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1.
Viruses ; 14(12)2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-36560697

RESUMO

In Yangquan County, the sandfly-transmitted virus (Wuxiang virus) was first isolated from sandflies in 2018. However, relationships between the abundance and seasonal fluctuations of local sandflies and sandfly-transmitted viruses are unknown. Herein, we report that sandfly specimens were collected in three villages in Yangquan County, from June to August, 2019. A total of 8363 sandflies were collected (June, 7927; July, 428; August, 8). Eighteen virus strains (June, 18; July, 0; August, 0) were isolated in pools of Phlebotomus chinensis. The genome sequence of the newly isolated virus strain was highly similar to that of the Wuxiang virus (WUXV), isolated from sandflies in Yangquan County in 2018. Our results suggested that the sandfly-transmitted viruses, and the local sandfly population, are stable in Yangquan County, and that June is the peak period for the virus carried by sandflies in this area.


Assuntos
Febre por Flebótomos , Phlebotomus , Phlebovirus , Psychodidae , Animais , Phlebovirus/genética , China
2.
Viruses ; 14(8)2022 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-36016390

RESUMO

According to ICTV, there are currently 66 known phlebovirus species. More than 40 of these viruses were isolated or detected in phlebotomine sandflies and some of them are known pathogens. In Portugal, information about sandfly-borne phleboviruses is scarce and scattered sandfly-borne diseases are neglected and often not considered in differential diagnoses. The main objective of this work was to gather the existing information and to raise awareness about the circulating phleboviruses in this country. To date, Massilia and Alcube phleboviruses have been isolated from sandflies in southern Portugal. Human infections with Toscana and Sicilian phleboviruses have been reported, as well as seroprevalence in cats and dogs. More studies are needed in order to understand if the viruses isolated during the entomological surveys have an impact on human health and to fully understand the real importance of the already recognized pathogens in our country.


Assuntos
Febre por Flebótomos , Phlebovirus , Psychodidae , Animais , Gatos , Cães , Humanos , Febre por Flebótomos/diagnóstico , Febre por Flebótomos/epidemiologia , Portugal/epidemiologia , Estudos Soroepidemiológicos
3.
Front Immunol ; 13: 865797, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35720342

RESUMO

Sandfly fever viruses are emerging Phleboviruses typically causing mild febrile illness. Some strains, however, can cause severe and occasionally fatal neuro-invasive disease. Like most viruses, Phleboviruses have devised various strategies to inhibit the type I interferon (IFN) response to support a productive infection. Still, most of the strategies identified so far focus on inhibiting the sensing arm of the IFN response. In contrast, the effect of sandfly virus infection on signaling from the IFN receptor is less characterized. Therefore, we tested the effect of sandfly fever virus Naples (SFNV) and Sicily (SFSV) infection on IFN signaling. We found that infection with either of these viruses inhibits signaling from the IFN receptor by inhibiting STAT1 phosphorylation and nuclear localization. We show that the viral nonstructural protein NSs mediates these effects, but only NSs from SFNV was found to interact with STAT1 directly. Thus, we tested the upstream IFN signaling components and found that Janus kinase 1 (Jak1) phosphorylation is also impaired by infection. Furthermore, the NSs proteins from both viruses directly interacted with Jak1. Last, we show that IFN inhibition by SFNV and SFSV is most likely downstream of the IFN receptor at the Jak1 level. Overall, our results reveal the multiple strategies used by these related viruses to overcome host defenses.


Assuntos
Interferon Tipo I , Febre por Flebótomos , Phlebovirus , Humanos , Interferon Tipo I/metabolismo , Janus Quinase 1 , Fosforilação , Fator de Transcrição STAT1 , Proteínas não Estruturais Virais/metabolismo
4.
Pediatr Infect Dis J ; 41(7): e299-e300, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35452442

RESUMO

A 3.8-year-old Italian girl presenting with high fever and headache developed a decrease in the state of consciousness, apneas, bradycardia thus requiring intensive care and mechanical ventilation. Sandfly fever due to Cyprus virus, previously not reported in a child, outside an endemic area, must be included in the differential diagnosis of acute encephalopathy with apparently no explanation from the usual laboratory work-up.


Assuntos
Anticorpos Antivirais , Febre por Flebótomos , Criança , Pré-Escolar , Chipre/epidemiologia , Diagnóstico Diferencial , Feminino , Humanos , Itália , Febre por Flebótomos/diagnóstico , Febre por Flebótomos/epidemiologia
5.
Eur J Clin Microbiol Infect Dis ; 41(1): 137-141, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34389911

RESUMO

Toscana virus (TOSV) is emergent in the Mediterranean region and responsible for outbreaks of encephalitis or meningoencephalitis. Sicilian phlebovirus (SFSV) cause epidemics of febrile illness during the summer. The aim of this study was to evaluate the presence of antibodies against TOSV and SFSV in humans in the southwest of Portugal. Neutralizing antibodies to TOSV and SFSV were respectively detected in 5.3% and 4.3% out of 400 human sera tested highlighting the need to increase public health awareness regarding phleboviruses and to include them in the differential diagnosis in patients presenting with fever of short duration and neurological manifestations.


Assuntos
Anticorpos Antivirais/sangue , Febre por Flebótomos/sangue , Febre por Flebótomos/epidemiologia , Febre por Flebótomos/virologia , Phlebovirus/imunologia , Vírus da Febre do Flebótomo Napolitano/imunologia , Adolescente , Adulto , Idoso , Anticorpos Neutralizantes/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Phlebovirus/genética , Portugal/epidemiologia , Vírus da Febre do Flebótomo Napolitano/genética , Estações do Ano , Estudos Soroepidemiológicos , Adulto Jovem
6.
J Gen Virol ; 102(11)2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34726591

RESUMO

Phleboviruses (order Bunyavirales, family Phenuiviridae) are globally emerging arboviruses with a wide spectrum of virulence. Sandfly fever Sicilian virus (SFSV) is one of the most ubiquitous members of the genus Phlebovirus and associated with a self-limited, incapacitating febrile disease in travellers and military troops. The phleboviral NSs protein is an established virulence factor, acting as antagonist of the antiviral interferon (IFN) system. Consistently, we previously reported that SFSV NSs targets the induction of IFN mRNA synthesis by specifically binding to the DNA-binding domain of the IFN transcription factor IRF3. Here, we further characterized the effect of SFSV and its NSs towards IFN induction, and evaluated its potential to affect the downstream IFN-stimulated signalling and the subsequent transactivation of antiviral interferon-stimulated genes (ISGs). We found that SFSV dampened, but did not entirely abolish type I and type III IFN induction. Furthermore, SFSV NSs did not affect IFN signalling, resulting in substantial ISG expression in infected cells. Hence, although SFSV targets IRF3 to reduce IFN induction, it is not capable of entirely disarming the IFN system in the presence of high basal IRF3 and/or IRF7 levels, and we speculate that this significantly contributes to its low level of virulence.


Assuntos
Interferons/imunologia , Febre por Flebótomos/genética , Febre por Flebótomos/virologia , Phlebovirus/imunologia , Interações Hospedeiro-Patógeno , Humanos , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/imunologia , Interferons/genética , Febre por Flebótomos/imunologia , Phlebovirus/genética , Phlebovirus/isolamento & purificação , Phlebovirus/patogenicidade , Regulação para Cima , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/imunologia , Virulência
7.
Viruses ; 13(8)2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34452365

RESUMO

The detection of phleboviruses (family: Phenuiviridae) in human samples is challenged by the overall diversity and genetic complexity of clinically relevant strains, their predominantly nondescript clinical associations, and a related lack of awareness among some clinicians and laboratorians. Here, we seek to inform the detection of human phlebovirus infections by providing a brief introduction to clinically relevant phleboviruses, as well as key targets and approaches for their detection. Given the diversity of pathogens within the genus, this report focuses on diagnostic attributes that are generally shared among these agents and should be used as a complement to, rather than a replacement of, more detailed discussions on the detection of phleboviruses at the individual virus level.


Assuntos
Febre por Flebótomos/diagnóstico , Phlebovirus/genética , Phlebovirus/patogenicidade , Psychodidae/virologia , Animais , Anticorpos Antivirais/sangue , Variação Genética , Humanos , Febre por Flebótomos/imunologia , Febre por Flebótomos/transmissão , Febre por Flebótomos/virologia , Phlebovirus/classificação , Phlebovirus/imunologia , Filogenia , Viremia
8.
Viruses ; 13(8)2021 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-34452524

RESUMO

Sand flies transmit Leishmania infantum, which is responsible for causing leishmaniasis, as well as many phleboviruses, including the human pathogenic Toscana virus. We screened sand flies collected from a single site between 2017 and 2020 for the presence of both phleboviruses and Leishmania. The sand flies were sampled with attractive carbon dioxide traps and CDC light traps between May and October. We collected more than 50,000 sand flies; 2826 were identified at the species level as Phlebotomus perfiliewi (98%) or Phlebotomus perniciosus (2%). A total of 16,789 sand flies were tested in 355 pools, and phleboviruses were found in 61 pools (6 Toscana virus positive pools, 2 Corfou virus positive pools, 42 Fermo virus positive pools, and 7 Ponticelli virus positive pools, and 4 unidentified phlebovirus positive pools). Leishmania was found in 75 pools and both microorganisms were detected in 16 pools. We isolated nine phleboviruses from another 2960 sand flies (five Ponticelli viruses and for Fermo viruses), not tested for Leishmania; the complete genome of a Fermo virus isolate was sequenced. The simultaneous detection in space and time of the Fermo virus and L. infantum is evidence that supports the co-circulation of both microorganisms in the same location and partial overlap of their cycles. A detailed characterization of the epidemiology of these microorganisms will support measures to limit their transmission.


Assuntos
Insetos Vetores/parasitologia , Insetos Vetores/virologia , Leishmania infantum/isolamento & purificação , Phlebotomus/parasitologia , Phlebotomus/virologia , Phlebovirus/isolamento & purificação , Animais , Humanos , Insetos Vetores/classificação , Insetos Vetores/genética , Itália/epidemiologia , Leishmania infantum/genética , Leishmania infantum/fisiologia , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/parasitologia , Leishmaniose Visceral/transmissão , Phlebotomus/classificação , Phlebotomus/genética , Febre por Flebótomos/epidemiologia , Febre por Flebótomos/transmissão , Febre por Flebótomos/virologia , Phlebovirus/genética , Phlebovirus/fisiologia , Filogenia
9.
Front Immunol ; 12: 576640, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34025635

RESUMO

Aspergillus-related disease was confirmed to be associated with immune disorders in patients, severe patients with severe fever with thrombocytopenia syndrome (SFTS) infected by novel phlebovirus were confirmed to have severe immune damage including cellular immunosuppression and cytokine storms. Secondary invasive pulmonary aspergillosis (IPA) in severe SFTS patients can increase fatality rate. This study investigated early-warning predictive factors of secondary IPA in severe SFTS patients. Receiver operating characteristic analysis was used to assess the value of immune parameters to predict IPA in SFTS patients. The cut-off values of CD4+ and CD8+ T-cell counts to predict IPA were 68 and 111 cells/mm3, with sensitivities of 82.6% and 72%, and specificities of 56.7% and 83.3%, respectively. Cut-off values of IL-6, TNF-α, IL-8, and IL-10 to predict IPA incidence in critically ill SFTS patients were 99 pg/mL, 63 pg/mL, 120 pg/mL, and 111 pg/mL, with sensitivities of 90.0%, 86.7%, 83.3% and 90.0% and specificities of 80.4%, 71.7%, 82.6% and 65.2%, respectively. Lower CD4+ and CD8+ T-cells counts, higher levels of IL-6, TNF-α, IL-8 and IL-10, higher incidence of pancreatic and renal damage, early antibacterial therapy of carbapenems, and intensive care unit admission were risk factors of IPA in SFTS patients. Multivariate logistic regression analysis indicated counts of CD4+ T-cells <68 cells/mm3 combined with CD8+ T-cells <111 cells/mm3 (odds ratio [OR] 0.218, 95% confidence interval [CI] 0.059-0.803, p=0.022), IL-6 >99 pg/ml combined with IL-10 >111 pg/ml (OR 17.614, 95% CI 2.319-133.769, p=0.006), and brain natriuretic peptide level >500 pg/ml (OR 13.681, 95% CI 1.994-93.871, p=0.008) were independent risk factors for IPA in SFTS patients. The mortality in the IPA group was significantly higher than in the non-IPA group (p=0.001). Early antifungal treatment of IPA patients was significantly associated with improved survival (log-rank, p=0.022). Early diagnosis of IPA and antifungal treatment can improve the prognosis of SFTS patients. Besides, we speculate SFTS may be as a host factor for IPA.


Assuntos
Aspergilose Pulmonar Invasiva/imunologia , Febre por Flebótomos/imunologia , Phlebovirus/imunologia , Febre Grave com Síndrome de Trombocitopenia/imunologia , Idoso , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Diagnóstico Precoce , Feminino , Humanos , Aspergilose Pulmonar Invasiva/diagnóstico , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Febre por Flebótomos/diagnóstico , Febre por Flebótomos/virologia , Phlebovirus/fisiologia , Prognóstico , Curva ROC , Fatores de Risco , Febre Grave com Síndrome de Trombocitopenia/diagnóstico , Febre Grave com Síndrome de Trombocitopenia/virologia , Índice de Gravidade de Doença , Análise de Sobrevida
10.
Viruses ; 13(5)2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33925561

RESUMO

We report the isolation of a newly recognized phlebovirus, Hedi virus (HEDV), from Phlebotomus chinensis sandflies collected in Shanxi Province, China. The virus' RNA is comprised of three segments. The greatest amino acid sequence similarity of the three gene segments between this virus and previously recognized phleboviruses is 40.85-63.52%, and the RNA-dependent RNA polymerase (RdRp) amino acid sequence has the greatest similarity (63.52%) to the Rift Valley fever virus (RVFV) ZH-548 strain. Phylogenetic analysis of the amino acid sequence of the virus RdRp indicated that HEDV is close to RVFV and distinct from other phleboviruses, forming its own evolutionary branch. We conclude that it is necessary to increase the monitoring of phleboviruses carried by sandflies in China.


Assuntos
Phlebovirus/classificação , Phlebovirus/genética , Psychodidae/virologia , Animais , China , Genoma Viral , Genômica/métodos , Febre por Flebótomos/transmissão , Febre por Flebótomos/virologia , Phlebovirus/isolamento & purificação , Phlebovirus/ultraestrutura , Filogenia , RNA Viral/química , RNA Viral/genética , Replicação Viral , Sequenciamento Completo do Genoma
11.
Viruses ; 13(2)2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33573092

RESUMO

Phleboviruses transmitted by phlebotomine sandflies are endemic in the Mediterranean basin. Toscana phlebovirus (TOSV), Sicilian phlebovirus (SFSV), and Naples phlebovirus (SFNV) are responsible of summer fever, with well-known pathogenic potential for humans ranging from asymptomatic to mild fever, in addition to neuro-invasive infections during summer. Although TOSV, in particular, is a significant and well-known human pathogen, SFVs remain neglected, with many gaps in the relevant knowledge. Sero-epidemiological studies and case reports recently showed a geographical wider distribution than previously considered, although the real incidence of phleboviruses infections in the Mediterranean area is still unknown. Here we retrospectively evaluated the circulation of phleboviruses during summer seasons between 2007 and 2019 in 649 patients showing neurological symptoms using both molecular and serological approaches. We found that 42/649 (6.5%) subjects experienced phlebovirus infection and only 10/42 cases were detected by molecular assays, whereas the other 32/42 were identified using serological approaches, including neutralization assays. During the 2013 summer, an outbreak in the Lombardy region is described because the prevalence of phlebovirus infection reached 37.2% (19/51 subjects). Interestingly, only 5/19 (26.5%) reported traveling in endemic areas. Of note, no cross-neutralization was observed between different strains tested, showing the possibility to be reinfected by newly discovered phlebovirus strains. In conclusion, phlebovirus infections are still inadequately considered by physicians and are generally underestimated. However, based on our results, sandfly fever viruses should be routinely included in diagnostic panels during summer period, including in Northern Italy.


Assuntos
Febre por Flebótomos/diagnóstico , Febre por Flebótomos/epidemiologia , Phlebovirus/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Anticorpos Neutralizantes/sangue , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Febre por Flebótomos/virologia , Phlebovirus/classificação , Phlebovirus/genética , Phlebovirus/imunologia , RNA Viral/genética , Estudos Retrospectivos , Estações do Ano , Adulto Jovem
12.
Viruses ; 13(1)2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33440618

RESUMO

Toscana phlebovirus (TOSV) and Sicilian phlebovirus (SFSV) are endemic in the Mediterranean area where they are transmitted to humans by infected sandflies. Vertebrates of several species have been postulated to act as reservoirs of these viruses, but convincing evidence is still awaited. Among them, bats have been suggested, however documented evidence is lacking. Here we tested a total of 329 bats belonging to eight species collected from twelve localities in southern Spain for the presence of neutralizing antibodies specific to TOSV and SFSV. Positive sera were detected in Schreiber's long-fingered bat (Miniopterus schreibersii), mouse-eared Myotis (Myotis myotis), European free-tailed bat (Tadarida teniotis), and common serotine (Eptesicus serotinus) with the latter showing the highest prevalence rates for SFSV (22.6%) and TOSV (10%). There was no difference between females and males. Results suggest that bats are not likely to play a major role in the natural cycle of these two sandfly-borne phleboviruses. However, large breeding colonies of bats can be used as sentinels for surveillance of the presence of such viruses in a given locality. In addition, capture-recapture studies should be initiated in order to understand better the dynamics of TOSV and SFSV in bat populations.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Quirópteros/imunologia , Quirópteros/virologia , Testes de Neutralização , Febre por Flebótomos/epidemiologia , Febre por Flebótomos/transmissão , Vírus da Febre do Flebótomo Napolitano/imunologia , Animais , Geografia , Testes de Neutralização/métodos , Febre por Flebótomos/imunologia , Vírus da Febre do Flebótomo Napolitano/isolamento & purificação , Estudos Soroepidemiológicos , Espanha/epidemiologia
13.
Arch Virol ; 166(3): 915-919, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33475831

RESUMO

Tick-borne pathogens are an emerging public health threat worldwide. However, information on tick-borne viruses is scanty in sub-Saharan Africa. Here, by RT-PCR, 363 ticks (Amblyomma, Hyalomma and Rhipicephalus) in the Namwala and Livingstone districts of Zambia were screened for tick-borne phleboviruses (TBPVs). TBPVs (L gene) were detected in 19 (5.2%) Rhipicephalus ticks in Namwala. All the detected TBPVs were Shibuyunji viruses. Phylogenetically, they were closely related to American dog tick phlebovirus. This study highlights the possible role of Rhipicephalus ticks as the main host of Shibuyunji virus and suggests that these viruses may be present outside the area where they were initially discovered.


Assuntos
Amblyomma/virologia , Febre por Flebótomos/epidemiologia , Phlebovirus/isolamento & purificação , Rhipicephalus/virologia , Doenças Transmitidas por Carrapatos/epidemiologia , Animais , Variação Genética/genética , Febre por Flebótomos/transmissão , Febre por Flebótomos/virologia , Phlebovirus/genética , Filogenia , Prevalência , Análise de Sequência de DNA , Doenças Transmitidas por Carrapatos/virologia , Zâmbia/epidemiologia
14.
Ann Ig ; 32(6): 674-681, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33175077

RESUMO

BACKGROUND: Toscana virus (TOSV) is an arbovirus transmitted to humans by Phlebotomus spp sandflies. It causes aseptic meningitis and meningoencephalitis with marked seasonality. Here we describe the clinical, microbiological and epidemiological features of two clusters of cases occurred in Tuscany in 2018. METHODS: A confirmed case was defined as the detection of anti-TOSV IgM and IgG in serum sample, in presence of typical clinical manifestations. We consulted hospital records of hospitalized patients to collect clinical information and obtained epidemiological information from the local health authority investigation report. We telephonically interviewed patients using a standard questionnaire for a 6 months follow-up. RESULTS: A total of 12 cases of TOSV meningo-encephalitis with onset between 4th of July and 12th of September accessed health care services in the province of Livorno. Eight cases were males with median age 41,5 and four were not resident in the area. Serological investigations confirmed a recent TOSV infection. Eight cases reported visiting Elba Island and four had a possible occupational-related exposure. CONCLUSIONS: This surge of infection emphasizes the need of information campaigns coupled with adequate surveillance and control interventions against TOSV that, among other arboviruses, is a growing issue of concern in Italy.


Assuntos
Meningoencefalite/epidemiologia , Febre por Flebótomos/epidemiologia , Vírus da Febre do Flebótomo Napolitano , Adulto , Anticorpos Antivirais/sangue , Doenças Transmissíveis Emergentes/epidemiologia , Surtos de Doenças , Feminino , Seguimentos , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Entrevistas como Assunto , Itália/epidemiologia , Masculino , Ilhas do Mediterrâneo/epidemiologia , Meningite Asséptica/diagnóstico , Meningite Asséptica/epidemiologia , Meningoencefalite/diagnóstico , Pessoa de Meia-Idade , Doenças Profissionais/epidemiologia , Febre por Flebótomos/diagnóstico , Vírus da Febre do Flebótomo Napolitano/imunologia , Estações do Ano , Inquéritos e Questionários , Turismo , Doença Relacionada a Viagens , Adulto Jovem
15.
mSphere ; 5(5)2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32878929

RESUMO

Sandfly-transmitted phleboviruses (family Phenuiviridae, order Bunyavirales) are associated with febrile illness and infections of the nervous system in humans. These viruses are almost exclusively found in tropical areas of the New World and restricted to semiarid and temperate zones in the Old World. Here, we discovered seven strains of four previously unknown phleboviruses, named Bogoria virus (BOGV), Embossos virus (EMRV), Kiborgoch virus (KBGV), and Perkerra virus (PERV), as well as the recently discovered Ntepes virus, in sandflies collected in the Kenyan Rift Valley. The genomes have a tripartite organization with conserved termini typical of phleboviruses. LOBV, PERV, and EMBV showed low similarity to known phleboviruses, with less than 55% pairwise amino acid identities in the RNA-directed RNA polymerase (RdRp) proteins, and defined a highly diversified monophyletic clade in sister relationship to the sandfly fever Sicilian serocomplex. All three viruses failed to react with sandfly fever Sicilian virus antisera in recombinant immunofluorescence assays (rIFA), suggesting that the viruses belong to a yet-unknown serogroup. In contrast, KBGV was closely related to Toscana virus (84% identity of RdRp proteins) and shared a most recent common ancestor with the clade comprising sandfly fever Naples and Toscana viruses. KBGV reacted with sandfly fever Naples and Toscana virus antisera in rIFA. The genetic diversity of the detected viruses and their phylogenetic positions implies that the Old World sandfly-borne phleboviruses originated from sub-Saharan Africa. Importantly, our findings suggest that diseases associated with sandfly-borne phlebovirus infections may also affect the Kenyan population.IMPORTANCE Studies on the genetic diversity of arthropod-borne viruses circulating in rural regions can provide critical early indications on new emerging viruses essential for global epidemic preparedness. In this study, we describe the discovery of four phleboviruses in sandflies from the Kenyan Rift Valley. The novel viruses are related to the two medically important serocomplexes, sandfly fever Naples and sandfly fever Sicilian, that are associated with febrile illness and neuroinvasive infections and which were previously not known to occur in sub-Saharan Africa. Knowledge on the occurrence of sandfly-borne phleboviruses in Kenya and elsewhere in Africa can help to decipher their contributions in the etiologies of fevers of unknown origin in patients. Our findings on five genetically diverse phleboviruses detected in Kenya suggest that the common ancestor of Old World phleboviruses existed in sub-Saharan Africa, a hot spot for emerging arboviruses.


Assuntos
Evolução Molecular , Variação Genética , Febre por Flebótomos/virologia , Phlebovirus/classificação , Phlebovirus/genética , Animais , Humanos , Quênia , Filogenia , Psychodidae/virologia , Vírus da Febre do Flebótomo Napolitano/genética , Proteínas Virais/genética
16.
Infect Genet Evol ; 85: 104524, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32891876

RESUMO

Phlebovirus is an abundant and rather heterogeneous genus within the Phenuiviridae family (order Bunyavirales). The genus Phlebovirus is divided into two antigenic complexes, which also correspond to the main vector: sandflies/mosquitoes and ticks. Previously, only sandfly/mosquito-borne phleboviruses were associated with human disease, such as Rift Valley fever virus, Toscana virus, Sicilian and Naples Sandfly fever viruses and others. Until recently, tick-borne phleboviruses were not considered as human pathogens. After the discovery of severe fever with thrombocytopenia syndrome, interest to tick-borne phleboviruses has increased dramatically. In the last decade, many novel phleboviruses have been reported in different regions. Despite this, the diversity, ecology and pathogenicity of these viruses still remain obscure. The aim of this work was to study the diversity of phleboviruses in ticks collected in several regions of Russia. We used pan-phlebovirus RT-PCR assays based on multiple degenerate primers targeting the polymerase gene fragment. Arthropod specimens were collected from 2005 to 2018. A total of 5901 Ixodidae ticks combined into 1116 pools were screened. A total of 160 specific amplicons were produced. In three cases RT-PCR assays amplified two distinct viruses from same tick pools. Direct sequencing of amplicons and subsequent phylogenetic analysis revealed twelve representatives of divergent phlebovirus groups. Based on the distribution of pairwise nucleotide sequence identity values, a cut-off (88%) was suggested to distinguish tick-borne phleboviruses. According to this provisional criterion, two viruses found here could be termed novel, while ten viruses have been described in previous studies. Detected phleboviruses demonstrated almost perfect specificity to a tick species or, at least, a genus. The same pattern was observed for tick-borne phleboviruses found in different studies around the world. Viruses that grouped together on a phylogenetic tree and differed less than this sequence identity threshold suggested above were hosted by ticks from the same genus.


Assuntos
Febre por Flebótomos/genética , Phlebovirus/classificação , Phlebovirus/genética , Filogenia , Especificidade da Espécie , Doenças Transmitidas por Carrapatos/genética , Carrapatos/virologia , Animais , Variação Genética , Genótipo , Febre por Flebótomos/epidemiologia , Federação Russa , Análise de Sequência , Doenças Transmitidas por Carrapatos/epidemiologia
17.
BMC Infect Dis ; 20(1): 595, 2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32787952

RESUMO

BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS) is a severe systemic virus infectious disease usually having multi-organ dysfunction which resembles sepsis. METHODS: Data of 321 patients with laboratory-confirmed SFTS from May 2013 to July 2017 were retrospectively analyzed. Demographic and clinical characteristics, calculated quick sequential organ failure assessment (qSOFA) score and systemic inflammatory response syndrome (SIRS) criteria for survivors and nonsurvivors were compared. Independent risk factors associated with in-hospital mortality were obtained using multivariable logistic regression analysis. Risk score models containing different risk factors for mortality in stratified patients were established whose predictive values were evaluated using the area under ROC curve (AUC). RESULTS: Of 321 patients, 87 died (27.1%). Age (p < 0.001) and percentage numbers of patients with qSOFA≥2 and SIRS≥2 (p < 0.0001) were profoundly greater in nonsurvivors than in survivors. Age, qSOFA score, SIRS score and aspartate aminotransferase (AST) were independent risk factors for mortality for all patients. qSOFA score was the only common risk factor in all patients, those age ≥ 60 years and those enrolled in the intensive care unit (ICU). A risk score model containing all these risk factors (Model1) has high predictive value for in-hospital mortality in these three groups with AUCs (95% CI): 0.919 (0.883-0.946), 0.929 (0.862-0.944) and 0.815 (0.710-0.894), respectively. A model only including age and qSOFA also has high predictive value for mortality in these groups with AUCs (95% CI): 0.872 (0.830-0.906), 0.885(0.801-0.900) and 0.865 (0.767-0.932), respectively. CONCLUSIONS: Risk models containing qSOFA have high predictive validity for SFTS mortality.


Assuntos
Escores de Disfunção Orgânica , Febre por Flebótomos/complicações , Febre por Flebótomos/mortalidade , Phlebovirus/genética , Trombocitopenia/complicações , Trombocitopenia/mortalidade , Fatores Etários , Idoso , Área Sob a Curva , Aspartato Aminotransferases/sangue , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Febre por Flebótomos/sangue , Prognóstico , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco , Sepse/mortalidade , Síndrome
18.
BMC Infect Dis ; 20(1): 575, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32758175

RESUMO

BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease with the high case-fatality rate, and lack of vaccines. We aimed to systematically analysed the epidemiological characteristics, clinical signs, routine laboratory diagnosis, risk factors, and outcomes. METHODS: Documents on SFTS were collected by searching the Chinese National Knowledge Infrastructure, Wan Fang Data, PubMed, Embase, and Web of Science databases from 2011 to 2018. Meta-analysis was performed by using Review Manager and Stata software. RESULTS: Twenty-five articles involving 4143 cases were included. Diarrhea (odds ratio (OR) =1.60, 95% confidence interval (CI): 1.06 to 2.42, P = 0.02), and vomiting (OR = 1.56, 95% CI: 1.01 to 2.39, P = 0.04) on admission were associated with the fatal outcomes of SFTS. Compared to patients with mild symptoms, patients with severe symptoms had significantly elevated levels of lactic acid dehydrogenase (standard mean difference (SMD) =1.27, 95% CI: 0.59 to 1.94), alanine aminotransferase (SMD = 0.55, 95% CI: 0.24 to 0.85), aspirate aminotransferase (SMD = 1.01, 95% CI: 0.69 to 1.32), and creatine kinase (SMD = 1.04, 95% CI: 0.74 to 1.33) but had reduced platelet counts (SMD = -0.87, 95% CI: - 1.16 to - 0.58) and albumin levels (SMD = -1.00, 95% CI: - 1.32 to - 0.68). The risk factors for poor prognosis included age (mean difference (MD) =6.88, 95% CI: 5.41 to 8.35) and farming (OR = 2.01, 95% CI: 1.06 to 3.80). For the risk factors of contracting SFTS, the incidence of SFTS related to tick bites was 24% [95% CI: 0.18 to 0.31]. The pooled case-fatality rate of SFTS patients was 18% [95% CI: 0.16 to 0.21]. CONCLUSIONS: China is the country with the highest incidence of SFTS. May to July was the peak of the epidemic, and farmers were a high-risk group. The risk factor for SFTS included age (poor prognosis) and tick bites (contracting SFTS). Patients with severe diarrhea and vomiting symptoms on admission should be noted. Clinicians could use routine laboratory parameters and clinical symptoms as references for clinically suspected cases, classification of SFTS, and timely treatment, especially in basic hospitals.


Assuntos
Doenças Transmissíveis Emergentes/epidemiologia , Epidemias , Febre por Flebótomos/complicações , Febre por Flebótomos/epidemiologia , Phlebovirus/imunologia , Trombocitopenia/complicações , Trombocitopenia/epidemiologia , Idoso , Anticorpos Antivirais/sangue , China/epidemiologia , Doenças Transmissíveis Emergentes/sangue , Doenças Transmissíveis Emergentes/virologia , Fazendeiros , Feminino , Febre/complicações , Humanos , Incidência , Leucopenia/complicações , Masculino , Pessoa de Meia-Idade , Febre por Flebótomos/sangue , Febre por Flebótomos/virologia , Phlebovirus/isolamento & purificação , RNA Viral/sangue , Fatores de Risco , Síndrome , Trombocitopenia/virologia
19.
Arch Virol ; 165(11): 2599-2603, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32699980

RESUMO

Severe fever with thrombocytopenia syndrome (SFTS) is caused by SFTS virus (SFTSV). Although SFTS originated in China, it is an emerging infectious disease with prevalence confirmed in Japan, Korea, and Vietnam. The full-length genomes of 51 Korean SFTSV isolates from 2013 to 2016 were sequenced, and the sequences were deposited into a public database (GenBank) and analyzed to elucidate the phylogeny and evolution of the virus. Although most of the Korean SFTSV isolates were closely related to previously reported Japanese isolates, some were closely related to previously reported Chinese isolates. We identified one Korean strain that appears to have resulted from multiple inter-lineage reassortments. Several nucleotide and amino acid variations specific to the Korean isolates were identified. Future studies should focus on how these variations affect virus pathogenicity and evolution.


Assuntos
Infecções por Bunyaviridae/virologia , Febre por Flebótomos/virologia , Phlebovirus/genética , Sequência de Bases , China , Evolução Molecular , Variação Genética , Genótipo , Humanos , Japão , Phlebovirus/classificação , Phlebovirus/isolamento & purificação , Filogenia , República da Coreia , Análise de Sequência de DNA , Trombocitopenia/virologia
20.
Emerg Infect Dis ; 26(7): 1612-1614, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32568054

RESUMO

We report on a 70-year-old man with fever, leukopenia, thrombocytopenia, vomiting, malaise, dyspnea, and consciousness disturbance who was infected with severe fever with thrombocytopenia syndrome virus in northern Taiwan, 2019. This autochthonous case was confirmed by reverse transcription PCR, virus isolation, and genomic sequencing.


Assuntos
Infecções por Bunyaviridae , Leucopenia , Febre por Flebótomos , Phlebovirus , Febre Grave com Síndrome de Trombocitopenia , Idoso , Infecções por Bunyaviridae/diagnóstico , Humanos , Masculino , Phlebovirus/genética , Taiwan
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