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1.
Viruses ; 16(4)2024 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-38675958

RESUMO

Reverse zoonotic transmission events of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been described since the start of the pandemic, and the World Organisation for Animal Health (WOAH) designated the detection of SARS-CoV-2 in animals a reportable disease. Eighteen domestic and zoo animals in Great Britain and Jersey were tested by APHA for SARS-CoV-2 during 2020-2023. One domestic cat (Felis catus), three domestic dogs (Canis lupus familiaris), and three Amur tigers (Panthera tigris altaica) from a zoo were confirmed positive during 2020-2021 and reported to the WOAH. All seven positive animals were linked with known SARS-CoV-2 positive human contacts. Characterisation of the SARS-CoV-2 variants by genome sequencing indicated that the cat was infected with an early SARS-CoV-2 lineage. The three dogs and three tigers were infected with the SARS-CoV-2 Delta variant of concern (B.1.617.2). The role of non-human species in the onward transmission and emergence of new variants of SARS-CoV-2 remain poorly defined. Continued surveillance of SARS-CoV-2 in relevant domestic and captive animal species with high levels of human contact is important to monitor transmission at the human-animal interface and to assess their role as potential animal reservoirs.


Assuntos
Animais de Zoológico , COVID-19 , SARS-CoV-2 , Tigres , Animais , Cães , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/classificação , COVID-19/transmissão , COVID-19/epidemiologia , COVID-19/veterinária , COVID-19/virologia , Tigres/virologia , Gatos , Animais de Zoológico/virologia , Inglaterra/epidemiologia , Humanos , Filogenia , Doenças do Cão/virologia , Doenças do Cão/epidemiologia , Doenças do Cão/transmissão , Zoonoses/virologia , Zoonoses/transmissão , Zoonoses/epidemiologia
2.
Vaccine ; 41(44): 6565-6571, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37716829

RESUMO

Many rabies endemic-countries have recognized rabies as a public health problem that can be eliminated. As a result, some countries have started implementing small-scale vaccination programs with the aim of scaling them up. Post-vaccination serological monitoring is crucial to assess the efficacy of these programs. The recommended serological tests, the rapid fluorescent focus inhibition test, and the fluorescent antibody virus neutralization (FAVN) are accurate; however, the procedures require considerable expertise and must be carried out in high containment facilities, which are often not available in rabies endemic countries. Given these constraints, enzyme linked immunosorbent assays (ELISAs) have been considered as alternative methods to neutralization tests. This is the first study to evaluate, under field conditions, the performance of the commercial rabies indirect-ELISA (iELISA), the PlateliaTM Rabies II kit ad usum Veterinarium kit, using sera from domestic dogs. Serum samples were collected from two groups of community dogs in northern Tanzania: i) dogs with no history of vaccination against rabies (n = 100) and ii) dogs vaccinated with the Nobivac Canine Rabies® vaccine (n = 101) four weeks previously. When compared to the gold standard FAVN test, the iELISA was found to be 99% specific and 98% sensitive and there was a significant correlation between the two tests (p < 0.001, r = 0.92). Given these findings, we conclude that the PlateliaTM Rabies II kit ad usum Veterinarium can be considered a valuable tool for the rapid assessment of vaccination status of animals in vaccination programs.


Assuntos
Doenças do Cão , Vacina Antirrábica , Vírus da Raiva , Raiva , Animais , Cães , Raiva/diagnóstico , Raiva/prevenção & controle , Raiva/veterinária , Anticorpos Antivirais , Sensibilidade e Especificidade , Ensaio de Imunoadsorção Enzimática/métodos , Fatores Imunológicos , Vacinação , Doenças do Cão/diagnóstico , Doenças do Cão/prevenção & controle
3.
J Virol Methods ; 319: 114769, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37391076

RESUMO

Rabies virus (RABV) causes a fatal encephalitis that can be prevented through timely vaccination. The levels of virus neutralising antibodies against rabies virus induced by vaccination can be measured using the fluorescent antibody virus neutralisation (FAVN) test. Following incubation of live virus with sera, this method involves the fixation of cell monolayers and staining of rabies virus-specific antigen using fluorescein isothiocyanate (FITC) -conjugated antibody to enable visualisation of rabies virus antigen using a fluorescence microscope. To simplify this procedure, a fluorescent recombinant rabies virus was constructed using reverse genetics by inserting the gene for the mCherry fluorescent protein in front of the ribonucleoprotein gene of the SAD B-19 genome and replacing its glycoprotein with that of the Challenge Virus Standard (CVS)-11 RABV strain to ensure antigenic authenticity with the FAVN. This new recombinant virus (termed mCCCG) expressed the mCherry protein to high levels enabling direct observation of infected cells. In vitro growth kinetics of mCCCG were indistinguishable from that of CVS-11. The stability of the recombinant virus was assessed by sequencing several passages of the rescued virus and only minor changes were detected. Comparative assessment of the virus neutralisation test using mCherry producing virus (NTmCV) against the FAVN demonstrated that test results were equivalent to each other; therefore, mCCCG can be used as an alternative to CVS-11 for measuring antibody titres against the rabies virus. The use of NTmCV removes the need for expensive antibody conjugates and significantly reduces assay time. This would be particularly beneficial for RABV serological assessment in resource limited settings. Moreover, the reading of the plates can be automatically using a cell imaging reader.


Assuntos
Vacina Antirrábica , Vírus da Raiva , Raiva , Humanos , Vírus da Raiva/genética , Anticorpos Antivirais , Testes de Neutralização/métodos , Antígenos Virais , Anticorpos Neutralizantes
4.
J Extracell Vesicles ; 11(11): e12247, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36377074

RESUMO

Vaccine platforms enable fast development, testing, and manufacture of more affordable vaccines. Here, we evaluated Generalized Modules for Membrane Antigens (GMMA), outer membrane vesicles (OMVs) generated by genetically modified Gram-negative bacteria, as a vaccine platform for viral pathogens. Influenza A virus hemagglutinin (HA), either physically mixed with GMMA (HA+STmGMMA mix), or covalently linked to GMMA surface (HA-STmGMMA conjugate), significantly increased antigen-specific humoral and cellular responses, with HA-STmGMMA conjugate inducing further enhancement than HA+STmGMMA mix. HA-STmGMMA conjugate protected mice from lethal challenge. The versatility for this platform was confirmed by conjugation of rabies glycoprotein (RABVG) onto GMMA through the same method. RABVG+STmGMMA mix and RABVG-STmGMMA conjugate exhibited similar humoral and cellular response patterns and protection efficacy as the HA formulations, indicating relatively consistent responses for different vaccines based on the GMMA platform. Comparing to soluble protein, GMMA was more efficiently taken up in vivo and exhibited a B-cell preferential uptake in the draining lymph nodes (LNs). Together, GMMA enhances immunity against viral antigens, and the platform works well with different antigens while retaining similar immunomodulatory patterns. The findings of our study imply the great potential of GMMA-based vaccine platform also against viral infectious diseases.


Assuntos
Antígenos Virais , Vacinas , Camundongos , Animais , Membranas
5.
Sci Rep ; 12(1): 10298, 2022 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-35717348

RESUMO

Following the first detection in the United Kingdom of Usutu virus (USUV) in wild birds in 2020, we undertook a multidisciplinary investigation that combined screening host and vector populations with interrogation of national citizen science monitoring datasets to assess the potential for population impacts on avian hosts. Pathological findings from six USUV-positive wild passerines were non-specific, highlighting the need for molecular and immunohistochemical examinations to confirm infection. Mosquito surveillance at the index site identified USUV RNA in Culex pipiens s.l. following the outbreak. Although the Eurasian blackbird (Turdus merula) is most frequently impacted by USUV in Europe, national syndromic surveillance failed to detect any increase in occurrence of clinical signs consistent with USUV infection in this species. Furthermore, there was no increase in recoveries of dead blackbirds marked by the national ringing scheme. However, there was regional clustering of blackbird disease incident reports centred near the index site in 2020 and a contemporaneous marked reduction in the frequency with which blackbirds were recorded in gardens in this area, consistent with a hypothesis of disease-mediated population decline. Combining results from multidisciplinary schemes, as we have done, in real-time offers a model for the detection and impact assessment of future disease emergence events.


Assuntos
Doenças das Aves , Infecções por Flavivirus , Flavivirus , Aves Canoras , Animais , Surtos de Doenças/veterinária , Flavivirus/genética , Infecções por Flavivirus/epidemiologia , Infecções por Flavivirus/veterinária , Mosquitos Vetores , Reino Unido/epidemiologia
6.
J Med Microbiol ; 71(5)2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35604835

RESUMO

Louping ill virus (LIV) is a single-stranded, positive-sense RNA virus within the genus Flavivirus that is transmitted to vertebrate hosts by bites from infected ticks, the arthropod vector. The virus affects livestock in upland areas of Great Britain and Ireland, resulting in a febrile illness that can progress to fatal encephalitis. Prevention of the disease is facilitated by combining acaricide treatment, land management and vaccination strategies. However, vaccines have been discontinued in recent years. Although rare, LIV can be transmitted to and cause disease in humans. Consequently, LIV infection is a threat to human and veterinary health and can impact on the rural economy.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos , Carrapatos , Animais , Vírus da Encefalite Transmitidos por Carrapatos/genética , Humanos , Reino Unido
7.
Viruses ; 13(12)2021 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-34960647

RESUMO

Lagos bat lyssavirus (LBV) comprising four lineages (A, B, C and D) can potentially cause the fatal disease rabies. Although LBV-B was initially isolated in Nigeria in 1956, there is no information on LBV lineages circulating in Nigeria. This study was undertaken for the first time to measure the neutralizing antibodies against four lineages of LBVs in straw-colored fruit bats (Eidolon helvum) in Makurdi, Nigeria. Serum samples (n = 180) collected during two periods (November 2017-March 2018 and November 2018-March 2019) from terminally bled bats captured for human consumption were tested using a modified fluorescent antibody virus neutralization (mFAVN) assay. A high proportion of bat sera (74%) neutralized at least one lineage of LBV (with reciprocal titers from 9 to >420.89) and most of them neutralized LBV-A (63%), followed by LBV-D (49%), LBV-C (45%) and LBV-B (24%). The majority of positive sera (75%, n = 100) neutralized multiple LBV lineages while the remaining 25% (n = 33) neutralized only a single lineage, i.e., LBV-A (n = 23), LBV-D (n = 8) and LBV-C (n = 2). None exclusively neutralized LBV-B. The results suggest that exposure to LBV is common in E. helvum and that LBV-A (but not LBV-B) is likely to be circulating in this region of Nigeria.


Assuntos
Anticorpos Antivirais/sangue , Quirópteros/virologia , Lyssavirus/imunologia , Raiva/virologia , Infecções por Rhabdoviridae/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Humanos , Lyssavirus/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Nigéria/epidemiologia
8.
Parasit Vectors ; 14(1): 566, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34732254

RESUMO

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.


Assuntos
Vírus Bunyamwera/fisiologia , Culicidae/virologia , Mosquitos Vetores/virologia , Animais , Vírus Bunyamwera/genética , Infecções por Bunyaviridae/transmissão , Infecções por Bunyaviridae/virologia , Culicidae/imunologia , Europa (Continente) , Feminino , Humanos , Masculino , Mosquitos Vetores/imunologia , Saliva/virologia
9.
Front Vet Sci ; 8: 728271, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660765

RESUMO

Background: Thermostable vaccines greatly improved the reach and impact of large-scale programmes to eliminate infectious diseases such as smallpox, polio, and rinderpest. A study from 2015 demonstrated that the potency of the Nobivac® Rabies vaccine was not impacted following experimental storage at 30°C for 3 months. Whether the vaccine would remain efficacious following storage under more natural, fluctuating temperature conditions remains unknown. We carried out a randomised controlled non-inferiority trial to compare serological responses in dogs following vaccination with doses stored under cold chain conditions with those stored within a locally made Passive Cooling Device ("Zeepot") under fluctuating temperature conditions. Materials and Methods: Nobivac® Rabies vaccine was stored under either cold-chain conditions or within the Zeepot for 2 months. Daily ambient temperatures and temperatures within the Zeepot were recorded every 3 h. Following storage, 412 domestic dogs were randomly assigned to receive either cold-chain or Zeepot stored Nobivac® Rabies vaccine. Baseline and day 28-post vaccination blood samples were collected. Serological analysis using the Fluorescent Antibody Virus Neutralisation assay was carried out with a threshold of 0.5 IU/ml to determine seroconversion. In addition, the impact of dog Body Condition Score, sex, and age on seroconversion was examined. Results: The serological response of dogs vaccinated using Nobivac® Rabies vaccine stored within the Zeepot was not inferior to the response of dogs vaccinated using cold-chain stored vaccine (z = 1.1, df = 313, p-value = 0.25). Indeed, the 28-day post-vaccination group geometric mean titre was 1.8 and 2.0 IU/ml for cold-chain vs. non-cold-chain storage, respectively. Moreover, the percentage of dogs that seroconverted in each arm was almost identical (85%). There was a positive linear trend between Body Condition Score (O.R. 2.2, 95% CI: 1.1-5.1) and seroconversion, suggesting dogs of poor condition may not respond as expected to vaccination. Conclusions: Our study demonstrated the potency of Nobivac® Rabies vaccine is not impacted following storage under elevated fluctuating temperatures within a Zeepot. These results have potentially exciting applications for scaling up mass dog vaccination programmes in low-and-middle income countries, particularly for hard-to-reach populations with limited access to power and cold-chain vaccine storage.

10.
Viruses ; 13(10)2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34696409

RESUMO

Lyssaviruses are an important genus of zoonotic viruses which cause the disease rabies. The United Kingdom is free of classical rabies (RABV). However, bat rabies due to European bat lyssavirus 2 (EBLV-2), has been detected in Daubenton's bats (Myotis daubentonii) in Great Britain since 1996, including a fatal human case in Scotland in 2002. Across Europe, European bat lyssavirus 1 (EBLV-1) is commonly associated with serotine bats (Eptesicus serotinus). Despite the presence of serotine bats across large parts of southern England, EBLV-1 had not previously been detected in this population. However, in 2018, EBLV-1 was detected through passive surveillance in a serotine bat from Dorset, England, using a combination of fluorescent antibody test, reverse transcription-PCR, Sanger sequencing and immunohistochemical analysis. Subsequent EBLV-1 positive serotine bats have been identified in South West England, again through passive surveillance, during 2018, 2019 and 2020. Here, we confirm details of seven cases of EBLV-1 and present similarities in genetic sequence indicating that emergence of EBLV-1 is likely to be recent, potentially associated with the natural movement of bats from the near continent.


Assuntos
Quirópteros/virologia , Lyssavirus/patogenicidade , Animais , Lyssavirus/genética , Raiva/virologia , Infecções por Rhabdoviridae/epidemiologia , Infecções por Rhabdoviridae/virologia , Reino Unido/epidemiologia
11.
Viruses ; 13(9)2021 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-34578350

RESUMO

Pathogen discovery contributes to our knowledge of bat-borne viruses and is linked to the heightened interest globally in bats as recognised reservoirs of zoonotic agents. The transmission of lyssaviruses from bats-to-humans, domestic animals, or other wildlife species is uncommon, but interest in these pathogens remains due to their ability to cause an acute, progressive, invariably fatal encephalitis in humans. Consequently, the detection and characterisation of bat lyssaviruses continues to expand our knowledge of their phylogroup definition, viral diversity, host species association, geographical distribution, evolution, mechanisms for perpetuation, and the potential routes of transmission. Although the opportunity for lyssavirus cross-species transmission seems rare, adaptation in a new host and the possibility of onward transmission to humans requires continued investigation. Considering the limited efficacy of available rabies biologicals it is important to further our understanding of protective immunity to minimize the threat from these pathogens to public health. Hence, in addition to increased surveillance, the development of a niche pan-lyssavirus vaccine or therapeutic biologics for post-exposure prophylaxis for use against genetically divergent lyssaviruses should be an international priority as these emerging lyssaviruses remain a concern for global public health.


Assuntos
Saúde Pública , Infecções por Rhabdoviridae/terapia , Animais , Quirópteros/virologia , Encefalite/terapia , Encefalite/virologia , Humanos , Itália , Lyssavirus/classificação , Raiva , Infecções por Rhabdoviridae/epidemiologia , Infecções por Rhabdoviridae/virologia , Zoonoses/virologia
12.
PLoS Negl Trop Dis ; 15(5): e0009431, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34014930

RESUMO

Human fatalities caused by rabies are rarely reported in Jordan; however, domestic animals are more likely to fall victim to rabies compared to wild animals, at least this is the case in Jordan due to the presence of canine rabies. In this study, twelve brain samples from domestic and wild animals suspected of being infected with rabies virus from different regions of Jordan were collected during 2019. Seven of them tested positive using the fluorescent antibody test and real-time SYBR RT-PCR assay. Five specimens were from stray dogs and two from foxes. The whole genome sequences were obtained from the positive samples. Sequence analysis showed that one dog virus from Al Quwaysimah city located in Amman governorate, was closely related to an Israeli strain belonging to a Cosmopolitan ME1a clade. The genomes of the remaining six viruses (four from dogs and two from foxes) collected from different areas of Jordan were genetically-related to each other and clustered together with sequences from Iran and Turkey; all belong to Cosmopolitan ME2 clade. These sequences were analyzed with six other Jordanian rabies virus nucleoprotein (N) gene sequences available in the public database, five of them belong to ME1a clade and one belongs to ME1b clade. Rabies virus whole genome data is scarce across the Middle East. This study provides a better understanding of the molecular epidemiology of rabies virus in the region.


Assuntos
Doenças do Cão/epidemiologia , Vírus da Raiva/genética , Raiva/veterinária , Animais , Encéfalo/virologia , Doenças do Cão/virologia , Cães , Raposas/virologia , Jordânia/epidemiologia , Epidemiologia Molecular , Filogenia , Raiva/epidemiologia , Vírus da Raiva/classificação , Sequenciamento Completo do Genoma
13.
Viruses ; 13(4)2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33924168

RESUMO

SARS-CoV-2 virus was first detected in late 2019 and circulated globally, causing COVID-19, which is characterised by sub-clinical to severe disease in humans. Here, we investigate the serological antibody responses to SARS-CoV-2 infection during acute and convalescent infection using a cohort of (i) COVID-19 patients admitted to hospital, (ii) healthy individuals who had experienced 'COVID-19 like-illness', and (iii) a cohort of healthy individuals prior to the emergence of SARS-CoV-2. We compare SARS-CoV-2 specific antibody detection rates from four different serological methods, virus neutralisation test (VNT), ID Screen® SARS-CoV-2-N IgG ELISA, Whole Antigen ELISA, and lentivirus-based SARS-CoV-2 pseudotype virus neutralisation tests (pVNT). All methods were able to detect prior infection with COVID-19, albeit with different relative sensitivities. The VNT and SARS-CoV-2-N ELISA methods showed a strong correlation yet provided increased detection rates when used in combination. A pVNT correlated strongly with SARS-CoV-2 VNT and was able to effectively discriminate SARS-CoV-2 antibody positive and negative serum with the same efficiency as the VNT. Moreover, the pVNT was performed with the same level of discrimination across multiple separate institutions. Therefore, the pVNT is a sensitive, specific, and reproducible lower biosafety level alternative to VNT for detecting SARS-CoV-2 antibodies for diagnostic and research applications. Our data illustrate the potential utility of applying VNT or pVNT and ELISA antibody tests in parallel to enhance the sensitivity of exposure to infection.


Assuntos
Anticorpos Antivirais/sangue , Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , SARS-CoV-2/imunologia , Idoso , Anticorpos Neutralizantes/sangue , COVID-19/sangue , COVID-19/imunologia , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Lentivirus/genética , Masculino , Pessoa de Meia-Idade , Testes de Neutralização , Reprodutibilidade dos Testes , SARS-CoV-2/isolamento & purificação , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia
14.
Viruses ; 12(12)2020 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-33316899

RESUMO

Emerging infectious diseases are of great concern to public health, as highlighted by the ongoing coronavirus disease 2019 (COVID-19) pandemic. Such diseases are of particular danger during mass gathering and mass influx events, as large crowds of people in close proximity to each other creates optimal opportunities for disease transmission. The Hashemite Kingdom of Jordan and the Kingdom of Saudi Arabia are two countries that have witnessed mass gatherings due to the arrival of Syrian refugees and the annual Hajj season. The mass migration of people not only brings exotic diseases to these regions but also brings new diseases back to their own countries, e.g., the outbreak of MERS in South Korea. Many emerging pathogens originate in bats, and more than 30 bat species have been identified in these two countries. Some of those bat species are known to carry viruses that cause deadly diseases in other parts of the world, such as the rabies virus and coronaviruses. However, little is known about bats and the pathogens they carry in Jordan and Saudi Arabia. Here, the importance of enhanced surveillance of bat-borne infections in Jordan and Saudi Arabia is emphasized, promoting the awareness of bat-borne diseases among the general public and building up infrastructure and capability to fill the gaps in public health preparedness to prevent future pandemics.


Assuntos
Quirópteros/virologia , Doenças Transmissíveis Emergentes/epidemiologia , Coronavirus/isolamento & purificação , Saúde Pública , Zoonoses/epidemiologia , Animais , COVID-19 , Doenças Transmissíveis Emergentes/virologia , Coronavirus/classificação , Coronavirus/patogenicidade , Surtos de Doenças/prevenção & controle , Humanos , Jordânia , Arábia Saudita , Zoonoses/transmissão , Zoonoses/virologia
15.
Parasit Vectors ; 13(1): 596, 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33243297

RESUMO

BACKGROUND: West Nile virus (WNV) is a single-stranded RNA virus that can cause neurological disease in both humans and horses. Due to the movement of competent vectors and viraemic hosts, WNV has repeatedly emerged globally and more recently in western Europe. Within the UK, WNV is a notifiable disease in horses, and vaccines against the virus are commercially available. However, there has been no investigation into the seroprevalence of WNV in the UK equine population to determine the extent of vaccination or to provide evidence of recent infection. METHODS: Equine serum samples were obtained from the Animal and Plant Health Agency's equine testing service between August and November 2019. A total of 988 serum samples were selected for horses resident in South East England. WNV seroprevalence was determined using two enzyme-linked immunosorbent assays (ELISAs) to detect total flavivirus antibodies and WNV-specific immunoglobulin M (IgM) antibodies. Positive IgM results were investigated by contacting the submitting veterinarian to establish the clinical history or evidence of prior vaccination of the horses in question. RESULTS: Within the cohort, 274 samples tested positive for flavivirus antibodies, of which two subsequently tested positive for WNV-specific IgM antibodies. The follow-up investigation established that both horses had been vaccinated prior to serum samples being drawn, which resulted in an IgM-positive response. All the samples that tested positive by competition ELISA were from horses set to be exported to countries where WNV is endemic. Consequently, the positive results were likely due to previous vaccination. In contrast, 714 samples were seronegative, indicating that the majority of the UK equine population may be susceptible to WNV infection. CONCLUSIONS: There was no evidence for cryptic WNV infection in a cohort of horses sampled in England in 2019. All IgM-seropositive cases were due to vaccination; this should be noted for future epidemiological surveys in the event of a disease outbreak, as it is not possible to distinguish vaccinated from infected horses without knowledge of their clinical histories.


Assuntos
Anticorpos Antivirais/sangue , Doenças dos Cavalos/sangue , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/imunologia , Animais , Estudos de Coortes , Doenças dos Cavalos/epidemiologia , Doenças dos Cavalos/virologia , Cavalos , Imunoglobulina G/sangue , Estudos Soroepidemiológicos , Reino Unido , Febre do Nilo Ocidental/sangue , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/genética , Vírus do Nilo Ocidental/isolamento & purificação
16.
Euro Surveill ; 25(41)2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33063656

RESUMO

In August 2020, as part of a long-term disease surveillance programme, Usutu virus was detected in five Eurasian blackbirds (Turdus merula) and one house sparrow (Passer domesticus) from Greater London, England. This was initially detected by reverse transcription-PCR and was confirmed by virus isolation and by immunohistochemical detection of flavivirus in tissues. Phylogenetic analysis identified Usutu virus African 3.2 lineage, which is prevalent in the Netherlands and Belgium, suggesting a potential incursion from mainland Europe.


Assuntos
Doenças das Aves/epidemiologia , Surtos de Doenças , Flavivirus/isolamento & purificação , Vigilância de Evento Sentinela/veterinária , Animais , Animais Selvagens , Aves , Flavivirus/genética , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência , Reino Unido/epidemiologia
17.
Viruses ; 12(4)2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32230744

RESUMO

In South Africa, canid rabies virus (RABV) infection is maintained in domestic and wildlife species. The identification of rabies in African civets raised the question of whether this wildlife carnivore is a potential reservoir host of RABVs of direct and ancestral dog origin (dog-maintained and dog-derived origins) with an independent cycle of transmission. Genetic analyses of African civet nucleoprotein sequences for 23 African civet RABVs and historically published sequences demonstrated that RABVs from African civets have two origins related to dog and mongoose rabies enzootics. The data support observations of the interaction of civets with domestic dogs and wildlife mongooses, mostly in Northern South Africa and North-East Zimbabwe. Within each host species clade, African civet RABVs group exclusively together, implying intra-species virus transfer occurs readily. The canid RABV clade appears to support virus transfer more readily between hosts than mongoose RABVs. Furthermore, these data probably indicate short transmission chains with conspecifics that may be related to transient rabies maintenance in African civets. Hence, it is important to continue monitoring the emergence of lyssaviruses in this host. Observations from this study are supported by ongoing and independent similar cases, in which bat-eared foxes and black-backed jackal species maintain independent rabies cycles of what were once dog-maintained RABVs.


Assuntos
Lyssavirus , Raiva/epidemiologia , Raiva/virologia , Viverridae/virologia , Animais , Animais Selvagens/virologia , Reservatórios de Doenças/virologia , Sequenciamento de Nucleotídeos em Larga Escala , Interações Hospedeiro-Patógeno , Lyssavirus/classificação , Lyssavirus/genética , Filogenia , RNA Viral
18.
Sci Rep ; 10(1): 1740, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-32015375

RESUMO

Many high-consequence human and animal pathogens persist in wildlife reservoirs. An understanding of the dynamics of these pathogens in their reservoir hosts is crucial to inform the risk of spill-over events, yet our understanding of these dynamics is frequently insufficient. Viral persistence in a wild bat population was investigated by combining empirical data and in-silico analyses to test hypotheses on mechanisms for viral persistence. A fatal zoonotic virus, European Bat lyssavirus type 2 (EBLV-2), in Daubenton's bats (Myotis daubentonii) was used as a model system. A total of 1839 M. daubentonii were sampled for evidence of virus exposure and excretion during a prospective nine year serial cross-sectional survey. Multivariable statistical models demonstrated age-related differences in seroprevalence, with significant variation in seropositivity over time and among roosts. An Approximate Bayesian Computation approach was used to model the infection dynamics incorporating the known host ecology. The results demonstrate that EBLV-2 is endemic in the study population, and suggest that mixing between roosts during seasonal swarming events is necessary to maintain EBLV-2 in the population. These findings contribute to understanding how bat viruses can persist despite low prevalence of infection, and why infection is constrained to certain bat species in multispecies roosts and ecosystems.


Assuntos
Comportamento Animal/fisiologia , Quirópteros/virologia , Lyssavirus/fisiologia , Infecções por Rhabdoviridae/transmissão , Animais , Estudos Transversais , Modelos Estatísticos , Estudos Soroepidemiológicos
19.
Trop Med Infect Dis ; 5(1)2020 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-31963635

RESUMO

As a neglected zoonotic disease, rabies causes approximately 5.9 × 104 human deaths annually, primarily affecting low- and middle-income countries in Asia and Africa. In those regions, insufficient surveillance is hampering adequate medical intervention and is driving the vicious cycle of neglect. Where resources to provide laboratory disease confirmation are limited, there is a need for user-friendly and low-cost reliable diagnostic tools that do not rely on specialized laboratory facilities. Lateral flow devices (LFD) offer an alternative to conventional diagnostic methods and may strengthen control efforts in low-resource settings. Five different commercially available LFDs were compared in a multi-centered study with respect to their diagnostic sensitivity and their agreement with standard rabies diagnostic techniques. Our evaluation was conducted by several international reference laboratories using a broad panel of samples. The overall sensitivities ranged from 0% up to 62%, depending on the LFD manufacturer, with substantial variation between the different laboratories. Samples with high antigen content and high relative viral load tended to test positive more often in the Anigen/Bionote test, the latter being the one with the best performance. Still, the overall unsatisfactory findings corroborate a previous study and indicate a persistent lack of appropriate test validation and quality control. At present, the tested kits are not suitable for in-field use for rabies diagnosis, especially not for suspect animals where human contact has been identified, as an incorrect negative diagnosis may result in human casualties. This study points out the discrepancy between the enormous need for such a diagnostic tool on the one hand, and on the other hand, a number of already existing tests that are not yet ready for use.

20.
Microbiol Resour Announc ; 8(41)2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601661

RESUMO

Here, we report the first complete genome of a bovine ephemeral fever virus (BEFV) isolate from an infected bovine in Israel. The genome shares 95.3% identity with a Turkish genomic sequence but contains α3 and γ open reading frames that are truncated compared to those of existing BEFV genome sequences.

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