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1.
An Acad Bras Cienc ; 91(3): e20180860, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31553367

RESUMO

The first cases of Zika virus infection in Colombia were reported and confirmed in October 2015. The objective of the study was estimate the seroprevalence of ZIKV infection during the pre-epidemic phase in Barranquilla, Colombia, and demonstrate the presence of virus before the Colombian Ministry of Health confirmed the first case. We conducted a descriptive study of the seroprevalence of Zika virus in 390 samples obtained from a blood bank located in Barranquilla, Colombia - a city endemic for dengue, and with a recent history of a Chikungunya disease epidemic. The serum pools were tested using Euroimmun ZIKV ELISA kit. Seroprevalence of Zika virus IgG were: May 2015: 0%, June and July 2015: 2.62% (95% CI = 0.28-12.13) and August 2015: 5.35% (95% CI = 1.74-16.74). This brings to our attention the need for extending the surveillance period of this virus in order to adequately assess its teratogenic effects.


Assuntos
Anticorpos Antivirais/sangue , Doadores de Sangue/estatística & dados numéricos , Imunoglobulina G/sangue , Infecção por Zika virus/sangue , Zika virus/imunologia , Colômbia/epidemiologia , Ensaio de Imunoadsorção Enzimática , Humanos , Estudos Soroepidemiológicos
2.
Acta Virol ; 63(3): 301-308, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31507196

RESUMO

Transmissible gastroenteritis virus (TGEV) causes great economic loss to swine industry worldwide. Vaccination is an important method to control the TGEV infection. In this study, a TGEV oral vaccine was generated by transferring a eukaryotic expression recombinant plasmid carrying the SAD (A and D antigenic sites of the S protein) epitope of TGEV into a swine-origin Lactobacillus acidophilus (L. acidophilus). In orally immunized BALB/c mice, the TGEV L. acidophilus oral vaccine induced significantly higher level of SIgA antibodies specific to TGEV compared with the mice immunized with a commercial inactivated TGEV vaccine and similar levels of IgG specific to TGEV as the inactivated vaccine. Furthermore, the TGEV L. acidophilus oral vaccine induced higher levels of IFN-γ, which suggested that the vaccine was able to induce immune response. In brief, this novel TGEV L. acidophilus oral vaccine could induce high levels of both mucosal and humoral immune responses, which has a potential to be used in the pig industries in the future. Keywords: transmissible gastroenteritis virus (TGEV); live L. acidophilus oral vaccine; SIgA antibody; IgG antibody; IFN-γ; IL-4.


Assuntos
Anticorpos Antivirais , Epitopos , Gastroenterite Suína Transmissível , Lactobacillus acidophilus , Vírus da Gastroenterite Transmissível , Vacinas Virais , Administração Oral , Animais , Anticorpos Antivirais/sangue , Epitopos/genética , Epitopos/imunologia , Gastroenterite Suína Transmissível/imunologia , Gastroenterite Suína Transmissível/patologia , Imunogenicidade da Vacina/imunologia , Lactobacillus acidophilus/genética , Lactobacillus acidophilus/virologia , Camundongos , Camundongos Endogâmicos BALB C , Plasmídeos/genética , Suínos , Proteínas Virais/genética , Proteínas Virais/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/imunologia
3.
BMC Vet Res ; 15(1): 274, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31370852

RESUMO

BACKGROUND: In Poland, the leader in goose production in Europe, goose parovirus infection, or Derzsy's disease (DD), must be reported to the veterinary administration due to the serious economic and epizootic threat to waterfowl production. Prophylactic treatment for DD includes attenuated live or inactivated vaccines. Moreover, the control of DD includes the monitoring of maternal derived antibody (MDA) levels in the offspring and antibody titers in the parent flock after vaccination. The aim of this study was to develop an ELISA for the detection of goose parvovirus (GPV) antibodies. RESULTS: Two recombinant protein fragments derived from VP3 (viral protein 3) GPV, namely VP3ep6 and VP3ep4-6 with a mass of 20.9 and 32.3 kDa, respectively, were produced using an Escherichia coli expression system. These proteins were purified by one-step nickel-affinity chromatography, which yielded protein preparations with a purity above 95%. These recombinant proteins were useful in the detection of serum anti-GPV antibodies, and this was confirmed by Western blotting. However, recombinant VP3ep4-6 protein showed a greater ability to correctly identify sera from infected geese. In the next stage of the project, a pool of 166 goose sera samples, previously examined by a virus neutralization test (VN), was tested. For further studies, one recombinant protein (VP3ep4-6) was selected for optimization of the test conditions. After optimization, the newly developed ELISA was compared to other serological tests, and demonstrated high sensitivity and specificity. CONCLUSION: In conclusion, the VP3ep4-6 ELISA method described here can be used for the detection of antibodies to GPV in serum.


Assuntos
Anticorpos Antivirais/sangue , Proteínas do Capsídeo/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Infecções por Parvoviridae/veterinária , Parvovirinae/imunologia , Doenças das Aves Domésticas/diagnóstico , Animais , Ensaio de Imunoadsorção Enzimática/normas , Infecções por Parvoviridae/sangue , Infecções por Parvoviridae/diagnóstico , Doenças das Aves Domésticas/sangue , Doenças das Aves Domésticas/virologia , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade
4.
Acta Vet Scand ; 61(1): 41, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31455410

RESUMO

BACKGROUND: Villegas-Glisson/University of Georgia (VG/GA) strain of Newcastle disease virus (NDV) is recommended for the initial vaccination of commercially reared turkey poults. However, the vaccine-induced antibody responses have not been studied in this species. The level of systemic humoral immune responses against the NDV was investigated in commercial turkey poults vaccinated with the VG/GA vaccine. One hundred eighty-two hybrid strain of turkey poults (Meleagris gallopavo) were divided randomly into vaccinated and unvaccinated groups. The vaccinated group was given the VG/GA vaccine at 10 and 20 days of age. To investigate the vaccine immunity, the level of specific IgY and IgA in serum samples were determined using ELISA and haemagglutination inhibition assays (HI). The biological half-life of maternal antibodies was also determined before the immunization. RESULTS: VG/GA-specific antibodies were detected in the vaccinated turkey poults and were significantly higher in the vaccinated group compared to the unvaccinated group. IgY and IgA antibodies showed a significant increase in titers 14 days after the second vaccination and reached a peak on day 35 of age. The correlation coefficient and intra-rater reliability showed a significant correlation between the HI titers and IgY/IgA ELISA values. Maternal IgY and IgA levels were found to decline in the serum with half-lifes of 7.68 ± 2.35 and 2.18 ± 0.82 days, respectively. CONCLUSIONS: Enterotropic lentogenic VG/GA vaccine induced a marked humoral immune response against the NDV in turkey poults. The positive correlation between IgY and IgA highlights the role of these two antibody classes in controlling the Newcastle disease in turkey poults.


Assuntos
Imunidade Humoral/imunologia , Doença de Newcastle/imunologia , Vírus da Doença de Newcastle/imunologia , Doenças das Aves Domésticas/imunologia , Perus , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/sangue , Doença de Newcastle/prevenção & controle , Doenças das Aves Domésticas/prevenção & controle
5.
Vet Immunol Immunopathol ; 213: 109888, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31307673

RESUMO

Felis catus papillomavirus type 2 (FcaPV-2) commonly infects the skin of domestic cats and has been associated with the development of skin cancer. In the present study, a FcaPV-2 virus-like particle (VLP) vaccine was produced and assessed for vaccine safety, immunogenicity, and impact on FcaPV-2 viral load. This is the first report of the use of a papillomavirus VLP vaccine in domestic cats. The FcaPV-2 VLP vaccine was given to ten adult cats that were naturally infected with FcaPV-2, and a further ten naturally infected cats were sham vaccinated as a control group. The rationale for vaccinating cats already infected with the virus was to induce neutralizing antibody titers that could prevent reinfection of new areas of skin and reduce the overall viral load, as has been demonstrated in other species. Reducing the overall FcaPV-2 viral load could reduce the risk for subsequent PV-associated cancer. The vaccine in this study was well-tolerated, as none of the cats developed any signs of local reaction or systemic illness. In the treatment group, the geometric mean anti-papillomavirus endpoint antibody titers increased significantly following vaccination from 606 (95% CI 192-1913) to 4223 (2023-8814), a 7.0-fold increase, although the individual antibody response varied depending on the level of pre-existing antibodies. Despite the immunogenicity of the vaccine, there was no significant change in FcaPV-2 viral load in the treatment group compared to the control group, over the 24 week follow-up period. A possible reason is that FcaPV-2 was already widespread in the basal skin layer of these adult cats and so preventing further cells from becoming infected had no impact on the overall viral load. Therefore, these results do not support the use of a FcaPV-2 VLP vaccine to reduce the risk for PV-associated cancer in cats in which FcaPV-2 infection is already well established. However, these results justify future studies in which the vaccine is administered to younger cats prior to FcaPV-2 infection becoming fully established.


Assuntos
Doenças do Gato/prevenção & controle , Imunogenicidade da Vacina , Infecções por Papillomavirus/veterinária , Neoplasias Cutâneas/veterinária , Carga Viral , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/sangue , Doenças do Gato/virologia , Gatos , DNA Viral/sangue , Feminino , Masculino , Papillomaviridae/genética , Papillomaviridae/imunologia , Infecções por Papillomavirus/prevenção & controle , Reação em Cadeia da Polimerase , Testes Sorológicos , Pele/patologia , Pele/virologia , Neoplasias Cutâneas/prevenção & controle , Neoplasias Cutâneas/virologia , Vacinas de Partículas Semelhantes a Vírus/imunologia
6.
J Zoo Wildl Med ; 50(2): 337-341, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31260198

RESUMO

Canine distemper virus (CDV) vaccination using commercial vaccines has been recommended as a useful preventive tool in zoological collections worldwide for the past 30 yr. Zoological facilities have not conducted studies to assess the effectiveness and safety of the multivalent Recombitek C6 and C8 in nondomestic carnivores. They are the only CDV recombinant vaccines available in Latin America. Seventeen clinically healthy red foxes born in Buin Zoo were divided into three groups and administered 1 ml of Recombitek C6 vaccine. Group A consisted of three animals of 9 mo of age without previous vaccination (WPV) that received a single dose. Group B consisted of four animals of 10 mo of age WPV; they received a series of three doses with a 21-day interval between doses. Group C consisted of eight animals > 1 yr of age that had received a previous vaccination > 1 yr ago; they received a single-dose booster vaccination. Titers for antibodies against CDV were measured by a serum neutralization test. All animals remained clinically healthy throughout the study period and without clinical signs of disease. Only two foxes (group C) did not show any increase in the antibody titer to the vaccine. All animals of groups A and B seroconverted at 21 days after the first vaccination. Only two animals (both from group B) showed an adequate antibody protective response (titers >100) after 180 days. Absence of adverse reactions in red foxes included in this study supports the safety and apparently nondeleterious effect of CDV recombinant vaccine reported in other nondomestic carnivores. Low antibody response and lack of persistence in the serological response 6 mo after vaccination with a single dose suggested limited protective benefits in this species. Additional research is needed to confirm the antibody titer response to multiple vaccinations in this species.


Assuntos
Vírus da Cinomose Canina , Raposas/imunologia , Vacinas Virais/imunologia , Animais , Animais de Zoológico , Anticorpos Antivirais/sangue , Cinomose/prevenção & controle , Raposas/sangue , Esquemas de Imunização , Imunização Secundária , Vacinação/veterinária , Vacinas Sintéticas
7.
J Zoo Wildl Med ; 50(2): 478-481, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31260219

RESUMO

Red pandas (Ailurus fulgens) are susceptible to canine distemper, with a number of reported vaccine-induced canine distemper cases. Canarypox-vectored recombinant canine distemper vaccines (PureVax Ferret Distemper [PFD] and Recombitek CDV [rCDV]) provide protection without inoculating a live distemper virus, but there are currently no published data regarding these vaccines' safety and efficacy in red pandas. One hundred twenty-two serum samples were collected from 50 captive red pandas and analyzed for antibodies to canine distemper. All naïve red pandas (n = 20) had negative titers. Naïve pandas receiving two PFD vaccinations had either negative or intermediate titers (n = 4). In contrast, naïve pandas receiving a series of two or three rCDV vaccinations (n = 14) had greater antibody responses. Red pandas vaccinated with PFD >12 mo since their last vaccination and a rCDV booster vaccination showed the highest titers observed. We recommend red pandas be administered a series of at least three recombinant vaccine (PDF or rDCV) vaccinations, followed by annual booster vaccinations.


Assuntos
Ailuridae/sangue , Anticorpos Antivirais/sangue , Vírus da Cinomose Canina/imunologia , Cinomose/prevenção & controle , Vacinas Virais/imunologia , Animais , Cinomose/virologia , Vetores Genéticos , Imunização Secundária , Vacinação , Vacinas Sintéticas/imunologia
8.
BMC Infect Dis ; 19(1): 590, 2019 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-31277583

RESUMO

BACKGROUND: Transfusion-Transmitted Zika virus (TT-ZIKV) has become an emerging threat to world blood banks due to the fast spread of ZIKV epidemics and high rate of asymptomatic infections. For the risk assessment of ZIKV infection in blood products, relevant studies in blood donations or blood donors tested for ZIKV were collected and analyzed systematically. The overall prevalence of ZIKV infection were estimated through meta-analysis and potential risk factors were detected. The results will provide important clues for the protocol design of blood screening tests. METHODS: Relevant articles about the rate of ZIKV detected in blood samples were identified from PubMed, Scopus and Web Of Science using key terms search strategy until October 7, 2017. Eligible articles were screened following inclusion and exclusion criteria. Meta-analysis and subgroup analyses were performed by software R3.4.1. Overall postdonation and posttransfusion follow-ups were analyzed. RESULTS: Ten literatures (528,947 blood samples) were included for meta-analysis. The overall pooled prevalence of ZIKV (RNA and antibody) in blood donations was 1.02% (95%CI 0.36-1.99). The pooled prevalence of ZIKV RNA in blood donations was 0.85% (95%CI 0.21-1.88) less than the pooled prevalence of anti-ZIKV antibodies 1.61% (95%CI 0.03-5.21), however the difference was not statistically significant (p = 0.52). The prevalence varied significantly in different geographical regions (p < 0.001). Blood donations were more than two times likely to be infected by ZIKV in Zika epidemic period (1.37, 95%CI 0.91-1.91) than in non-epidemic period (0.61, 95%CI 0-2.55). The prevalence of anti-ZIKV antibodies (1.61, 95%CI 0.03-5.21) was almost twice as much as ZIKV nucleic acid detected in blood donations (0.85, 95%CI 0.21-1.88). However, statistically significant differences were not observed. A total of 122 ZIKV positive blood donors were followed, of which 48 (39%) reported symptoms postdonation, but none of the 13 followed recipients reported any clinical symptoms related to Zika infection posttransfusion. CONCLUSION: The pooled prevalence of Zika infection in blood donations was 1.02%. The prevalence varied greatly and reached to high-risk level in most of the situations. The results suggest that nucleic acid tests (NAT) for blood screening and pathogen reduction/inactivation technology (PRT) should be implemented in Zika-endemic areas and appropriate strategies should be designed according to different conditions. More studies are needed in the future to provide more evidence.


Assuntos
Doadores de Sangue/estatística & dados numéricos , Infecção por Zika virus , Zika virus , Anticorpos Antivirais/sangue , Humanos , Prevalência , RNA Viral/sangue , Zika virus/genética , Zika virus/imunologia , Infecção por Zika virus/sangue , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/epidemiologia
9.
BMC Infect Dis ; 19(1): 591, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31286879

RESUMO

BACKGROUND: We report a rare case of Toscana virus infection imported into Switzerland in a 23-year old man who travelled to Imperia (Italy) 10 days before onset of symptoms. Symptoms included both meningitis and as well epididymitis. This is only the fourth case of Toscana virus reported in Switzerland. CASE PRESENTATION: The patient presented with lymphocytic meningitis and scrotal pain due to epididymitis. Meningitis was initially treated with ceftriaxone. Herpes simplex, tick-borne encephalitis, enterovirus, measles, mumps, rubella and Treponema pallidum were excluded with specific polymerase chain reaction (PCR) or serology. In support of routine diagnostic PCR and serology assays, unbiased viral metagenomic sequencing was performed of cerebrospinal fluid and serum. Toscana virus infection was identified in cerebrospinal fluid and the full coding sequence could be obtained. Specific PCR in cerebrospinal fluid and blood and serology with Immunoglobulin (Ig) M and IgG against Toscana virus confirmed our diagnosis. Neurological symptoms recovered spontaneously after 5 days. CONCLUSIONS: This case of Toscana virus infection highlights the benefits of unbiased metagenomic sequencing to support routine diagnostics in rare or unexpected viral infections. With increasing travel histories of patients, physicians should be aware of imported Toscana virus as the agent for viral meningitis and meningoencephalitis.


Assuntos
Infecções por Bunyaviridae , Epididimite , Meningite Viral , Metagenômica/métodos , Vírus da Febre do Flebótomo Napolitano , Adulto , Anticorpos Antivirais/sangue , Infecções por Bunyaviridae/diagnóstico , Infecções por Bunyaviridae/imunologia , Infecções por Bunyaviridae/virologia , Epididimite/diagnóstico , Epididimite/imunologia , Epididimite/virologia , Humanos , Itália , Masculino , Meningite Viral/diagnóstico , Meningite Viral/imunologia , Meningite Viral/virologia , Técnicas de Diagnóstico Molecular , RNA Viral/genética , Vírus da Febre do Flebótomo Napolitano/genética , Vírus da Febre do Flebótomo Napolitano/imunologia , Análise de Sequência de RNA , Suíça , Adulto Jovem
10.
BMC Vet Res ; 15(1): 236, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31286926

RESUMO

BACKGROUND: Lumpy skin disease (LSD) is a transboundary cattle disease caused by a Capripoxvirus of the family Poxviridae. In Uganda, documented information on the epidemiology of the disease is rare and there is no nationwide control plan, yet LSD is endemic. This study set out to investigate the seroprevalence of lumpy skin disease and determine the risk factors for LSD seropositivity, by carrying out a cross-sectional study in 21 districts of Uganda. RESULTS: A total of 2,263 sera samples were collected from 65 cattle herds and an indirect ELISA was used to screen for lumpy skin disease virus (LSDV) antibodies. We used univariable and multivariable mixed effect logistic regression models to identify risk factors for LSD seropositivity. The overall animal and herd-level seroprevalences were 8.7% (95% CI: 7.0-9.3) and 72.3% (95% CI: 70.0-80.3), respectively. Animal-level seroprevalence in Central region (OR = 2.13, p = 0.05, 95% CI: 1.10-4.64) was significantly different from the Northern region (Reference) and Western region (OR = 0.84, p = 0.66, 95% CI: 0.39-1.81). Management type, sex, age, mean annual precipitation > 1000 mm, and drinking from communal water sources were statistically significant risk factors for occurrence of anti-LSDV antibodies in cattle. Breed, region, herd size, contact with buffalo and other wildlife and introduction of new cattle did not have a statistically significant association with being positive for LSDV. CONCLUSION: We report a high herd-level LSDV seroprevalence in Uganda with a moderate animal-level seroprevalence. Cattle with the highest risk of LSD infection in Uganda are those in fenced farms, females > 25 months old, in an area with a mean annual rainfall > 1000 mm, and drinking from a communal water source.


Assuntos
Anticorpos Antivirais/sangue , Doença Nodular Cutânea/epidemiologia , Animais , Bovinos , Estudos Transversais , Feminino , Vírus da Doença Nodular Cutânea , Masculino , Fatores de Risco , Estudos Soroepidemiológicos , Uganda/epidemiologia
11.
Vet Microbiol ; 235: 1-9, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31282365

RESUMO

Oral immunization is a commonly employed route for inducing local immunity. However, the application of oral immunization is limited by the short-term persistence of immunity, particularly for inactivated viruses. The ultimate goal for mucosal vaccination is to stimulate protective immunological memory. In the intestine, long-term persistence of immunity is related to CD4+CD8+ memory T-cells. In this study, piglets were orally immunized with Bacillus subtilis spores (B.s) plus whole inactivated porcine epidemic diarrhea virus (PEDV WIV), followed by booster oral immunization. Initially, the results showed that B.s plus PEDV WIV enhanced the anti-PEDV capability on mucosal surfaces, as evidenced by plaque reduction neutralization tests in serum and intestinal fluid. Elevated antigen-specific IgG titers in the serum and IgA titers in saliva, feces and nasal washing liquid were also observed. Meanwhile, B.s plus PEDV WIV increased the area of Peyer's patches and the number of intraepithelial lymphocytes in the ileum of piglets. Similarly, the percentage of CD4+CD8+ memory T-cells were upregulated and proliferation ability of antigen-specific memory T-cell was strengthened in intestinal mucosal-associated lymphocytes, which was accompanied with increased expression of CCR9 after oral immunization with B.s plus PEDV WIV. In addition, the activation of memory T-cells is correlated with the increased mRNA expression of Toll-like receptor 2 and 4, as well as interleukin-6 and induced by B.s. Collectively, the study provided further insight into the potential immunopotentiator ability of B.s to assist PEDV WIV in the potentiation of immunity by upregulating memory CD4+CD8+ T cells via oral immunization.


Assuntos
Bacillus subtilis/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Memória Imunológica , Mucosa Intestinal/imunologia , Vírus da Diarreia Epidêmica Suína/imunologia , Administração Oral , Animais , Anticorpos Antivirais/sangue , Imunização/métodos , Imunização Secundária , Imunoglobulina G/sangue , Esporos/imunologia , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/prevenção & controle , Regulação para Cima , Vacinas de Produtos Inativados/imunologia
12.
Vet Microbiol ; 235: 10-20, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31282366

RESUMO

African Swine Fever Virus (ASFV) causes a hemorrhagic disease in swine and wild boars with a fatality rate close to 100%. Less virulent strains cause subchronic or chronic forms of the disease. The virus is endemic in sub-Saharan Africa and an outbreak in Georgia in 2007 spread to Armenia, Russia, Ukraine, Belarus, Poland, Lithuania, and Latvia. In August 2018, there was an outbreak in China and in April 2019, ASFV was reported in Vietnam and Cambodia. Since no vaccine or treatment exists, a vaccine is needed to safeguard the swine industry. Previously, we evaluated immunogenicity of two adenovirus-vectored cocktails containing ASFV antigens and demonstrated induction of unprecedented robust antibody and T cell responses, including cytotoxic T lymphocytes. In the present study, we evaluated protective efficacy of both cocktails by intranasal challenge of pigs with ASFV-Georgia 2007/1. A nine antigen cocktail-(I) formulated in BioMize adjuvant induced strong IgG responses, but when challenged, the vaccinees had more severe reaction relative to the controls. A seven antigen cocktail-(II) was evaluated using two adjuvants: BioMize and ZTS-01. The BioMize formulation induced stronger antibody responses, but 8/10 vaccinees and 4/5 controls succumbed to the disease or reached experimental endpoint at 17 days post-challenge. In contrast, the ZTS-01 formulation induced weaker antibody responses, but 4/9 pigs succumbed to the disease while the 5 survivors exhibited low clinical scores and no viremia at 17 days post-challenge, whereas 4/5 controls succumbed to the disease or reached experimental endpoint. Overall, none of the immunogens conferred statistically significant protection.


Assuntos
Febre Suína Africana/prevenção & controle , Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , Vacinas Virais/imunologia , Adenoviridae , Administração Intranasal , Febre Suína Africana/imunologia , Vírus da Febre Suína Africana , Animais , Antígenos Virais/genética , Imunoglobulina G/sangue , Suínos , Linfócitos T Citotóxicos/imunologia , Vacinas de Subunidades/imunologia , Proteínas Virais/genética , Proteínas Virais/imunologia , Vacinas Virais/genética , Viremia , Virulência
13.
Vet Microbiol ; 235: 86-92, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31282383

RESUMO

Although PCV2 infections generally cause mild disease in pigs, concurrent co-infections with other pathogens can damage the immune system and cause more severe diseases, collectively termed porcine circovirus associated diseases (PCVAD). Involvement of porcine parvovirus (PPV, a common cause of reproductive failure in naïve dams) in PCVAD caused by PCV2, has been reported. As this co-infection can be difficult to eliminate, there is a critical need to develop an effective vaccine to protect against PPV or synergistic effects of PCV2 and PPV under field conditions. In this study, we designed chimeric PCV2 virus-like particles (cVLPs) displaying a B-cell epitope derived from PPV1 structural protein around the surface of the 2-fold axes of PCV2 VLPs, based on 3D-structure analysis of the PCV2 capsid. The cVLPs were successfully prepared, verified by transmission electron microscopy and chromatography, with robust antibody titers against PCV2 and PPV1 produced in mice and guinea pigs. In addition, in guinea pigs challenged with 106 TCID50 PCV2, cVLPs conferred more effective immune protection (based on viral load) than a commercial PCV2 vaccine. Finally, antibody responses and immune protection against PPV were also evaluated. In guinea pigs vaccinated with cVLPs, although PPV antibodies detected by a hemagglutination inhibition (HI) assay appeared later after vaccination in the PCV2 cVLPs group than in the commercial PPV vaccine group, there were fewer PPV genomic DNA copies in the PCV2 cVLPs group than in a PBS group. In conclusion, guinea pigs vaccinated with cVLPs developed effective protective immunity against PCV2 challenge, with some protective immunity against PPV. This study provided valuable research data to pursue molecular design of chimeric epitopes PCV2 VLPs.


Assuntos
Infecções por Circoviridae/veterinária , Coinfecção/veterinária , Epitopos de Linfócito B/imunologia , Imunidade Humoral , Infecções por Parvoviridae/veterinária , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Linfócitos B/imunologia , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/prevenção & controle , Circovirus/imunologia , Coinfecção/virologia , Feminino , Cobaias , Camundongos , Infecções por Parvoviridae/imunologia , Infecções por Parvoviridae/prevenção & controle , Parvovirus Suíno/imunologia , Suínos , Doenças dos Suínos/prevenção & controle , Doenças dos Suínos/virologia , Vacinas Atenuadas/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia
14.
Scand J Immunol ; 90(4): e12801, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31269273

RESUMO

Influenza virus is a major respiratory pathogen, and vaccination is the main method of prophylaxis. In 2012, the trivalent live attenuated influenza vaccine (LAIV) was licensed in Europe for use in children. Vaccine-induced antibodies directed against the main viral surface glycoproteins, haemagglutinin (HA) and neuraminidase (NA) play important roles in limiting virus infection. The objective of this study was to dissect the influenza-specific antibody responses in children and adults, and T cell responses in children induced after LAIV immunization to the A/H1N1 virus. Blood samples were collected pre- and at 28 and 56 days post-vaccination from 20 children and 20 adults. No increase in micro-neutralization (MN) antibodies against A/H1N1 was observed after vaccination. A/H1N1 stalk-specific neutralizing and NA-inhibiting (NI) antibodies were boosted in children after LAIV. Interferon γ-producing T cells increased significantly in children, and antibody-dependent cellular-mediated cytotoxic (ADCC) cell activity increased slightly in children after vaccination, although this change was not significant. The results indicate that the NI assay is more sensitive to qualitative changes in serum antibodies after LAIV. There was a considerable difference in the immune response in children and adults after vaccination, which may be related to priming and previous influenza history. Our findings warrant further studies for evaluating LAIV vaccination immunogenicity.


Assuntos
Vírus da Influenza A Subtipo H1N1/fisiologia , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Vacinas Atenuadas/imunologia , Adulto , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Criança , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Imunidade Humoral , Masculino , Vacinação
15.
BMC Infect Dis ; 19(1): 582, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31277589

RESUMO

BACKGROUND: Varicella zoster virus (VZV) is a highly contagious herpesvirus with potential for nosocomial transmission. However, the importance of nosocomial chickenpox outbreak in China has often been ignored. With the increasing immunocompromised population in China, a thorough review of issues related to nosocomial transmission and the seroprevalence rate of VZV among healthcare workers is necessary. METHODS: Retrospective case finding for nosocomial transmission of chickenpox was conducted between January 1, 2013 and December 31, 2017. Cases were identified based on clinical features compatible with chickenpox. A cross-sectional study on the seroprevalence rate of VZV among healthcare workers (HCWs) was conducted between January 1, 2014 and December 31, 2017. The serum VZV antibodies of 1804 HCWs were measured by enzyme-linked immunosorbent assay (ELISA). The seroprevalence rate of VZV antibodies, the positive predictive value and negative predictive value of self-reported history of varicella were analyzed. The economic impact associated with nosocomial transmission of VZV was also assessed. RESULTS: A total of 8 cases of chickenpox were identified in three nosocomial transmissions, including 4 HCWs who were infected nosocomially. The overall seroprevalence rate of VZV was 88.4%, which significantly increased with age (P < 0.01). The seroprevalence rates of HCWs with different genders and occupations showed no statistically significant differences. The positive and negative predictive values of a self-reported history of varicella were 80.8 and 10.6% respectively. An estimation of 163.3 person-days of work were lost in each nosocomial transmission and 86.7 infection control unit person-hours were required for each outbreak investigation. The cost of VZV IgG ELISA screening was estimated to be 83 USD per nosocomial transmission. CONCLUSIONS: Nosocomial transmission of VZV occurred repeatedly in the hospital setting. An alarming 11.6% of HCWs were seronegative for VZV, which might increase the risk of nosocomial infection and outbreak for other susceptible co-workers and patients. This is especially important in the setting of a teaching hospital where many immunocompromised patients were managed. Furthermore, the positive predictive value of self-reported varicella on seroprevalence rate in our study was lower than those reported in other countries, therefore serological testing of VZV antibodies with subsequent vaccination for all non-immune HCWs should be considered.


Assuntos
Varicela/transmissão , Pessoal de Saúde/estatística & dados numéricos , Infecção pelo Vírus da Varicela-Zoster/transmissão , Adolescente , Adulto , Anticorpos Antivirais/sangue , Varicela/epidemiologia , China/epidemiologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/transmissão , Estudos Transversais , Surtos de Doenças , Suscetibilidade a Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Herpesvirus Humano 3/imunologia , Hospitais de Ensino/estatística & dados numéricos , Humanos , Controle de Infecções , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estudos Soroepidemiológicos , Estudantes de Medicina/estatística & dados numéricos , Infecção pelo Vírus da Varicela-Zoster/epidemiologia
16.
BMC Infect Dis ; 19(1): 587, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31277599

RESUMO

BACKGROUND: In recent years Pakistan has faced frequent measles outbreaks killing hundreds of children despite the availability of vaccine for decades. This study was undertaken to determine the persistence of maternal transferred measles antibody levels in infants before measles vaccination with relation to their feeding practices. METHODS: A cross sectional study was conducted at district Islamabad over 1 year between 1st October 2013 to 30th Sept. 2016. Any infant less than 9 months of age, not suffering from an acute or debilitating illness and not vaccinated was enrolled in the study. After taking written informed consent from parents / guardians, information was collected on a pretested questionnaire. About 3 cc venous blood was taken to quantify any measles IgG antibodies. Data was analyzed by using Epi Info 7.2 version. RESULTS: Three hundred eighty-four infants were enrolled and were divided into three age groups, 1-90, 91-180 and 181-270 days age groups. Mean age of infants was 4.4 months ±3.2 SD. Male to female ratio was 1.2:1. A level of maternal measles IgG antibodies ≥12 U/ml was taken as protective. Of total 384 infants, 91(24%) had protective measles antibody titters (> 12 U/ml). and 65 (73%) of them were on breast milk. Highest antibody levels were found in 1-90 days age group. Analysis showed that 181-270 days aged infants had 3.1875 more odds of having unprotected/ low levels of antibodies against measles than children aged less than 180 days. Age group < 180 days found to be statistically significant with protective IgG levels (OR: 3.1875, P value: < 0.000063). CONCLUSION: Measles protective antibodies were found in infants < 180 days age group. Breast feeding provides early protection against measles. Levels drop down to low levels immediately after birth and then after 06 months. It is, therefore, recommended that measles vaccination should be considered for administration at 6 months or even earlier if measles immunity is desired.


Assuntos
Anticorpos Antivirais/sangue , Aleitamento Materno , Sarampo/imunologia , Leite Humano/imunologia , Adulto , Criança , Estudos Transversais , Feminino , Humanos , Imunoglobulina G/sangue , Lactente , Recém-Nascido , Masculino , Sarampo/epidemiologia , Sarampo/transmissão , Vacina contra Sarampo/imunologia , Paquistão/epidemiologia , Placenta/imunologia , Gravidez , Estudos Soroepidemiológicos , Vacinação/estatística & dados numéricos
17.
Epidemiol Mikrobiol Imunol ; 68(1): 9-14, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31181947

RESUMO

In 2017 chronic hepatitis C (CHC) seems to be a curable disease in most cases. Analysis of epidemiologic data of hepatitis C virus (HCV) infection gained from a primary care office shows how HCV is underdiagnosed in the Czech Republic (CZ). The importance of primary care in screening of HCV infection is shown, as is the necessity of spreading information about this disease between common population and healthcare workers. The aim of the study is to determine seroprevalence of HCV antibodies and HCV ribonucleic acid (RNA) positivity among registered patients with risk factors (RF) in medical history in one physician´s practice. 1620 complete follow-ups of registered clients were accomplished during a 10-month period between 2016 and 2017 in the office of one general practitioner (GP). Amongst those 627 were confirmed to have RF. Each client with RF was tested for HCV antibodies, including detection of HCV RNA via polymerase chain reaction (PCR) method in cases of HCV antibodies positivity. 19 anti HCV positive clients were found, with a prevalence of 3.03%, 5 were HCV RNA positive, with a prevalence of 0.8%.


Assuntos
Hepacivirus , Hepatite C , Adulto , Anticorpos Antivirais/sangue , República Tcheca/epidemiologia , Hepatite C/epidemiologia , Humanos , Reação em Cadeia da Polimerase , Prevalência , RNA Viral/genética , Fatores de Risco , Estudos Soroepidemiológicos
18.
BMC Vet Res ; 15(1): 202, 2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31200717

RESUMO

BACKGROUND: Bovine viral diarrhea virus (BVDV) infects various ungulates and causes reproductive failure in infected goats. BVDV has been detected among goats in the Republic of Korea, but the route of transmission remains unclear. Here, we aimed to investigate whether BVDV-1b circulating among Korean cattle can be transmitted to Korean native goats (Capra aegagrus hircus) and characterize the outcomes of BVDV infection in these goats. RESULTS: Four goats were inoculated intranasally with the Korean noncytopathic (ncp) BVDV-1b strain. Two goats exhibited clinical signs of illness, including coughing and nasal discharge. Nasal swabs and blood were collected to screen for viral RNA and BVDV antibodies. Using the 5'-untranslated region (UTR), viral RNA was detected in the nasal swabs of two goats (Goat 1 and 3) on 12 day post-inoculation (dpi) and in the blood sample of one goat (Goat 1) on 7 and 19 dpi. Using the N-terminal protease (Npro) region, viral RNA was detected in the blood sample of Goat 1 on 7 and 12 dpi. Antibodies to BVDV were detected in Goats 1 and 3 on 16-21 dpi using enzyme-linked immunosorbent assay. Sequence analysis of the virus from nasal swabs and blood samples, which was detected via RT-PCR, using the 5'-UTR and Npro regions led to the identification of the strain as ncp BVDV-1b and revealed changes in the nucleotide sequence of these goats. CONCLUSIONS: Our results indicate that changes in the nucleotide sequence are associated with the establishment of BVDV infection in Korean native goats; these changes may be owing to a process required for the establishment of infection in a new host reservoir. Broadly, these findings highlight the importance of BVDV surveillance in ungulates other than cattle.


Assuntos
Vírus da Diarreia Viral Bovina Tipo 1/genética , Doenças das Cabras/virologia , Infecções por Pestivirus/veterinária , Regiões 5' não Traduzidas , Animais , Anticorpos Antivirais/sangue , Vírus da Diarreia Viral Bovina Tipo 1/imunologia , Vírus da Diarreia Viral Bovina Tipo 1/patogenicidade , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Doenças das Cabras/transmissão , Cabras , Mucosa Nasal/virologia , Infecções por Pestivirus/genética , Infecções por Pestivirus/virologia , RNA Viral/sangue , RNA Viral/genética , República da Coreia , Análise de Sequência de RNA
19.
Nat Med ; 25(6): 962-967, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31160818

RESUMO

Influenza viruses remain a severe threat to human health, causing up to 650,000 deaths annually1,2. Seasonal influenza virus vaccines can prevent infection, but are rendered ineffective by antigenic drift. To provide improved protection from infection, novel influenza virus vaccines that target the conserved epitopes of influenza viruses, specifically those in the hemagglutinin stalk and neuraminidase, are currently being developed3. Antibodies against the hemagglutinin stalk confer protection in animal studies4-6. However, no data exist on natural infections in humans, and these antibodies do not show activity in the hemagglutination inhibition assay, the hemagglutination inhibition titer being the current correlate of protection against influenza virus infection7-9. While previous studies have investigated the protective effect of cellular immune responses and neuraminidase-inhibiting antibodies, additional serological correlates of protection from infection could aid the development of broadly protective or universal influenza virus vaccines10-13. To address this gap, we performed a household transmission study to identify alternative correlates of protection from infection and disease in naturally exposed individuals. Using this study, we determined 50% protective titers and levels for hemagglutination inhibition, full-length hemagglutinin, neuraminidase and hemagglutinin stalk-specific antibodies. Further, we found that hemagglutinin stalk antibodies independently correlated with protection from influenza virus infection.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Adolescente , Adulto , Idoso , Anticorpos Antivirais/sangue , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Testes de Inibição da Hemaglutinação , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Lactente , Recém-Nascido , Influenza Humana/epidemiologia , Masculino , Pessoa de Meia-Idade , Nicarágua/epidemiologia , Pandemias/prevenção & controle , Adulto Jovem
20.
Lancet ; 394(10193): 148-158, 2019 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-31174831

RESUMO

BACKGROUND: Use of oral live-attenuated polio vaccines (OPV), and injected inactivated polio vaccines (IPV) has almost achieved global eradication of wild polio viruses. To address the goals of achieving and maintaining global eradication and minimising the risk of outbreaks of vaccine-derived polioviruses, we tested novel monovalent oral type-2 poliovirus (OPV2) vaccine candidates that are genetically more stable than existing OPVs, with a lower risk of reversion to neurovirulence. Our study represents the first in-human testing of these two novel OPV2 candidates. We aimed to evaluate the safety and immunogenicity of these vaccines, the presence and extent of faecal shedding, and the neurovirulence of shed virus. METHODS: In this double-blind, single-centre phase 1 trial, we isolated participants in a purpose-built containment facility at the University of Antwerp Hospital (Antwerp, Belgium), to minimise the risk of environmental release of the novel OPV2 candidates. Participants, who were recruited by local advertising, were adults (aged 18-50 years) in good health who had previously been vaccinated with IPV, and who would not have any contact with immunosuppressed or unvaccinated people for the duration of faecal shedding at the end of the study. The first participant randomly chose an envelope containing the name of a vaccine candidate, and this determined their allocation; the next 14 participants to be enrolled in the study were sequentially allocated to this group and received the same vaccine. The subsequent 15 participants enrolled after this group were allocated to receive the other vaccine. Participants and the study staff were masked to vaccine groups until the end of the study period. Participants each received a single dose of one vaccine candidate (candidate 1, S2/cre5/S15domV/rec1/hifi3; or candidate 2, S2/S15domV/CpG40), and they were monitored for adverse events, immune responses, and faecal shedding of the vaccine virus for 28 days. Shed virus isolates were tested for the genetic stability of attenuation. The primary outcomes were the incidence and type of serious and severe adverse events, the proportion of participants showing viral shedding in their stools, the time to cessation of viral shedding, the cell culture infective dose of shed virus in virus-positive stools, and a combined index of the prevalence, duration, and quantity of viral shedding in all participants. This study is registered with EudraCT, number 2017-000908-21 and ClinicalTrials.gov, number NCT03430349. FINDINGS: Between May 22 and Aug 22, 2017, 48 volunteers were screened, of whom 15 (31%) volunteers were excluded for reasons relating to the inclusion or exclusion criteria, three (6%) volunteers were not treated because of restrictions to the number of participants in each group, and 30 (63%) volunteers were sequentially allocated to groups (15 participants per group). Both novel OPV2 candidates were immunogenic and increased the median blood titre of serum neutralising antibodies; all participants were seroprotected after vaccination. Both candidates had acceptable tolerability, and no serious adverse events occurred during the study. However, severe events were reported in six (40%) participants receiving candidate 1 (eight events) and nine (60%) participants receiving candidate 2 (12 events); most of these events were increased blood creatinine phosphokinase but were not accompanied by clinical signs or symptoms. Vaccine virus was detected in the stools of 15 (100%) participants receiving vaccine candidate 1 and 13 (87%) participants receiving vaccine candidate 2. Vaccine poliovirus shedding stopped at a median of 23 days (IQR 15-36) after candidate 1 administration and 12 days (1-23) after candidate 2 administration. Total shedding, described by the estimated median shedding index (50% cell culture infective dose/g), was observed to be greater with candidate 1 than candidate 2 across all participants (2·8 [95% CI 1·8-3·5] vs 1·0 [0·7-1·6]). Reversion to neurovirulence, assessed as paralysis of transgenic mice, was low in isolates from those vaccinated with both candidates, and sequencing of shed virus indicated that there was no loss of attenuation in domain V of the 5'-untranslated region, the primary site of reversion in Sabin OPV. INTERPRETATION: We found that the novel OPV2 candidates were safe and immunogenic in IPV-immunised adults, and our data support the further development of these vaccines to potentially be used for maintaining global eradication of neurovirulent type-2 polioviruses. FUNDING: Bill & Melinda Gates Foundation.


Assuntos
Imunogenicidade da Vacina , Vacina Antipólio Oral/efeitos adversos , Vacina Antipólio Oral/imunologia , Poliovirus/imunologia , Adulto , Anticorpos Antivirais/sangue , Método Duplo-Cego , Fezes/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Poliomielite/prevenção & controle , Vacina Antipólio Oral/administração & dosagem , RNA Viral/análise , Método Simples-Cego , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/efeitos adversos , Vacinas Atenuadas/imunologia , Virulência/imunologia , Eliminação de Partículas Virais/imunologia , Adulto Jovem
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