ht: 68%, lt: 24%), Ae. triseriatus (ht: 52%, lt: 7%), Ae. japonicus (ht: 22%, lt: 0%) and Ae. aegypti (ht: 10%; lt: 7%). Culex pipiens and Cx. restuans were not competent for ZIKV or CVV. CONCLUSIONS: This laboratory transmission study provided further understanding of potential ZIKV and CVV transmission cycles with Aedes mosquitoes from Virginia. The ability for these mosquitoes to transmit ZIKV and CVV make them a public health concern and suggest targeted control programs by mosquito and vector abatement districts.


Asunto(s)
Virus Bunyamwera/aislamiento & purificación , Mosquitos Vectores/virología , Virus Zika/aislamiento & purificación , Aedes/virología , Animales , Bioensayo , Sangre/virología , Infecciones por Bunyaviridae/transmisión , Culex/virología , Vectores de Enfermedades , Humanos , Intestinos/virología , Saliva/virología , Estados Unidos , Carga Viral , Virginia , Infección por el Virus Zika/transmisión
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