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1.
Artigo em Inglês | MEDLINE | ID: mdl-38651618

RESUMO

Background: Hepatitis E virus (HEV) is transmitted by the fecal route, usually through contaminated water in humans and/or infected animals, especially pigs. The objective of this study was to evaluate the level of anti-HEV antibodies in a panel of pig sera and to identify HEV in pig feces in farms. Methodology: The presence of HEV antibodies was tested by an in-house ELISA and a commercial ELISA IDvet. HEV genome was assessed by nested RT-PCR, and then, genotype was identified by sequencing (MinION Nanopore technology). Results: In 2017-2019, the 43% seroprevalence found in Forest Guinea was significantly higher than the 7% found in the Lower region (p < 0.01). Presence of HEV genotype 3c was demonstrated during a secondary study in the Lower region (Conakry) in 2022. Conclusion: The presence of HEV-3c in pigs calls for an evaluation of seroprevalence in human populations and for a HEV genotype human circulation check. Contribution Heading: This study is the first report, to our knowledge, of seroprevalence and characterization of HEV infection in pigs in Guinea.

2.
Viruses ; 16(4)2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38675900

RESUMO

Hepatitis E virus (HEV) is the main cause of acute hepatitis in humans worldwide and is responsible for a large number of outbreaks especially in Africa. Human infections are mainly caused by genotypes 1 and 2 of the genus Paslahepevirus, which are exclusively associated with humans. In contrast, viruses of genotypes 3 and 4 are zoonotic and have their main reservoir in domestic and wild pigs, from which they can be transmitted to humans primarily through the consumption of meat products. Both genotypes 3 and 4 are widespread in Europe, Asia, and North America and lead to sporadic cases of hepatitis E. However, there is little information available on the prevalence of these genotypes and possible transmission routes from animal reservoirs to humans in African countries. We therefore analysed 1086 pig sera collected in 2016/2017 in four districts in Sierra Leone for antibodies against HEV using a newly designed in-house ELISA. In addition, the samples were also analysed for HEV RNA by quantitative real-time RT-PCR. The overall seroprevalence in Sierra Leone was low with only 44 positive sera and a prevalence of 4.0%. Two serum pools were RT-PCR-positive and recovered partial sequences clustered into the genotype 3 (HEV-3) of the order Paslahepevirus, species Paslahepevirus balayani. The results are the first evidence of HEV-3 infection in pigs from Sierra Leone and demonstrate a low circulation of the virus in these animals to date. Further studies should include an examination of humans, especially those with close contact with pigs and porcine products, as well as environmental sampling to evaluate public health effects within the framework of a One Health approach.


Assuntos
Genótipo , Vírus da Hepatite E , Hepatite E , Filogenia , Doenças dos Suínos , Animais , Hepatite E/epidemiologia , Hepatite E/veterinária , Hepatite E/virologia , Vírus da Hepatite E/genética , Vírus da Hepatite E/classificação , Vírus da Hepatite E/isolamento & purificação , Vírus da Hepatite E/imunologia , Estudos Soroepidemiológicos , Suínos , Doenças dos Suínos/virologia , Doenças dos Suínos/epidemiologia , Serra Leoa/epidemiologia , Anticorpos Anti-Hepatite/sangue , RNA Viral/genética , Sus scrofa/virologia , Humanos
3.
Virulence ; 15(1): 2329447, 2024 12.
Artigo em Inglês | MEDLINE | ID: mdl-38548679

RESUMO

MicroRNAs (miRNAs) are small non-coding RNAs that regulate the post-transcriptional expression of target genes. Virus-encoded miRNAs play an important role in the replication of viruses, modulate gene expression in both the virus and host, and affect their persistence and immune evasion in hosts. This renders viral miRNAs as potential targets for therapeutic applications, especially against pathogenic viruses that infect humans and animals. Rift Valley fever virus (RVFV) is a mosquito-borne zoonotic RNA virus that causes severe disease in both humans and livestock. High mortality among newborn lambs and abortion storms are key characteristics of an RVF outbreak. To date, limited information is available on RVFV-derived miRNAs. In this study, computational methods were used to analyse the RVFV genome for putative pre-miRNA genes, which were then analysed for the presence of mature miRNAs. We detected 19 RVFV-encoded miRNAs and identified their potential mRNAs targets in sheep (Ovis aries), the most susceptible host. The identification of significantly enriched O. aries genes in association with RVFV miRNAs will help elucidate the molecular mechanisms underlying RVFV pathogenesis and potentially uncover novel drug targets for RVFV.


Assuntos
Culicidae , MicroRNAs , Febre do Vale de Rift , Vírus da Febre do Vale do Rift , Humanos , Gravidez , Feminino , Animais , Ovinos/genética , Vírus da Febre do Vale do Rift/genética , Febre do Vale de Rift/genética , Febre do Vale de Rift/epidemiologia , Culicidae/genética , Surtos de Doenças , MicroRNAs/genética
4.
J Med Chem ; 67(1): 289-321, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38127656

RESUMO

The synthesis of a library of halogenated rocaglate derivatives belonging to the flavagline class of natural products, of which silvestrol is the most prominent example, is reported. Their antiviral activity and cytotoxicity profile against a wide range of pathogenic viruses, including hepatitis E, Chikungunya, Rift Valley Fever virus and SARS-CoV-2, were determined. The incorporation of halogen substituents at positions 4', 6 and 8 was shown to have a significant effect on the antiviral activity of rocaglates, some of which even showed enhanced activity compared to CR-31-B and silvestrol.


Assuntos
Febre de Chikungunya , Vírus da Hepatite E , Vírus , Animais , Antivirais/farmacologia
5.
J Clin Microbiol ; 61(11): e0037323, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37823649

RESUMO

The consumption of raw or undercooked meat products poses a serious risk for human hepatitis E virus (HEV) infections. In many high-income countries, domestic pigs and wild boars represent the main animal reservoirs for HEV and are usually identified by reverse transcription-PCR and antibody enzyme-linked immunosorbent assay (ELISA). In order to characterize the humoral immune response in more detail, a cell culture-based serum neutralization assay using a culture-adapted HEV strain was established here. Measurement of neutralizing antibodies was only possible after removing the viral quasi-envelope by detergent treatment. Serum samples of 343 wild boars from Northern Germany were first analyzed for anti-HEV IgG using an in-house ELISA, resulting in 19% positive samples. Subsequently, a subset of 41 representative samples was tested with the neutralization assay, and the results correlated well with those obtained by ELISA. Not only the human HEV strain 47832c but also two porcine HEV strains were shown to be neutralized by porcine serum antibodies. Neutralizing activity was also found in samples containing both HEV-specific antibodies and HEV RNA. Testing of serum samples derived from two experimentally infected domestic pigs showed a steep increase in neutralizing activity at 24 or 51 days post infection, dependent on the used infectious dose. The developed assay can be useful for characterization of the humoral immune response after HEV infection and for assessing the efficiency of HEV vaccine candidates.


Assuntos
Vírus da Hepatite E , Hepatite E , Doenças dos Suínos , Suínos , Animais , Humanos , Vírus da Hepatite E/genética , Sus scrofa/genética , Anticorpos Anti-Hepatite , Ensaio de Imunoadsorção Enzimática , RNA Viral
6.
Pathogens ; 11(12)2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36558837

RESUMO

On the African continent, a large number of arthropod-borne viruses (arboviruses) with zoonotic potential have been described, and yet little is known of most of these pathogens, including their actual distribution or genetic diversity. In this study, we evaluated as a proof-of-concept the effectiveness of the nonspecific sequencing technique sequence-independent single primer amplification (SISPA) on third-generation sequencing techniques (MinION sequencing, Oxford Nanopore Technologies, Oxford, UK) by comparing the sequencing results from six different samples of arboviruses known to be circulating in Africa (Crimean-Congo hemorrhagic fever virus (CCHFV), Rift Valley fever virus (RVFV), Dugbe virus (DUGV), Nairobi sheep disease virus (NSDV), Middleburg virus (MIDV) and Wesselsbron virus (WSLV)). All sequenced samples were derived either from previous field studies or animal infection trials. Using this approach, we were able to generate complete genomes for all six viruses without the need for virus-specific whole-genome PCRs. Higher Cq values in diagnostic RT-qPCRs and the origin of the samples (from cell culture or animal origin) along with their quality were found to be factors affecting the success of the sequencing run. The results of this study may stimulate the use of metagenomic sequencing approaches, contributing to a better understanding of the genetic diversity of neglected arboviruses.

7.
Viruses ; 14(11)2022 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-36423168

RESUMO

Unlike farm animals, wild animals are not subject to continuous health surveillance. Individual projects designed to screen wildlife populations for specific pathogens are, therefore, also of great importance for human health. In this context, the possible formation of a reservoir for highly pathogenic zoonotic pathogens is a focus of research. Two of these pathogens that have received particular attention during the last years are the novel severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), due to its fast global spread and high impact to the human health, and, since its introduction into Germany, the flavivirus West Nile virus (WNV). Especially in combination with invasive vertebrate species (e.g., raccoons (Procyon lotor) and raccoon dogs (Nyctereutes procyonoides) in Germany), risk analysis must be done to enable health authorities to assess the potential for the establishment of new wild life reservoirs for pathogens. Therefore, samples were collected from raccoons and raccoon dogs and analyzed for the presence of SARS-CoV-2 and WNV infections in these populations. Molecular biological and serological data obtained imply that no SARS-CoV-2 nor WNV reservoir has been established in these two wild life species yet. Future investigations need to keep an eye on these invasive carnivore populations, especially since the close contact of these animals to humans, mainly in urban areas, would make animal-human transmission a challenge for human health.


Assuntos
COVID-19 , Vírus do Nilo Ocidental , Animais , Humanos , Guaxinins , Cães Guaxinins , SARS-CoV-2 , Estudos Transversais , COVID-19/epidemiologia , COVID-19/veterinária , Alemanha/epidemiologia , Animais Selvagens
8.
Viruses ; 14(11)2022 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-36366585

RESUMO

Rift Valley fever phlebovirus (RVFV) causes Rift Valley fever (RVF), an emerging zoonotic disease that causes abortion storms and high mortality rates in young ruminants as well as severe or even lethal complications in a subset of human patients. This study investigates the pathomechanism of intranuclear inclusion body formation in severe RVF in a mouse model. Liver samples from immunocompetent mice infected with virulent RVFV 35/74, and immunodeficient knockout mice that lack interferon type I receptor expression and were infected with attenuated RVFV MP12 were compared to livers from uninfected controls using histopathology and immunohistochemistry for RVFV nucleoprotein, non-structural protein S (NSs) and pro-apoptotic active caspase-3. Histopathology of the livers showed virus-induced, severe hepatic necrosis in both mouse strains. However, immunohistochemistry and immunofluorescence revealed eosinophilic, comma-shaped, intranuclear inclusions and an intranuclear (co-)localization of RVFV NSs and active caspase-3 only in 35/74-infected immunocompetent mice, but not in MP12-infected immunodeficient mice. These results suggest that intranuclear accumulation of RVFV 35/74 NSs is involved in nuclear translocation of active caspase-3, and that nuclear NSs and active caspase-3 are involved in the formation of the light microscopically visible inclusion bodies.


Assuntos
Febre do Vale de Rift , Vírus da Febre do Vale do Rift , Humanos , Animais , Camundongos , Caspase 3 , Proteínas não Estruturais Virais/metabolismo , Ruminantes , Corpos de Inclusão/metabolismo
9.
Transbound Emerg Dis ; 69(6): 3317-3324, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35986711

RESUMO

The hepatitis E virus (HEV) is the main cause of viral acute hepatitis in the world, affecting more than 20 million people annually. During the acute phase of infection, HEV can be detected in various body fluids, which has a significant impact in terms of transmission, diagnosis or extrahepatic manifestations. Several studies have isolated HEV in the genitourinary tract of humans and animals, which could have important clinical and epidemiological implications. So, our main objective was to evaluate the presence of HEV in testis of naturally infected wild boars (Sus scrofa). For it, blood, liver, hepatic lymph node and testicle samples were collected from 191 male wild boars. The presence of HEV was evaluated in serum by PCR, as well as in tissues by PCR and immunohistochemistry. Four animals (2.09%; 95%CI: 0.82-5.26) showed detectable HEV RNA in serum, being confirmed the presence of HEV-3f genotype in three of them by phylogenetic analysis. HEV was also detected in liver and/or hepatic lymph nodes of the four animals by RT-PCR, as well as by immunohistochemistry analysis. Only one of these wild boars also showed detectable viral load in testis, observing HEV-specific labelling in a small number of fibroblasts and some Sertoli cells. Our results confirm the presence of HEV genotype 3 in naturally infected wild boar testis, although no associated tissue damage was evidenced. This study does not allow us to discard semen as a possible source of HEV transmission in suids. Future experimental studies are necessary to evaluate the impact of HEV genotype 3 on fertility and the possibility of transmission through sexual contact in this specie.


Assuntos
Vírus da Hepatite E , Hepatite E , Doenças dos Suínos , Humanos , Animais , Masculino , Suínos , Hepatite E/epidemiologia , Hepatite E/veterinária , Testículo , Filogenia , RNA Viral/genética , Genótipo , Sus scrofa
10.
Pathogens ; 11(7)2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35890018

RESUMO

Hepatitis E is a major cause of acute liver disease in humans worldwide. The infection is caused by hepatitis E virus (HEV) which is transmitted in Europe to humans primarily through zoonotic foodborne transmission from domestic pigs, wild boar, rabbits, and deer. HEV belongs to the family Hepeviridae, and possesses a positive-sense, single stranded RNA genome. This agent usually causes an acute self-limited infection in humans, but in people with low immunity, e.g., immunosuppressive therapy or underlying liver diseases, the infection can evolve to chronicity and is able to induce a variety of extrahepatic manifestations. Pig and wild boar have been identified as the primary animal reservoir in Europe, and consumption of raw and undercooked pork is known to pose a potential risk of foodborne HEV infection. In this study, we analysed pig and wild boar liver, faeces, and muscle samples collected in 2019 in Mecklenburg-Western Pomerania, north-east Germany. A total of 393 animals of both species were investigated using quantitative real-time reverse transcription polymerase chain reaction (RT-qPCR), conventional nested RT-PCR and sequence analysis of amplification products. In 33 animals, HEV RNA was detected in liver and/or faeces. In one individual, viral RNA was detected in muscle tissue. Sequence analysis of a partial open reading frame 1 region demonstrated a broad variety of genotype 3 (HEV-3) subtypes. In conclusion, the study demonstrates a high, but varying prevalence of HEV RNA in swine populations in Mecklenburg-Western Pomerania. The associated risk of foodborne HEV infection needs the establishment of sustainable surveillance and treatment strategies at the interface between humans, animals, and the environment within a One Health framework.

11.
Viruses ; 14(6)2022 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-35746790

RESUMO

West Nile virus (WNV) is an emerging infectious pathogen circulating between mosquitoes and birds but also infecting mammals. WNV has become autochthonous in Germany, causing striking mortality rates in avifauna and occasional diseases in humans and horses. We therefore wanted to assess the possible role of free-ranging poultry in the WNV transmission cycle and infected 15 goslings with WNV lineage 2 (German isolate). The geese were monitored daily and sampled regularly to determine viremia, viral shedding, and antibody development by molecular and serological methods. Geese were euthanized at various time points post-infection (pi). All infected geese developed variable degrees of viremia from day 1 to day 10 (maximum) and actively shed virus from days 2 to 7 post-infection. Depending on the time of death, the WN viral genome was detected in all examined tissue samples in at least one individual by RT-qPCR and viable virus was even re-isolated, except for in the liver. Pathomorphological lesions as well as immunohistochemically detectable viral antigens were found mainly in the brain. Furthermore, all of the geese seroconverted 6 days pi at the latest. In conclusion, geese are presumably not functioning as important amplifying hosts but are suitable sentinel animals for WNV surveillance.


Assuntos
Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Anticorpos Antivirais , Gansos , Cavalos , Mamíferos , Viremia/veterinária , Vírus do Nilo Ocidental/genética
12.
Microorganisms ; 10(4)2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35456857

RESUMO

West Nile virus (WNV) and Usutu virus (USUV) are important flaviviruses circulating in Germany. While USUV was first reported more than 10 years ago, WNV has only reached the country in 2018. Wild birds are important amplifying hosts for both viruses. Therefore, we have been monitoring the bird population in different regions of Germany by a previously established network for many years. This report summarizes the results of molecular and/or serological methods of 2345 blood samples from birds of 22 different orders and over 2900 bird carcasses from 2019 and 2020. USUV RNA circulation was found in different regions of Germany, with emphasis on USUV lineages Europe 3 and Africa 3. Increased evidence of USUV lineage Europe 2 was detected in eastern Germany. WNV RNA was found only in birds from the eastern part of the country. The seroprevalence for USUV was between 3.11% and 7.20% in all three regions investigated, whereas the WNV seroprevalence spanned from 14.77% to 16.15% in eastern Germany, with a noticeable tendency for a westward and southward expansion in both years. Thus, wild bird monitoring for WNV and USUV can serve as an early warning system for a human exposure risk.

13.
PLoS Negl Trop Dis ; 16(4): e0010203, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35427361

RESUMO

In Mauritania, several mosquito-borne viruses have been reported that can cause devastating diseases in animals and humans. However, monitoring data on their occurrence and local distribution are limited. Rift Valley fever virus (RVFV) is an arthropod-borne virus that causes major outbreaks throughout the African continent and the Arabian Peninsula. The first Rift Valley fever (RVF) epidemic in Mauritania occurred in 1987 and since then the country has been affected by recurrent outbreaks of the disease. To gain information on the occurrence of RVFV as well as other mosquito-borne viruses and their vectors in Mauritania, we collected and examined 4,950 mosquitoes, belonging to four genera and 14 species. The mosquitoes were captured during 2018 in the capital Nouakchott and in southern parts of Mauritania. Evidence of RVFV was found in a mosquito pool of female Anopheles pharoensis mosquitoes collected in December on a farm near the Senegal River. At that time, 37.5% of 16 tested Montbéliarde cattle on the farm showed RVFV-specific IgM antibodies. Additionally, we detected IgM antibodies in 10.7% of 28 indigenous cattle that had been sampled on the same farm one month earlier. To obtain information on potential RVFV reservoir hosts, blood meals of captured engorged mosquitoes were analyzed. The mosquitoes mainly fed on humans (urban areas) and cattle (rural areas), but also on small ruminants, donkeys, cats, dogs and straw-colored fruit bats. Results of this study demonstrate the circulation of RVFV in Mauritania and thus the need for further research to investigate the distribution of the virus and its vectors. Furthermore, factors that may contribute to its maintenance should be analyzed more closely. In addition, two mosquito pools containing Aedes aegypti and Culex quinquefasciatus mosquitoes showed evidence of dengue virus (DENV) 2 circulation in the city of Rosso. Further studies are therefore needed to also examine DENV circulation in Mauritania.


Assuntos
Aedes , Vírus da Dengue , Comportamento Alimentar , Flavivirus , Vírus da Febre do Vale do Rift , Animais , Bovinos , Feminino , Flavivirus/isolamento & purificação , Imunoglobulina M , Mauritânia/epidemiologia , Mosquitos Vetores , Vírus da Febre do Vale do Rift/isolamento & purificação
14.
Pathogens ; 11(3)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35335679

RESUMO

Zoonotic hepatitis E virus (HEV) infection is an emerging cause of acute viral hepatitis in developed countries. Known reservoirs of zoonotic genotype 3 (HEV-3) are mainly pigs and wild boar, and to a lesser extent rabbits and deer. Rabbit hepatitis E virus (HEV-3ra) is prevalent in rabbits worldwide and represents a particular risk for zoonotic infection. Current understanding of the molecular mechanisms of HEV pathogenesis is incomplete, particularly due to the limited availability of efficient and reliable cell culture systems. In order to identify genomic regions responsible for HEV propagation in cell culture, we developed a modular chimeric reporter replicon system based on cell culture-adapted (Kernow-C1/p6 and 47832mc) and rabbit-derived HEV strains. Replication in HepG2 cells was monitored on the basis of a Gaussia luciferase reporter gene that was inserted in place of the open reading frame (ORF) 2 of the HEV genome. Luciferase activity of rabbit HEV-derived replicons was significantly lower than that of Kernow-C1/p6 and 47832mc replicons. Serial exchanges of defined ORF1 segments within the Kernow-C1/p6 replicon backbone indicated that HEV replication in HepG2 cells is not determined by a single domain but rather by an interplay of longer segments of the ORF1-derived nonstructural polyprotein. This implies that a specific combination of viral factors is required for efficient HEV propagation in cell culture.

15.
Viruses ; 14(2)2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35215938

RESUMO

Rift Valley fever (RVF) is a zoonotic disease caused by RVF Phlebovirus (RVFV). The RVFV MP-12 vaccine strain is known to exhibit residual virulence in the case of a deficient interferon type 1 response. The hypothesis of this study is that virus replication and severity of lesions induced by the MP-12 strain in immunocompromised mice depend on the specific function of the disturbed pathway. Therefore, 10 strains of mice with deficient innate immunity (B6-IFNARtmAgt, C.129S7(B6)-Ifngtm1Ts/J, B6-TLR3tm1Flv, B6-TLR7tm1Aki, NOD/ShiLtJ), helper T-cell- (CD4tm1Mak), cytotoxic T-cell- (CD8atm1Mak), B-cell- (Igh-Jtm1DhuN?+N2), combined T- and B-cell- (NU/J) and combined T-, B-, natural killer (NK) cell- and macrophage-mediated immunity (NOD.Cg-PrkdcscidIl2rgtm1WjI/SzJ (NSG) mice) were subcutaneously infected with RVFV MP-12. B6-IFNARtmAgt mice were the only strain to develop fatal disease due to RVFV-induced severe hepatocellular necrosis and apoptosis. Notably, no clinical disease and only mild multifocal hepatocellular necrosis and apoptosis were observed in NSG mice, while immunohistochemistry detected the RVFV antigen in the liver and the brain. No or low virus expression and no lesions were observed in the other mouse strains. Conclusively, the interferon type 1 response is essential for early control of RVFV replication and disease, whereas functional NK cells, macrophages and lymphocytes are essential for virus clearance.


Assuntos
Imunidade Adaptativa , Imunidade Inata , Febre do Vale de Rift/imunologia , Vírus da Febre do Vale do Rift/fisiologia , Animais , Apoptose , Feminino , Humanos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/virologia , Fígado/imunologia , Fígado/virologia , Macrófagos/imunologia , Macrófagos/virologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Febre do Vale de Rift/genética , Febre do Vale de Rift/fisiopatologia , Febre do Vale de Rift/virologia , Vírus da Febre do Vale do Rift/genética , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/virologia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/virologia
16.
Transbound Emerg Dis ; 69(2): 776-792, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33655706

RESUMO

The emergence of West Nile virus (WNV) and Usutu virus (USUV) in Europe resulted in significant outbreaks leading to avifauna mortality and human infections. Both viruses have overlapping geographical, host and vector ranges, and are often co-circulating in Europe. In Germany, a nationwide bird surveillance network was established to monitor these zoonotic arthropod-borne viruses in migratory and resident birds. In this framework, co-infections with WNV and USUV were detected in six dead birds collected in 2018 and 2019. Genomic sequencing and phylogenetic analyses classified the detected WNV strains as lineage 2 and the USUV strains as lineages Africa 2 (n = 2), Africa 3 (n = 3) and Europe 2 (n = 1). Preliminary attempts to co-propagate both viruses in vitro failed. However, we successfully cultivated WNV from two animals. Further evidence for WNV-USUV co-infection was obtained by sampling live birds in four zoological gardens with confirmed WNV cases. Three snowy owls had high neutralizing antibody titres against both WNV and USUV, of which two were also positive for USUV-RNA. In conclusion, further reports of co-infections in animals as well as in humans are expected in the future, particularly in areas where both viruses are present in the vector population.


Assuntos
Doenças das Aves , Coinfecção , Infecções por Flavivirus , Flavivirus , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Doenças das Aves/epidemiologia , Aves , Coinfecção/epidemiologia , Coinfecção/veterinária , Flavivirus/genética , Infecções por Flavivirus/veterinária , Alemanha/epidemiologia , Filogenia , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/genética
17.
Transbound Emerg Dis ; 69(4): 2173-2181, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34212525

RESUMO

Livestock industry supports the livelihood of around 1.3 billion people in the world, with swine industry contributing with 30% of total livestock production worldwide. To maintain and guarantee this production, a pivotal point according to the OIE is addressing potential biohazards. To control them, permanent sero-surveillance is crucial to achieve more focused veterinary public health intervention and prevention strategies, to break the chains of transmission, and to enable fast responses against outbreaks. Within this context, multiplex assays are powerful tools with the potential to simplify surveillance programs, since they reduce time, labour, and variability within analysis. In the present work, we developed a multiplex bead-based assay for the detection of specific antibodies to six relevant pathogens affecting swine: ASFV, CSFV, PRRSV, SIV, TB and HEV. The most immunogenic target antigen of each pathogen was selected as the target protein to coat different microsphere regions in order to develop this multiplex assay. A total of 1544 serum samples from experimental infections as well as field samples were included in the analysis. The 6-plex assay exhibited credible diagnostic parameters with sensitivities ranging from 87.0% to 97.5% and specificities ranging from 87.9% to 100.0%, demonstrating it to be a potential high throughput tool for surveillance of infectious diseases in swine.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Vírus da Síndrome Respiratória e Reprodutiva Suína , Doenças dos Suínos , Febre Suína Africana/diagnóstico , Animais , Humanos , Sensibilidade e Especificidade , Suínos , Doenças dos Suínos/diagnóstico
18.
Transbound Emerg Dis ; 69(3): 1307-1318, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33794070

RESUMO

Rift Valley fever phlebovirus (RVFV) is an arthropod-borne virus that can cause severe disease in ruminants and humans. Epidemics occur mainly after heavy rainfall, which leads to a significant increase in the occurrence of RVFV-transmitting mosquitoes. During inter-epidemic periods, the virus is assumed to be maintained between mosquitoes, susceptible livestock and yet unknown wildlife. The widespread rodent Rattus rattus (black rat) has been suspected to be involved in RVFV maintenance. In order to elucidate its susceptibility and thus its possible role in the transmission cycle of the virus, an experimental infection study was performed. Black rats were subcutaneously infected with highly virulent RVFV strain 35/74 and euthanized on days 3, 14 and 28 post-infection. Additional black rats served as non-infected contact animals. The infected black rats showed high susceptibility to RVFV infection. Generation of RVFV-neutralizing antibodies was found, and the rats developed viraemias lasting up to 17 days. Viral RNA was found in tissues until the last day of the experiment. However, neither a clinical manifestation nor virus-induced histopathological lesions were observed in any rat. These findings indicate the persistence of RVFV in black rats without affecting the animals. In contact animals, no evidence of horizontal RVFV transmission was found, although the co-housed infected rats showed oral, rectal and conjunctival RVFV shedding. Results of this study point to an involvement of black rats in the RVFV transmission cycle, and further studies are needed to investigate their potential role in the maintenance of the virus.


Assuntos
Culicidae , Phlebovirus , Febre do Vale de Rift , Vírus da Febre do Vale do Rift , Doenças dos Roedores , Animais , Ratos , Replicação Viral
19.
Viruses ; 13(6)2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34205182

RESUMO

Hepatitis E is an emerging viral disease that is the leading cause of viral hepatitis in the world. The vast majority of hepatitis E cases in developed countries are caused by zoonotic genotypes 3 and 4 of hepatitis E virus (HEV) for which pig and wild boar and to lesser extent rabbits are the main reservoir. According to recent reports rabbits are a source of human HEV infection and highlight the risk of zoonotic foodborne transmission. Here we report the molecular analysis of a novel HEV strain identified in a rabbit during a countrywide surveillance of rabbits and hares in Germany, 2016. The analysis of the complete genome reveals characteristics of a putative novel recombinant subtype of the species Orthohepevirus A within the clade of genotype 3 but not closely related to any known subtypes. Importantly, the genome of this strain possesses a nucleotide exchange in the overlapping region of open reading frames ORF2/ORF3 interfering with a broadly applied diagnostic real-time RT-PCR. In conclusion, a new type of HEV strain was identified in a German rabbit with atypical and novel sequence characteristics.


Assuntos
Genótipo , Lebres/virologia , Vírus da Hepatite E/classificação , Vírus da Hepatite E/genética , Hepatite E/veterinária , Zoonoses/virologia , Animais , Genoma Viral , Alemanha/epidemiologia , Hepatite E/epidemiologia , Vírus da Hepatite E/isolamento & purificação , Fases de Leitura Aberta , Filogenia , RNA Viral/genética , Coelhos , Análise de Sequência de DNA , Zoonoses/epidemiologia
20.
Pathogens ; 10(6)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34072763

RESUMO

Rift Valley fever phlebovirus (RVFV) is a zoonotic arthropod-borne virus, which has led to devastating epidemics in African countries and on the Arabian Peninsula. Results of in-vivo, in-vitro and field studies suggested that amphibians and reptiles may play a role as reservoir hosts of RVFV, promoting its maintenance during inter-epidemic periods. To elucidate this hypothesis, we examined two newly established reptile-derived cell lines (Egyptian cobra and Chinese pond turtle) and five previously generated reptile- and amphibian-derived cell lines for their replicative capacity for three low- and high-pathogenic RVFV strains. At different time points after infection, viral loads (TCID50), genome loads and the presence of intracellular viral antigen (immunofluorescence) were assessed. Additionally, the influence of temperatures on the replication was examined. Except for one cell line (read-eared slider), all seven cell lines were infected by all three RVFV strains. Two different terrapin-derived cell lines (Common box turtle, Chinese pond turtle) were highly susceptible. A temperature-dependent replication of RVFV was detected for both amphibian and reptile cells. In conclusion, the results of this study indicate the general permissiveness of amphibian and reptile cell lines to RVFV and propose a potential involvement of terrapins in the virus ecology.

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