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1.
Euro Surveill ; 25(11)2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32209164

RESUMO

Data concerning the transmission of the novel severe acute respiratory syndrome coronavirus (SARS-CoV-2) in paucisymptomatic patients are lacking. We report an Italian paucisymptomatic case of coronavirus disease 2019 with multiple biological samples positive for SARS-CoV-2. This case was detected using the World Health Organization protocol on cases and contact investigation. Current discharge criteria and the impact of extra-pulmonary SARS-CoV-2 samples are discussed.


Assuntos
Infecções Assintomáticas , Infecções por Coronavirus/diagnóstico , Coronavirus/isolamento & purificação , Fezes/virologia , Pulmão/diagnóstico por imagem , Nasofaringe/virologia , Pneumonia Viral/diagnóstico , Viagem , Eliminação de Partículas Virais , Anticorpos Antivirais/imunologia , Betacoronavirus , China , Busca de Comunicante , Coronavirus/genética , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Humanos , Itália , Pulmão/patologia , Masculino , Pandemias , Pneumonia Viral/terapia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Quarentena , Radiografia Torácica , Reação em Cadeia da Polimerase em Tempo Real , Tomografia Computadorizada por Raios X , Organização Mundial da Saúde , Adulto Jovem
2.
Emerg Microbes Infect ; 9(1): 651-663, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32192415

RESUMO

Equine parvovirus-hepatitis (EqPV-H) has recently been associated with cases of Theiler's disease, a form of fulminant hepatic necrosis in horses. To assess whether EqPV-H is the cause of Theiler's disease, we first demonstrated hepatotropism by PCR on tissues from acutely infected horses. We then experimentally inoculated horses with EqPV-H and 8 of 10 horses developed hepatitis. One horse showed clinical signs of liver failure. The onset of hepatitis was temporally associated with seroconversion and a decline in viremia. Liver histology and in situ hybridization showed lymphocytic infiltrates and necrotic EqPV-H-infected hepatocytes. We next investigated potential modes of transmission. Iatrogenic transmission via allogeneic stem cell therapy for orthopedic injuries was previously suggested in a case series of Theiler's disease, and was demonstrated here for the first time. Vertical transmission and mechanical vectoring by horse fly bites could not be demonstrated in this study, potentially due to limited sample size. We found EqPV-H shedding in oral and nasal secretions, and in feces. Importantly, we could demonstrate EqPV-H transmission via oral inoculation with viremic serum. Together, our findings provide additional information that EqPV-H is the likely cause of Theiler's disease and that transmission of EqPV-H occurs via both iatrogenic and natural routes.


Assuntos
Hepatite Viral Animal/virologia , Doenças dos Cavalos/virologia , Fígado/virologia , Infecções por Parvoviridae/veterinária , Parvovirus/fisiologia , Animais , Dípteros/virologia , Fezes/virologia , Feminino , Hepatite Viral Animal/patologia , Hepatite Viral Animal/transmissão , Hepatócitos/patologia , Hepatócitos/virologia , Doenças dos Cavalos/patologia , Doenças dos Cavalos/transmissão , Cavalos , Transmissão Vertical de Doença Infecciosa , Insetos Vetores/virologia , Fígado/patologia , Linfócitos , Masculino , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/virologia , Boca/virologia , Necrose , Infecções por Parvoviridae/patologia , Infecções por Parvoviridae/transmissão , Infecções por Parvoviridae/virologia , Parvovirus/isolamento & purificação , Parvovirus/patogenicidade , Tropismo Viral , Viremia , Eliminação de Partículas Virais
3.
Emerg Microbes Infect ; 9(1): 386-389, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32065057

RESUMO

In December 2019, a novel coronavirus (2019-nCoV) caused an outbreak in Wuhan, China, and soon spread to other parts of the world. It was believed that 2019-nCoV was transmitted through respiratory tract and then induced pneumonia, thus molecular diagnosis based on oral swabs was used for confirmation of this disease. Likewise, patient will be released upon two times of negative detection from oral swabs. However, many coronaviruses can also be transmitted through oral-fecal route by infecting intestines. Whether 2019-nCoV infected patients also carry virus in other organs like intestine need to be tested. We conducted investigation on patients in a local hospital who were infected with this virus. We found the presence of 2019-nCoV in anal swabs and blood as well, and more anal swab positives than oral swab positives in a later stage of infection, suggesting shedding and thereby transmitted through oral-fecal route. We also showed serology test can improve detection positive rate thus should be used in future epidemiology. Our report provides a cautionary warning that 2019-nCoV may be shed through multiple routes.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/transmissão , Fezes/virologia , Pneumonia Viral/transmissão , Eliminação de Partículas Virais , China , Humanos
5.
Viruses ; 12(1)2020 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-31936476

RESUMO

Porcine deltacoronavirus (PDCoV) is a porcine enteropathogenic coronavirus that causes watery diarrhea, vomiting, and frequently death in piglets, causing serious economic losses to the pig industry. The strain CHN-JS-2017 was isolated and identified by cytopathology, immunofluorescence assays, transmission electron microscopy, and sequence analysis. A nucleotide sequence alignment showed that the whole genome of CHN-JS-2017 is 97.4%-99.6% identical to other PDCoV strains. The pathogenicity of the CHN-JS-2017 strain was investigated in orally inoculated five-day-old piglets; the piglets developed acute, watery diarrhea, but all recovered and survived. CHN-JS-2017 infection-induced microscopic lesions were observed, and viral antigens were detected mainly by immunohistochemical staining in the small intestine. The neonatal Fc receptor (FcRn) and polymeric immunoglobulin receptor (pIgR) are crucial immunoglobulin (Ig) receptors for the transcytosis ofimmunoglobulin G (IgG), IgA, or IgM. Importantly, CHN-JS-2017 infected five-day-old piglets could significantly down-regulate the expression of FcRn, pIgR, and nuclear factor-kappa B (NF-κB)in the intestinal mucosa. Note that the level of FcRn mRNA in the intestinal mucosa of normal piglets is positively correlated with pIgR and NF-κB. At the same time, the expressions of FcRn, pIgR, and NF-κB mRNA are also positively correlated in infected piglets. These results may help explain the immunological and pathological changes associated with porcine deltacorononirus infection.


Assuntos
Infecções por Coronavirus/veterinária , Coronavirus/classificação , Antígenos de Histocompatibilidade Classe I/imunologia , Mucosa Intestinal/imunologia , Receptores Fc/imunologia , Receptores de Imunoglobulina Polimérica/imunologia , Doenças dos Suínos/virologia , Animais , Antígenos Virais/análise , Coronavirus/isolamento & purificação , Infecções por Coronavirus/imunologia , Diarreia/veterinária , Diarreia/virologia , Regulação da Expressão Gênica , Mucosa Intestinal/virologia , Intestino Delgado/imunologia , Intestino Delgado/virologia , NF-kappa B/imunologia , Filogenia , RNA Viral/análise , Alinhamento de Sequência , Análise de Sequência de DNA , Suínos , Doenças dos Suínos/imunologia , Eliminação de Partículas Virais
6.
Emerg Microbes Infect ; 9(1): 20-31, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31859605

RESUMO

Porcine deltacoronavirus (PDCoV) is an emerging swine coronavirus that causes severe diarrhea, resulting in high mortality in neonatal piglets. Despite widespread outbreaks in many countries, no effective PDCoV vaccines are currently available. Here, we generated, for the first time, a full-length infectious cDNA clone of PDCoV. We further manipulated the infectious clone by replacing the NS6 gene with a green fluorescent protein (GFP) to generate rPDCoV-ΔNS6-GFP; likewise, rPDCoV-ΔNS7 was constructed by removing the ATG start codons of the NS7 gene. Growth kinetics studies suggest that rPDCoV-ΔNS7 could replicate similarly to that of the wild-type PDCoV, whereas rPDCoV-ΔNS6-GFP exhibited a substantial reduction of viral titer in vitro and in vivo. Piglets inoculated with rPDCoV-ΔNS7 or wild-type PDCoV showed similar diarrheic scores and pathological injury. In contrast, rPDCoV-ΔNS6-GFP-infected piglets did not show any clinical signs, indicating that the NS6 protein is an important virulence factor of PDCoV and that the NS6-deficient mutant virus might be a promising live-attenuated vaccine candidate. Taken together, the reverse genetics platform described here not only provides more insights into the role of PDCoV accessory proteins in viral replication and pathogenesis, but also allows the development of novel vaccines against PDCoV infection.


Assuntos
Infecções por Coronavirus/veterinária , Coronavirus/fisiologia , Doenças dos Suínos/virologia , Proteínas Virais Reguladoras e Acessórias/genética , Vacinas Virais/genética , Animais , Animais Recém-Nascidos , Doenças Transmissíveis Emergentes/imunologia , Doenças Transmissíveis Emergentes/patologia , Doenças Transmissíveis Emergentes/veterinária , Doenças Transmissíveis Emergentes/virologia , Coronavirus/classificação , Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Citocinas/imunologia , DNA Complementar , Genoma Viral , Genética Reversa , Sus scrofa , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/patologia , Replicação Viral , Eliminação de Partículas Virais
7.
PLoS One ; 14(12): e0226320, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31846475

RESUMO

BACKGROUND: Genital herpes simplex infection affects more than 500 million people worldwide. We have previously shown that COR-1, a therapeutic HSV-2 polynucleotide vaccine candidate, is safe and well tolerated in healthy subjects. OBJECTIVE: Here, we present a single center double-blind placebo-controlled, randomized phase I/IIa trial of COR-1 in HSV-2 positive subjects in which we assessed safety and tolerability as primary endpoints, and immunogenicity and therapeutic efficacy as exploratory endpoints. METHODS: Forty-four HSV-2+ subjects confirmed by positive serology or pathology, and positive qPCR during baseline shedding, with a recurrent genital HSV-2 history of at least 12 months including three to nine reported lesions in 12 months prior to screening, aged 18 to 50 years females and males with given written informed consent, were randomized into two groups. Three immunizations at 4-week intervals and one booster immunization at 6 months, each of 1 mg COR-1 DNA or placebo, were administered intradermally as two injections of 500 µg each to either one forearm or both forearms. RESULTS: No serious adverse events, life-threatening events or deaths occurred throughout the study. As expected, HSV-2 infected subjects displayed gD2-specific antibody titers prior to immunization. COR-1 was associated with a reduction in viral shedding after booster administration compared with baseline. CONCLUSIONS: This study confirms the previously demonstrated safety of COR-1 in humans and indicates a potential for use of COR-1 as a therapy to reduce viral shedding in HSV-2 infected subjects.


Assuntos
Herpes Genital/prevenção & controle , Herpesvirus Humano 2/imunologia , Herpesvirus Humano 2/fisiologia , Imunoterapia/métodos , Polinucleotídeos/imunologia , Adolescente , Adulto , Formação de Célula em Célula , Surtos de Doenças/prevenção & controle , Método Duplo-Cego , Feminino , Herpes Genital/epidemiologia , Herpes Genital/imunologia , Humanos , Imunidade Celular/imunologia , Imunidade Humoral , Imunoterapia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Segurança , Vacinas Virais/imunologia , Eliminação de Partículas Virais , Adulto Jovem
8.
Res Vet Sci ; 127: 47-56, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31677416

RESUMO

Recent studies have questioned the effect of maternal derived antibodies (MDAs) to protect piglets against infection with influenza A virus (IAV). The lack of protection against IAV infections provided by MDAs has encouraged alternative vaccination strategies targeting young piglets in an attempt to stimulate an early antibody response. There is a lack of studies documenting the efficacy of piglet vaccination. In the present study, we monitored a group of vaccinated and non-vaccinated piglets in a Danish sow herd that initiated piglet vaccination with » dose of an inactivated swine influenza vaccine at the time of castration (day 3-4). A total of 160 piglets from 11 sows were included and either vaccinated with 0.5 mL inactivated swine influenza vaccine or sham-vaccinated. From week 0 until week 6, all included piglets were clinically examined and nasal swapped once per week and weighed at weeks 0, 3 and 6. Blood samples were collected from sows at week 0 and from piglets at week 3. Vaccination of piglets had limited effect on clinical signs, body weight, antibody development and viral shedding, within the first 6 weeks of life. At least 50% of all pigs of each treatment group tested positive for IAV at week 2, and very early onset of IAV shedding was observed. In total, 18 pigs were IAV positive in nasal swabs for more than one consecutive sampling time indicating prolonged shedding and 14 pigs were IAV positive with negative samplings in between indicating re-infection with the same IAV strain.


Assuntos
Vírus da Influenza A/efeitos dos fármacos , Vacinas contra Influenza/farmacologia , Infecções por Orthomyxoviridae/veterinária , Doenças dos Suínos/prevenção & controle , Vacinação/veterinária , Animais , Anticorpos Antivirais/sangue , Formação de Anticorpos , Dinamarca , Vírus da Influenza A/fisiologia , Vacinas contra Influenza/administração & dosagem , Infecções por Orthomyxoviridae/prevenção & controle , Infecções por Orthomyxoviridae/virologia , Suínos , Doenças dos Suínos/virologia , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/farmacologia , Eliminação de Partículas Virais
9.
Medicine (Baltimore) ; 98(44): e17383, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689745

RESUMO

The risk of postnatal HIV transmission exists throughout the breastfeeding period. HIV shedding in breast milk beyond six months has not been studied extensively. The aim of this study was to determine prevalence and determinants of HIV shedding in breast milk during continued breastfeedingA cross-sectional study was nested in the PROMISE-PEP trial in Lusaka, Zambia to analyze breast milk samples collected from both breasts at week 38 post-partum (mid-way during continued breastfeeding). We measured concurrent HIV deoxyribonucleic acid (DNA) and HIV ribonucleic acid (RNA) as proxies for cell-associated HIV (CAV) and cell-free HIV (CFV) shedding in breast milk respectively. Participants' socio-demographic date, concurrent blood test results, sub clinical mastitis test results and contraceptive use data were available. Logistic regression models were used to identify determinants of HIV shedding in breast milk (detecting either CAV or CFV).The prevalence of HIV shedding in breast milk at 9 months post-partum was 79.4% (95%CI: 74.0 - 84.0). CAV only, CFV only and both CAV and CFV were detectable in 13.7%, 17.3% and 48.4% mothers, respectively. The odds of shedding HIV in breast milk decreased significantly with current use of combined oral contraceptives (AOR: 0.37; 95%CI: 0.17 - 0.83) and increased significantly with low CD4 count (AOR: 3.47; 95%CI: 1.23 - 9.80), unsuppressed plasma viral load (AOR: 6.27; 95%CI: 2.47 - 15.96) and severe sub-clinical mastitis (AOR: 12.56; 95%CI: 2.48 - 63.58).This study estimated that about 80% of HIV infected mothers not on ART shed HIV in breast milk during continued breastfeeding. Major factors driving this shedding were low CD4 count, unsuppressed plasma viral load and severe sub-clinical mastitis. The inverse relationship between breast milk HIV and use of combined oral contraceptives needs further clarification. Continued shedding of CAV may contribute to residual postnatal transmission of HIV in mothers on successful ART.


Assuntos
Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Leite Humano/virologia , Adulto , Antirretrovirais , Aleitamento Materno , Contagem de Linfócito CD4 , Ácidos Nucleicos Livres , Anticoncepcionais Orais Combinados/administração & dosagem , Estudos Transversais , DNA Viral , Feminino , Humanos , Transmissão Vertical de Doença Infecciosa , Modelos Logísticos , Mastite/epidemiologia , Mães , Prevalência , RNA Viral , Fatores Socioeconômicos , Carga Viral , Eliminação de Partículas Virais/fisiologia , Adulto Jovem , Zâmbia
10.
Vet Microbiol ; 239: 108451, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31767095

RESUMO

The substantial genetic diversity exhibited by influenza A viruses of swine (IAV-S) represents the main challenge for the development of a broadly protective vaccine against this important pathogen. The consensus vaccine immunogen has proven an effective vaccinology approach to overcome the extraordinary genetic diversity of RNA viruses. In this project, we sought to determine if a consensus IAV-S hemagglutinin (HA) immunogen would elicit broadly protective immunity in pigs. To address this question, a consensus HA gene (designated H3-CON.1) was generated from a set of 1,112 H3 sequences of IAV-S recorded in GenBank from 2011 to 2015. The consensus HA gene and a HA gene of a naturally occurring H3N2 IAV-S strain (designated H3-TX98) were expressed using the baculovirus expression system and emulsified in an oil-in-water adjuvant to be used for vaccination. Pigs vaccinated with H3-CON.1 immunogen elicited broader levels of cross-reactive neutralizing antibodies and interferon gamma secreting cells than those vaccinated with H3-TX98 immunogen. After challenge infection with a fully infectious H3N2 IAV-S isolate, the H3-CON.1-vaccinated pigs shed significantly lower levels of virus in their nasal secretions than the H3-TX98-vaccinated pigs. Collectively, our data provide a proof-of-evidence that the consensus immunogen approach may be effectively employed to develop a broadly protective vaccine against IAV-S.


Assuntos
Genes Virais/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vacinas contra Influenza/imunologia , Infecções por Orthomyxoviridae , Doenças dos Suínos , Vacinação/veterinária , Animais , Anticorpos Antivirais/sangue , Sequência Consenso/genética , Sequência Consenso/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/virologia , Eliminação de Partículas Virais/imunologia
11.
Vet Microbiol ; 239: 108495, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31767098

RESUMO

Bovine gammaherpesvirus type 4 (BoHV-4) is increasingly related with reproductive disease in cattle, but its epidemiology is not fully understood. We monitored the serological response and shedding of BoHV-4 in a positive dairy cattle farm with metritis. First, we performed an ELISA to detect BoHV-4 antibodies in all the animals (n = 104). Afterwards, ten seronegative heifers introduced in the production lot and sera samples were monthly taken for four months and then 6-10 months after introduction to detect BoHV-4 antibodies by ELISA. Moreover, a vaginal swab was taken after calving to detect BoHV-4 by PCR. Concurrently, a weekly collection of vaginal and nasal swabs and milk was performed during the first month post-partum in multiparous cows with metritis (n = 14), heifers with metritis (n = 4), heifers without metritis but positive to BoHV-4 (ELISA or PCR) (n = 2) and multiparous cows without metritis (n = 3). Seropositivity was higher in older animals and in the production lot. Three heifers which shed BoHV-4 after parturition resulted seronegative at first but eventually seroconverted. In the same vein, most heifers seroconverted after 6-10 months in the production lot (8/10). Multiparous cows shed virus by various routes: 13/14 (93 %) in vaginal secretions, 7/14 (50 %) in nasal exudates and 7/14 (50 %) in milk. However, in the other groups, shedding was only detected in vaginal swabs from the first week post-partum. Our study describes BoHV-4 shedding in field conditions. Seronegative animals may become horizontally infected when moved to a contaminated environment.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Herpesviridae/veterinária , Herpesvirus Bovino 4/fisiologia , Infecções Tumorais por Vírus/veterinária , Eliminação de Partículas Virais , Animais , Bovinos , Feminino , Infecções por Herpesviridae/sangue , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/virologia , Período Pós-Parto , Soroconversão , Infecções Tumorais por Vírus/sangue , Infecções Tumorais por Vírus/imunologia , Infecções Tumorais por Vírus/virologia , Vagina/virologia
12.
PLoS Pathog ; 15(10): e1008080, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31658304

RESUMO

Rubella viruses (RV) have been found in an association with granulomas in children with primary immune deficiencies (PID). Here, we report the recovery and characterization of infectious immunodeficiency-related vaccine-derived rubella viruses (iVDRV) from diagnostic skin biopsies of four patients. Sequence evolution within PID hosts was studied by comparison of the complete genomic sequences of the iVDRVs with the genome of the vaccine virus RA27/3. The degree of divergence of each iVDRV correlated with the duration of persistence indicating continuous intrahost evolution. The evolution rates for synonymous and nonsynonymous substitutions were estimated to be 5.7 x 10-3 subs/site/year and 8.9 x 10-4 subs/site/year, respectively. Mutational spectra and signatures indicated a major role for APOBEC cytidine deaminases and a secondary role for ADAR adenosine deaminases in generating diversity of iVDRVs. The distributions of mutations across the genes and 3D hotspots for amino acid substitutions in the E1 glycoprotein identified regions that may be under positive selective pressure. Quasispecies diversity was higher in granulomas than in recovered infectious iVDRVs. Growth properties of iVDRVs were assessed in WI-38 fibroblast cultures. None of the iVDRV isolates showed complete reversion to wild type phenotype but the replicative and persistence characteristics of iVDRVs were different from those of the RA27/3 vaccine strain, making predictions of iVDRV transmissibility and teratogenicity difficult. However, detection of iVDRV RNA in nasopharyngeal specimen and poor neutralization of some iVDRV strains by sera from vaccinated persons suggests possible public health risks associated with iVDRV carriers. Detection of IgM antibody to RV in sera of two out of three patients may be a marker of virus persistence, potentially useful for identifying patients with iVDRV before development of lesions. Studies of the evolutionary dynamics of iVDRV during persistence will contribute to development of infection control strategies and antiviral therapies.


Assuntos
Granuloma/virologia , Vacina contra Sarampo-Caxumba-Rubéola/efeitos adversos , Vírus da Rubéola/genética , Vírus da Rubéola/isolamento & purificação , Desaminases APOBEC/metabolismo , Adenosina Desaminase/metabolismo , Adolescente , Animais , Anticorpos Antivirais/sangue , Biópsia , Linhagem Celular , Criança , Genoma Viral/genética , Humanos , Imunoglobulina M/sangue , Vacina contra Sarampo-Caxumba-Rubéola/imunologia , Proteínas de Ligação a RNA/metabolismo , Pele/virologia , Células Vero , Proteínas do Envelope Viral/genética , Eliminação de Partículas Virais/genética
13.
Vet Microbiol ; 237: 108370, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31585643

RESUMO

Caprine alphaherpesvirus 1 (CpHV-1) is a pathogen associated with systemic infection and respiratory disease in kids and subclinical infection or reproductive failure and abortions in adult goats. The enzyme thymidine kinase (TK) is an important viral product involved in nucleotide synthesis. This property makes the tk gene a common target for herpesvirus attenuation. Here we deleted the tk gene of a CpHV-1 isolate and characterized the recombinant CpHV-1ΔTKin vitro and in vivo. In vitro characterization revealed that the recombinant CpHV-1ΔTK replicated to similar titers and produced plaques of similar size to the parental CpHV-1 strain in BT and CRIB cell lines. Upon intranasal inoculation of young goats, the parental virus replicated more efficiently and for a longer period than the recombinant virus. In addition, infection with the parental virus resulted in mild systemic and respiratory signs whereas the kids inoculated with the recombinant CpHV-1ΔTK virus remained healthy. Goats inoculated with the parental virus also developed higher neutralizing antibody titers when compared to CpHV-1ΔTK inoculated animals. Dexamethasone (Dx) administration on days 35-39 post-inoculation did not result in virus shedding in nasal secretions, indicating lack of reactivation from latency. However, viral DNA was detected in the trigeminal ganglia of animals euthanized at 14 days post-Dx, indicating that both viruses successfully established latent infection. Our results show that the recombinant CpHV-1ΔTK presents an attenuated phenotype when compared to the parental virus, and hence may represent a promising vaccine candidate to prevent CpHV-1 disease in goats.


Assuntos
Alphaherpesvirinae/genética , Deleção de Genes , Doenças das Cabras/virologia , Timidina Quinase/genética , Alphaherpesvirinae/patogenicidade , Animais , Bovinos , Linhagem Celular , DNA Viral/isolamento & purificação , Dexametasona/farmacologia , Regulação Enzimológica da Expressão Gênica , Regulação Viral da Expressão Gênica , Cabras , Muco/virologia , Proteínas Virais , Eliminação de Partículas Virais
14.
J Infect Dis ; 220(3): 411-419, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31535143

RESUMO

BACKGROUND: A conditionally replication-defective human cytomegalovirus (CMV) vaccine (V160) derived from AD169 and genetically engineered to express CMV pentameric complex (gH/gL/pUL128/pUL130/pUL131) was developed and evaluated for phase 1 vaccine safety and immunogenicity in CMV-seronegative and CMV-seropositive adults. METHODS: Subjects received 3 doses of V160 or placebo on day 1, month 1, and month 6. Four vaccine dose levels, formulated with or without aluminum phosphate adjuvant, were evaluated. Injection-site and systemic adverse events (AEs) and vaccine viral shedding were monitored. CMV-specific cellular and humoral responses were measured by interferon-gamma ELISPOT and virus neutralization assay up to 12 months after last dose. RESULTS: V160 was generally well-tolerated, with no serious AEs observed. Transient, mild-to-moderate injection-site and systemic AEs were reported more frequently in vaccinated subjects than placebo. Vaccine viral shedding was not detected in any subject, confirming the nonreplicating feature of V160. Robust neutralizing antibody titers were elicited and maintained through 12 months postvaccination. Cellular responses to structural and nonstructural viral proteins were observed, indicating de novo expression of viral genes postvaccination. CONCLUSIONS: V160 displayed an acceptable safety profile. Levels of neutralizing antibodies and T-cell responses in CMV-seronegative subjects were within ranges observed following natural CMV infection. CLINICAL TRIAL REGISTRATION: . NCT01986010.


Assuntos
Infecções por Citomegalovirus/imunologia , Vacinas contra Citomegalovirus/imunologia , Citomegalovirus/imunologia , Replicação Viral/imunologia , Adjuvantes Imunológicos/administração & dosagem , Adolescente , Adulto , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Método Duplo-Cego , ELISPOT/métodos , Feminino , Humanos , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Imunização/métodos , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia , Vacinação/métodos , Eliminação de Partículas Virais/imunologia , Adulto Jovem
15.
Emerg Microbes Infect ; 8(1): 1314-1323, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31495335

RESUMO

Within host-parasite communities, viral co-circulation and co-infections of hosts are the norm, yet studies of significant emerging zoonoses tend to focus on a single parasite species within the host. Using a multiplexed paramyxovirus bead-based PCR on urine samples from Australian flying foxes, we show that multi-viral shedding from flying fox populations is common. We detected up to nine bat paramyxoviruses shed synchronously. Multi-viral shedding infrequently coalesced into an extreme, brief and spatially restricted shedding pulse, coinciding with peak spillover of Hendra virus, an emerging fatal zoonotic pathogen of high interest. Such extreme pulses of multi-viral shedding could easily be missed during routine surveillance yet have potentially serious consequences for spillover of novel pathogens to humans and domestic animal hosts. We also detected co-occurrence patterns suggestive of the presence of interactions among viruses, such as facilitation and cross-immunity. We propose that multiple viruses may be interacting, influencing the shedding and spillover of zoonotic pathogens. Understanding these interactions in the context of broader scale drivers, such as habitat loss, may help predict shedding pulses of Hendra virus and other fatal zoonoses.


Assuntos
Coinfecção/veterinária , Transmissão de Doença Infecciosa , Infecções por Paramyxoviridae/veterinária , Paramyxovirinae/isolamento & purificação , Urina/virologia , Eliminação de Partículas Virais , Zoonoses/virologia , Animais , Quirópteros , Coinfecção/transmissão , Coinfecção/virologia , Infecções por Paramyxoviridae/transmissão , Infecções por Paramyxoviridae/virologia , Paramyxovirinae/classificação , Zoonoses/transmissão
16.
Vet Microbiol ; 236: 108374, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31500734

RESUMO

Foot-and-mouth disease (FMD) is a highly contagious disease and causes economic damage at a national level. In particular, the type O FMD virus (FMDV) is a serotype that causes FMD outbreaks most frequently in the world. In recent years, Southeast Asia (SEA), Middle East-South Asia (ME-SA), and Cathay topotype-mediated FMD are prevalent in Asia, among which the SEA and ME-SA topotypes cause a majority of the outbreaks. The SEA topotype virus is more likely to infect both cattle and pigs simultaneously, thereby resulting in more severe damages; thus, it is necessary to study the protection ability of the candidate vaccines of this topotype after immunization. In this study, an experimental vaccine for pigs was produced using a vaccine strain that contains the structural protein of the O Taiwan97 strain, which was derived from the Cathay topotype, and its effect was evaluated. In the immunization test in pigs and cattle, the antibody titers were found to be elevated two weeks after immunization and very high titers of neutralizing antibodies were formed after four weeks. After the second inoculation, very high titers of neutralizing antibodies were produced in both species in the fourth week after immunization, and the antibodies maintained for up to six months and three months in cattle and pigs, respectively. No significant immunological difference in antibody production was observed in cattle and pigs. This study confirmed that complete protection from the challenge of the SEA topotype virus (O/Jincheon/SKR/2014), although the antibody titers against O/Jincheon/SKR/2014 strain were not that high, was achieved through immunization with the newly developed Cathay topotype vaccine in pigs.


Assuntos
Vírus da Febre Aftosa/classificação , Febre Aftosa/prevenção & controle , Doenças dos Suínos/prevenção & controle , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/sangue , Febre Aftosa/epidemiologia , Febre Aftosa/virologia , Camundongos , Camundongos Endogâmicos ICR , República da Coreia/epidemiologia , Suínos , Doenças dos Suínos/virologia , Eliminação de Partículas Virais
17.
Nat Commun ; 10(1): 3526, 2019 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-31387995

RESUMO

Segmentation of viral genomes into multiple RNAs creates the potential for replication of incomplete viral genomes (IVGs). Here we use a single-cell approach to quantify influenza A virus IVGs and examine their fitness implications. We find that each segment of influenza A/Panama/2007/99 (H3N2) virus has a 58% probability of being replicated in a cell infected with a single virion. Theoretical methods predict that IVGs carry high costs in a well-mixed system, as 3.6 virions are required for replication of a full genome. Spatial structure is predicted to mitigate these costs, however, and experimental manipulations of spatial structure indicate that local spread facilitates complementation. A virus entirely dependent on co-infection was used to assess relevance of IVGs in vivo. This virus grows robustly in guinea pigs, but is less infectious and does not transmit. Thus, co-infection allows IVGs to contribute to within-host spread, but complete genomes may be critical for transmission.


Assuntos
Vírus Defeituosos/patogenicidade , Genoma Viral , Vírus da Influenza A Subtipo H3N2/patogenicidade , Influenza Humana/transmissão , Replicação Viral/genética , Animais , Vírus Defeituosos/genética , Modelos Animais de Doenças , Cães , Evolução Molecular , Feminino , Cobaias , Células HEK293 , Humanos , Vírus da Influenza A Subtipo H3N2/genética , Influenza Humana/virologia , Funções Verossimilhança , Células Madin Darby de Rim Canino , Modelos Biológicos , RNA Viral/genética , Análise de Célula Única , Carga Viral , Vírion/genética , Eliminação de Partículas Virais/genética
18.
Vet Microbiol ; 235: 220-228, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31383305

RESUMO

The highly virulent porcine epidemic diarrhea virus (PEDV) variants cause the death of mainly neonatal piglets, but how the viruses spread within the gastro-intestinal tract in a temporal and spatial manner has remained poorly characterized but is critical to understand the viral pathogenesis. In this study, we used the Chinese PEDV epidemic strain BJ2011C as a model organism and took advantage of the newly developed RNAscope in situ hybridization technology to investigate the tempo-spatial infection dynamics in neonatal piglets. We found that the PEDV strain BJ2011C could quickly colonize the small intestine, which occurred in just 6 h post infection, with virus shedding starting at 6 hpi and peaking at 24 hpi. Jejunum was the first target tissue for infection and then ileum, followed by infrequent infection of duodenum. In these tissues, the virus nucleic acids were mainly present in the villous epithelial cells but not in crypt cells. Interestingly, the viral RNAs were not detectable by RNAscope in large intestines although tissue damages could be discerned by H & E staining. Overall, our results provide useful information about spread dynamics and tissue preference of PEDV epidemic strain BJ2011C.


Assuntos
Infecções por Coronavirus/patologia , Intestino Delgado/virologia , Vírus da Diarreia Epidêmica Suína/patogenicidade , RNA Viral/isolamento & purificação , Doenças dos Suínos/patologia , Animais , Animais Recém-Nascidos , Diarreia/veterinária , Diarreia/virologia , Células Epiteliais/virologia , Hibridização in Situ Fluorescente , Jejuno/citologia , Jejuno/virologia , Suínos , Doenças dos Suínos/virologia , Eliminação de Partículas Virais
19.
Vet Microbiol ; 235: 319-326, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31383319

RESUMO

Porcine kobuviruses are widely distributed in swine, but the clinical significance of these viruses remains unclear, since they have been associated with both diarrheic and healthy pigs. In addition, there is a paucity of data on Kobuvirus prevalence in Canadian pig herds. In this study, a total of 181 diarrheic and healthy piglets were monitored and sampled on four occasions, intended to represent the different stages of production. The piglets were sampled at the nursing farms (birth to weaning stage), at the nursery farms (post-weaning stage), and at finishing farms (at the beginning and the end of the fattening stage). Fecal and environmental samples were collected during each life stage. Following viral extraction, Kobuvirus detection by RT-PCR was conducted, and positive samples were sequenced. During the late-nursing stage (6-21 days old), piglets with diarrhea shed more Kobuvirus than healthy individuals. Piglets shed more Kobuvirus during the post-weaning stage (nursery farms) than during any of the other life stages. This was evidenced in individual samples as well as in environmental samples. Over 97% of the sampled piglets shed Kobuvirus at least once in their lifetime. All piglets shedding a Kobuvirus strain or mix of strains at the nursing stage did not appear to shed another porcine kobuvirus strain at a later life stage. Overall, our findings throw light on Kobuvirus shedding dynamics and their potential role in neonatal diarrhea at the nursing stage, which appears to be the point of entry for kobuviruses into swine production systems.


Assuntos
Diarreia/veterinária , Kobuvirus/fisiologia , Infecções por Picornaviridae/veterinária , Doenças dos Suínos/virologia , Eliminação de Partículas Virais , Fatores Etários , Animais , Diarreia/virologia , Fazendas , Fezes/virologia , Kobuvirus/isolamento & purificação , Filogenia , Infecções por Picornaviridae/virologia , RNA Viral , Análise de Sequência de DNA , Suínos , Desmame
20.
Gene Ther ; 26(9): 399-406, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31467408

RESUMO

Differences between mouse and human hearts pose a significant limitation to the value of small animal models when predicting vector behavior following recombinant adeno-associated viral (rAAV) vector-mediated cardiac gene therapy. Hence, sheep have been adopted as a preclinical animal, as they better model the anatomy and cardiac physiological processes of humans. There is, however, no comprehensive data on the shedding profile of rAAV in sheep following intracoronary delivery, so as to understand biosafety risks in future preclinical and clinical applications. In this study, sheep received intracoronary delivery of rAAV serotypes 2/6 (2 × 1012 vg), 2/8, and 2/9 (1 × 1013 vg) at doses previously administered in preclinical and clinical trials. This was followed by assessment over 96 h to examine vector shedding in urine, feces, nasal mucus, and saliva samples. Vector genomes were detected via real-time quantitative PCR in urine and feces up to 48 and 72 h post vector delivery, respectively. Of these results, functional vector particles were only detected via a highly sensitive infectious replication assay in feces samples up to 48 h following vector delivery. We conclude that rAAV-mediated gene transfer into sheep hearts results in low-grade shedding of non-functional vector particles for all excreta samples, except in the case of feces, where functional vector particles are present up to 48 h following vector delivery. These results may be used to inform containment and decontamination guidelines for large animal dealings, and to understand the biosafety risks associated with future preclinical and clinical uses of rAAV.


Assuntos
Dependovirus/genética , Vetores Genéticos , Eliminação de Partículas Virais , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Cateterismo , Vasos Coronários , Dependovirus/imunologia , Dependovirus/fisiologia , Vetores Genéticos/administração & dosagem , Vetores Genéticos/imunologia , Células HeLa , Humanos , Injeções Intra-Arteriais , Masculino , Infecções por Parvoviridae/imunologia , Infecções por Parvoviridae/urina , Infecções por Parvoviridae/virologia , Reação em Cadeia da Polimerase em Tempo Real , Ovinos , Replicação Viral
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