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1.
PLoS Negl Trop Dis ; 16(2): e0010124, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35143490

RESUMO

An increasing number of countries are committing to meet the global target to eliminate human deaths from dog-mediated rabies by 2030. Mass dog vaccination is central to this strategy. To interrupt rabies transmission from dogs to humans, the World Health Organization recommends that vaccination campaigns should be carried out every year in all dog-owning communities vaccinating 70% of their susceptible dogs. Monitoring and evaluation of dog vaccination campaigns are needed to measure progress towards elimination. In this study, we measured the delivery performance of large-scale vaccination campaigns implemented in 25 districts in south-east Tanzania from 2010 until 2017. We used regression modelling to infer the factors associated with, and potentially influencing the successful delivery of vaccination campaigns. During 2010-2017, five rounds of vaccination campaigns were carried out, vaccinating in total 349,513 dogs in 2,066 administrative vaccination units (rural villages or urban wards). Progressively more dogs were vaccinated over the successive campaigns. The campaigns did not reach all vaccination units each year, with only 16-28% of districts achieving 100% campaign completeness (where all units were vaccinated). During 2013-2017 when vaccination coverage was monitored, approximately 20% of vaccination units achieved the recommended 70% coverage, with average coverage around 50%. Campaigns were also not completed at annual intervals, with the longest interval between campaigns being 27 months. Our analysis revealed that districts with higher budgets generally achieved higher completeness, with a twofold difference in district budget increasing the odds of a vaccination unit being reached by a campaign by slightly more than twofold (OR: 2.29; 95% CI: 1.69-3.09). However, higher budgets did not necessarily result in higher coverage within vaccination units that were reached. We recommend national programs regularly monitor and evaluate the performance of their vaccination campaigns, so as to identify factors hindering their effective delivery and to guide remedial action.


Assuntos
Doenças do Cão/prevenção & controle , Vacina Antirrábica/administração & dosagem , Vírus da Raiva/imunologia , Raiva/prevenção & controle , Animais , Doenças do Cão/epidemiologia , Doenças do Cão/virologia , Cães , Feminino , Promoção da Saúde , Modelos Lineares , Masculino , Raiva/epidemiologia , Raiva/virologia , Vírus da Raiva/genética , Tanzânia/epidemiologia , Vacinação
2.
J Immunol Methods ; 492: 112939, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33309752

RESUMO

The potency of all modern tissue culture human rabies vaccines is measured based on the National Institute of Health (NIH) potency test that is laborious, time-consuming, involves large test variations and requires sacrifice of large number of animals. To circumvent these limitations, several researchers and WHO expert working groups have discussed development of alternative in vitro methods to replace the NIH potency test. Although several immunochemical methods have been proposed to quantify rabies glycoprotein (G-protein) using multiple murine monoclonal antibodies, we report an In vitro competitive inhibition ELISA (CIA) method based on the use of a neutralizing rabies glycoprotein site III directed novel therapeutic human rabies monoclonal antibody (RAB1) that shows equivalence to the mice NIH potency test in recognition of neutralization site of the glycoprotein. In vitro potency testing of WHO 7th International Standard for rabies vaccine (IS) by CIA using RAB1 and In-house reference standard (IHRS) as a standard to assess its suitability for the assessment of validation parameters showed accurate and precise values with <15% coefficient variance. The method was validated using 5PL standard curve with linearity r2 > 0.98 and LLOQ of 0.125 IU/mL indicating sensitivity of the method. The method was found to be precise, robust and accurate to quantitate intact rabies glycoprotein in final vaccine and showed a strong correlation (Pearson's r = 0.81) with the NIH potency values of licensed Vero cell rabies vaccine. The CIA test using RAB1 was able to accurately quantitate degradation of rabies vaccine and assess loss in antigenicity of lyophilized and reconstituted liquid rabies vaccine under thermal stress conditions. The method was able to differentiate between potent and reduced potency vaccine samples. The new in vitro competitive inhibition ELISA method using RAB1 thus can be a valid alternative to the NIH test.


Assuntos
Antígenos Virais/imunologia , Vacina Antirrábica/imunologia , Vírus da Raiva/imunologia , Raiva/prevenção & controle , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Monoclonais/imunologia , Antígenos Virais/administração & dosagem , Chlorocebus aethiops , Ensaio de Imunoadsorção Enzimática/métodos , Mapeamento de Epitopos/métodos , Humanos , Profilaxia Pós-Exposição/métodos , Raiva/imunologia , Raiva/virologia , Vacina Antirrábica/administração & dosagem , Potência de Vacina , Células Vero , Proteínas do Envelope Viral/administração & dosagem
3.
Euro Surveill ; 25(38)2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32975187

RESUMO

BackgroundThe risk of contracting rabies is low for travellers. However, the number of Dutch travellers potentially exposed abroad following an animal-associated injury and needing post-exposure prophylaxis (PEP) has increased, resulting in increased costs.AimHere, we evaluated the costs and the cost-effectiveness of different pre- and post-exposure interventions in the Netherlands, taking into account the 2018 World Health Organization (WHO) recommendations for the prevention of rabies.MethodsA decision tree-based economic model was constructed. We calculated and compared the cost of different WHO pre-exposure prophylaxis (PrEP) recommendations, intramuscular vs intradermal vaccination and PEP subsequent to increased vaccination coverage in risk groups. We estimated cost-effectiveness, expressed as incremental costs per rabies immunoglobulin (RIG) administration averted, using a societal perspective. Statistical uncertainty regarding number of travellers and vaccination coverage was assessed.ResultsTotal costs at the national level were highest using previous WHO recommendations from 2012, estimated at EUR 15.4 million annually. Intradermal vaccinations in combination with the current recommendations led to the lowest costs, estimated at EUR 10.3 million. Higher vaccination uptake resulted in higher overall costs. The incremental costs per RIG administration averted varied from EUR 21,300-46,800.ConclusionsThe change in rabies PrEP and PEP recommendations in 2018 reduced total costs. Strategies with increased pre-travel vaccination uptake led to fewer RIG administrations and fewer vaccinations after exposure but also to higher total costs. Although larger scale intradermal administration of rabies vaccine can reduce total costs of PrEP and can positively influence vaccination uptake, it remains a costly intervention.


Assuntos
Profilaxia Pós-Exposição/economia , Profilaxia Pré-Exposição/economia , Vacina Antirrábica/administração & dosagem , Vacina Antirrábica/economia , Vírus da Raiva/imunologia , Raiva/prevenção & controle , Animais , Análise Custo-Benefício , Humanos , Modelos Econômicos , Profilaxia Pós-Exposição/estatística & dados numéricos , Profilaxia Pré-Exposição/estatística & dados numéricos , Raiva/imunologia , Vacinação/economia , Vacinação/métodos
4.
PLoS Negl Trop Dis ; 13(12): e0007824, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31825968

RESUMO

BACKGROUND: Domestic carnivores can introduce rabies into disease-free countries or areas if they are incubating the disease and transported during the pre-symptomatic period. For pets moved into the European Union, the European Commission decided to establish a system of community approval of laboratories willing to carry out the rabies serological controls to guarantee an effective control system. As the specific institute to coordinate the approval of the laboratories, designated by the European Commission in 2000, our laboratory organizes annual proficiency tests (PT) for laboratories already agreed or willing to be agreed to perform rabies serological controls (by detecting rabies virus neutralizing antibodies only) in the frame of international trade. METHODOLOGY/PRINCIPAL FINDINGS: The assessment criteria of this PT rely on the analysis of the specificity and the intra-laboratory consistency. The approach used to evaluate the degree of laboratory consistency is based on the use of compiled data obtained from previous PT campaigns, and is measured by the quality of a regression model. By using historical data for calculating assigned values and associated standard deviations, instead of values obtained from only one campaign, they became robust without any additional statistical treatment. In the present paper, more than 800 historical values were compiled for each of the regression parameters. CONCLUSIONS/SIGNIFICANCE: Since the beginning of these PT schemes in 1999, the overall percentage of failing laboratories remained stable over the years (4.1%) while the number of participants increased to 79 in 2018. This highlighted the robustness and the consistency of the statistical analyses used to assess the laboratory's performance over the years. The improvements carried out and the consistency of our statistical analyses have resulted in the compliance of the rabies serology PT with the ISO/IEC 17043 and ISO 13528:2015 International Standards.


Assuntos
Anticorpos Antivirais/sangue , Doenças do Cão/diagnóstico , Ensaio de Proficiência Laboratorial , Vírus da Raiva/imunologia , Raiva/veterinária , Testes Sorológicos/métodos , Animais , Cães , União Europeia , Testes de Neutralização/métodos , Raiva/diagnóstico
5.
PLoS Negl Trop Dis ; 13(5): e0007377, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31116732

RESUMO

We present a new modeling tool that can be used to maximize the impact of canine rabies management resources that are available at the local level. The model is accessible through a web-based interface that allows for flexibility in the management strategies that can be investigated. Rabies vaccination, sterilization, chemo-contraception, and euthanasia can be specified and limited to specific demographic groups. Additionally, we allowed for considerable complexity in the specification of management costs. In many areas, the costs of contacting additional dogs increases as management effort increases, and this can have important strategic implications. We illustrated the application of the model by examining several alternative management strategies in an area of Mpumalanga Province, South Africa. Our results based on this dog population suggested that puppies should be vaccinated and sterilization would not be optimal if the spatial extent of management is not large (and perhaps not even then). Furthermore, given a sufficient budget, it was evident that vaccination campaigns should be repeated annually.


Assuntos
Doenças do Cão/prevenção & controle , Raiva/veterinária , Animais , Doenças do Cão/economia , Doenças do Cão/virologia , Cães , Modelos Econômicos , Raiva/economia , Raiva/prevenção & controle , Vacina Antirrábica/administração & dosagem , Vírus da Raiva/genética , Vírus da Raiva/imunologia , África do Sul , Vacinação
6.
Zoonoses Public Health ; 66(5): 533-539, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30688040

RESUMO

Contact with infected saliva through the bite of a rabid animal is the main route of infection with the rabies Lyssavirus in humans. Although a few individuals have survived the infection, rabies remains the most lethal zoonotic infection worldwide. Over the last century, the dogma that rabies is invariably fatal has been challenged by the survival and recovery of infected animals. In humans, 11 studies have found rabies virus-specific antibodies in unvaccinated individuals exposed to rabies virus reservoir species, suggesting the possibility of asymptomatic rabies virus infection, contact with non-infectious virus or exposure to the virus without viral replication. Two of these studies were conducted in Arctic hunters. Considering the extensive exposure of Nunavik's Inuit to potentially infected animals through hunting, trapping, skinning and the preparation of Arctic carnivores, we analysed archived serum samples from the 2004 Nunavik Inuit Health Survey for the presence of rabies virus-neutralizing antibodies (rVNA) in this sub-population. A total of 196 participants who were considered at highest risk for exposure to rabies virus were targeted. Serum samples were tested for the presence of rVNA using a variation of the fluorescent antibody virus neutralization test, an assay recommended for the quantification of neutralizing antibody titres following vaccination. Our study identified two seropositive individuals among the 196 participants but a review of their medical record and a phone interview revealed previous vaccination. Our results do not provide evidence for naturally acquired rVNA in Nunavik's Inuit population.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Inuíte , Vírus da Raiva/imunologia , Raiva/veterinária , Zoonoses/epidemiologia , Adolescente , Adulto , Idoso , Animais , Canadá/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Raiva/epidemiologia , Adulto Jovem
7.
Jpn J Infect Dis ; 72(2): 99-105, 2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30381684

RESUMO

The coverage of rabies vaccinations has been reported at 70-80% of dogs in annual reports. However, there are still outbreaks of rabies among humans and dogs in Thailand, thus indicating the necessity of ensuring seroprevalence in vaccinated dogs and efficacy of human immunization. A cost effective easy competitive enzyme-linked immunosorbent assay (CEE-cELISA) was developed here for monitoring protective immunity against the rabies virus in human and dog serum samples using monoclonal antibody clone 1-46-12, which recognizes a conformational epitope of the rabies G protein. The ELISA plate is coated with the whole viral antigen from a commercial vaccine. The serotiter measured by the CEE-cELISA and by the gold standard assay (rapid fluorescent focus inhibition test), detecting the neutralizing antibody, showed a strong correlation, with an R value of 0.958 and 0.931 in humans and dogs, respectively. These correlations were detected in the serum samples from humans and dogs at antibody concentrations up to 100 and 10 IU/ml, respectively. This CEE-cELISA could be an alternative assay for evaluating mass rabies vaccination rapidly at a low cost as well as for detecting antirabies antibodies in the serum of not only humans but also other animal species.


Assuntos
Anticorpos Antivirais/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Vírus da Raiva/imunologia , Animais , Anticorpos Monoclonais/imunologia , Antígenos Virais/imunologia , Análise Custo-Benefício , Cães , Ensaio de Imunoadsorção Enzimática/economia , Humanos , Estudos Soroepidemiológicos , Soro/imunologia , Tailândia
8.
Lancet Infect Dis ; 19(1): 102-111, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30472178

RESUMO

BACKGROUND: Tens of thousands of people die from dog-mediated rabies annually. Deaths can be prevented through post-exposure prophylaxis for people who have been bitten, and the disease eliminated through dog vaccination. Current post-exposure prophylaxis use saves many lives, but availability remains poor in many rabies-endemic countries due to high costs, poor access, and supply. METHODS: We developed epidemiological and economic models to investigate the effect of an investment in post-exposure prophylaxis by Gavi, the Vaccine Alliance. We modelled post-exposure prophylaxis use according to the status quo, with improved access using WHO-recommended intradermal vaccination, with and without rabies immunoglobulin, and with and without dog vaccination. We took the health provider perspective, including only direct costs. FINDINGS: We predict more than 1 million deaths will occur in the 67 rabies-endemic countries considered from 2020 to 2035, under the status quo. Current post-exposure prophylaxis use prevents approximately 56 000 deaths annually. Expanded access to, and free provision of, post-exposure prophylaxis would prevent an additional 489 000 deaths between 2020 and 2035. Under this switch to efficient intradermal post-exposure prophylaxis regimens, total projected vaccine needs remain similar (about 73 million vials) yet 17·4 million more people are vaccinated, making this an extremely cost-effective method, with costs of US$635 per death averted and $33 per disability-adjusted life-years averted. Scaling up dog vaccination programmes could eliminate dog-mediated rabies over this time period; improved post-exposure prophylaxis access remains cost-effective under this scenario, especially in combination with patient risk assessments to reduce unnecessary post-exposure prophylaxis use. INTERPRETATION: Investing in post-exposure vaccines would be an extremely cost-effective intervention that could substantially reduce disease burden and catalyse dog vaccination efforts to eliminate dog-mediated rabies. FUNDING: World Health Organization.


Assuntos
Doenças do Cão/prevenção & controle , Profilaxia Pós-Exposição/economia , Vacina Antirrábica/economia , Vírus da Raiva/imunologia , Raiva/epidemiologia , Raiva/prevenção & controle , Vacinação/economia , Animais , Mordeduras e Picadas/virologia , Pré-Escolar , Análise Custo-Benefício/métodos , Cães , Doenças Endêmicas/prevenção & controle , Feminino , Humanos , Imunoglobulinas/uso terapêutico , Incidência , Masculino , Modelos Econômicos , Profilaxia Pós-Exposição/métodos , Anos de Vida Ajustados por Qualidade de Vida , Raiva/mortalidade , Raiva/virologia , Vacina Antirrábica/uso terapêutico , Vírus da Raiva/isolamento & purificação , Organização Mundial da Saúde
9.
Rev Soc Bras Med Trop ; 51(1): 39-43, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29513840

RESUMO

INTRODUCTION: Rabies is an acute zoonotic disease, caused by a rhabdovirus that can affect all mammals, and is commonly transmitted by the bite of a rabid animal. The definitive diagnosis is laboratorial, by the Fluorescent Antibody Test (FAT) as a quick test and Mouse Inoculation Test (MIT) as a confirmatory test (gold standard). Studies conducted over the past three decades indicate that MIT and Virus Isolation in Cell Culture (VICC) can provide the same effectiveness, the latter being considered superior in bioethics and animal welfare. The aim of this study was to compare VICC with MIT, in terms of accuracy, biosafety and occupational health, supply and equipment costs, bioethics and animal welfare, in a Brazilian public health lab. METHODS: We utilized 400 samples of animal neurological tissue to compare the performance of VICC against MIT. The variables analyzed were accuracy, biosafety and occupational health, time spent in performing the tests, supply and equipment costs, bioethics and animal welfare evaluation. RESULTS: Both VICC and MIT had almost the same accuracy (99.8%), although VICC presented fewer risks regarding biosafety and mental health of the technicians, and reduced time between inoculation and obtaining the results (approximately 22 days less). In addition, VICC presented lower supply costs (86.5% less), equipment costs (32.6% less), and the advantage of not using animals. CONCLUSIONS: These results confirm that VICC can replace MIT, offering the same accuracy and better features regarding cost, results, biosafety and occupational health, and bioethics and animal welfare.


Assuntos
Temas Bioéticos , Técnicas de Cultura de Células/métodos , Contenção de Riscos Biológicos , Imunofluorescência/métodos , Saúde Ocupacional , Vírus da Raiva/imunologia , Raiva/diagnóstico , Bem-Estar do Animal , Animais , Técnicas de Cultura de Células/economia , Custos e Análise de Custo , Imunofluorescência/economia , Camundongos , Vírus da Raiva/isolamento & purificação , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade
10.
Vet Microbiol ; 216: 107-118, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29519504

RESUMO

Following the last animal rabies outbreak in Greece in 2012, Oral Rabies Vaccination (ORV) campaigns of red foxes (Vulpes vulpes) were conducted in order to halt the spread of the disease, as widely and effectively have also been implemented in other countries. The present study aims to report the main outcomes following the first Greek ORV campaigns during autumn 2013, 2014, 2015 and spring 2016, to assess their effectiveness and to investigate factors potentially related to their success. Blood samples, mandible bones and teeth, derived by 452 foxes, were tested for rabies antibody titration, animal age determination and tetracycline (TTC) detection. The laboratory results obtained were statistically analyzed. High seroprevalence and TTC detection rates were obtained following the autumn campaigns studied, while these rates were significantly reduced following the spring campaign. The year or the season of the vaccination campaign, the estimated age group of the animal and the geographical Regional Unit (RU), where the animal was hunted, were identified as important factors. On the contrary, no significance could be ascertained for TTC detection based on exclusively previous uptake, use of filter paper, blood sample type and quality, as well as sex of animal. Based on the monitoring results achieved, the first ORV campaigns conducted in the country can be generally considered to be satisfactory. No positives cases were detected since May 2014. Seasonal, geographical parameters and factors related to fox ecology may interfere with monitoring results and should be always considered when planning future ORV programs.


Assuntos
Programas de Imunização , Vacina Antirrábica/administração & dosagem , Raiva/veterinária , Vacinação , Administração Oral , Animais , Raposas/virologia , Grécia/epidemiologia , Raiva/epidemiologia , Raiva/prevenção & controle , Raiva/virologia , Vacina Antirrábica/efeitos adversos , Vacina Antirrábica/imunologia , Vírus da Raiva/imunologia , Estações do Ano , Soroconversão , Estudos Soroepidemiológicos , Tetraciclina/sangue
11.
Rev. Soc. Bras. Med. Trop ; 51(1): 39-43, Jan.-Feb. 2018. tab
Artigo em Inglês | LILACS | ID: biblio-897046

RESUMO

Abstract INTRODUCTION: Rabies is an acute zoonotic disease, caused by a rhabdovirus that can affect all mammals, and is commonly transmitted by the bite of a rabid animal. The definitive diagnosis is laboratorial, by the Fluorescent Antibody Test (FAT) as a quick test and Mouse Inoculation Test (MIT) as a confirmatory test (gold standard). Studies conducted over the past three decades indicate that MIT and Virus Isolation in Cell Culture (VICC) can provide the same effectiveness, the latter being considered superior in bioethics and animal welfare. The aim of this study was to compare VICC with MIT, in terms of accuracy, biosafety and occupational health, supply and equipment costs, bioethics and animal welfare, in a Brazilian public health lab. METHODS: We utilized 400 samples of animal neurological tissue to compare the performance of VICC against MIT. The variables analyzed were accuracy, biosafety and occupational health, time spent in performing the tests, supply and equipment costs, bioethics and animal welfare evaluation. RESULTS: Both VICC and MIT had almost the same accuracy (99.8%), although VICC presented fewer risks regarding biosafety and mental health of the technicians, and reduced time between inoculation and obtaining the results (approximately 22 days less). In addition, VICC presented lower supply costs (86.5% less), equipment costs (32.6% less), and the advantage of not using animals. CONCLUSIONS: These results confirm that VICC can replace MIT, offering the same accuracy and better features regarding cost, results, biosafety and occupational health, and bioethics and animal welfare.


Assuntos
Animais , Raiva/diagnóstico , Vírus da Raiva/imunologia , Saúde Ocupacional , Imunofluorescência/métodos , Técnicas de Cultura de Células/métodos , Contenção de Riscos Biológicos , Temas Bioéticos , Vírus da Raiva/isolamento & purificação , Bem-Estar do Animal , Reprodutibilidade dos Testes , Fatores de Risco , Imunofluorescência/economia , Sensibilidade e Especificidade , Técnicas de Cultura de Células/economia , Custos e Análise de Custo , Camundongos
12.
Vaccine ; 36(6): 811-817, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29325820

RESUMO

A safety requirement for live vaccines is investigating possible shedding in recipients since the presence of replication competent vaccine in secretions could result in direct and indirect horizontal transmission. This is especially relevant for oral rabies vaccine baits that are deliberately distributed into the environment. In the current study, survival of an oral rabies virus vaccine, SPBN GASGAS, was examined in excretions from different target and non-target species; red fox, raccoon dog, small Indian mongoose, raccoon, striped skunk, domestic dog, domestic cat and domestic pig. Saliva - and (pooled) fecal samples collected at different time points after oral administration of the vaccine strain were examined for the presence of viral RNA (rt-PCR). All PCR-positive and a subset of PCR-negative samples were subsequently investigated for the presence of infectious virus by isolation in cell culture (RTCIT). Up to 7 days post vaccine administration viral RNA could be detected in 50 of 758 fecal samples but no infectious virus was detected in any of the examined PCR-positive fecal samples. In contrast, RNA-fragments were detected in 248 of 1053 saliva swabs for an extended period (up to 10 days) after vaccine administration, but viable virus was only present during the first hours post vaccine administration in 38 samples. No infectious vaccine virus was isolated in saliva swabs taken 24 h or more after vaccine administration. Hence, no active shedding of the vaccine virus SPBN GASGAS after oral administration occurred and the virus isolated during the initial hours was material originally administered and not a result of virus replication within the host. Thus, potential horizontal transmission of this vaccine virus is limited to a short period directly after vaccine bait uptake. It can be concluded that the environmental risks associated with shedding after distributing vaccine baits containing SPBN GASGAS are negligible.


Assuntos
Vacina Antirrábica/imunologia , Vírus da Raiva/imunologia , Raiva/imunologia , Raiva/virologia , Eliminação de Partículas Virais , Administração Oral , Animais , Raposas , Imunização , Mephitidae , Raiva/prevenção & controle , Vacina Antirrábica/administração & dosagem , Guaxinins , Suínos
14.
Afr Health Sci ; 16(1): 123-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27358622

RESUMO

BACKGROUND: Rabies causes 55, 000 annual human deaths globally and about 10,000 people are exposed annually in Nigeria. Diagnosis of animal rabies in most African countries has been by direct microscopic examination. In Nigeria, the Seller's stain test (SST) was employed until 2009. Before then, both SST and dFAT were used concurrently until the dFAT became the only standard method. OBJECTIVE: This study was designed to assess the sensitivity and specificity of the SST in relation to the 'gold standard' dFAT in diagnosis of rabies in Nigeria. METHODS: A total of 88 animal specimens submitted to the Rabies National Reference Laboratory, Nigeria were routinely tested for rabies by SST and dFAT. RESULTS: Overall, 65.9% of the specimens were positive for rabies by SST, while 81.8% were positive by dFAT. The sensitivity of SST in relation to the gold standard dFAT was 81.0% (95% CIs; 69.7% - 88.6%), while the specificity was 100% (95% CIs; 76% - 100%). CONCLUSION: The relatively low sensitivity of the SST observed in this study calls for its replacement with the dFAT for accurate diagnosis of rabies and timely decisions on administration of PEP to prevent untimely deaths of exposed humans.


Assuntos
Anticorpos Antivirais/análise , Técnica Direta de Fluorescência para Anticorpo/métodos , Vírus da Raiva/imunologia , Vírus da Raiva/isolamento & purificação , Raiva/diagnóstico , Coloração e Rotulagem , Animais , Doenças do Cão , Cães , Humanos , Nigéria , Sensibilidade e Especificidade
15.
Infect Disord Drug Targets ; 15(1): 13-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25809623

RESUMO

Rabies is a zoonose affecting wild and domestic animals and transmitted to humans through bites or scratches, causing over 60,000 human deaths, annually. The disease results from the transmission of a neurotropic virus leading to invariably deadly encephalitis. The post-exposure prophylaxis consists of careful washing and disinfection of the wound, antibiotherapy and tetanus prophylaxis when needed. Furthermore, rabies vaccine and rabies immunoglobulin [RIG] administration should be applied according to the type of wound, and the animal involved, according to the WHO protocols that are regularly updated. Unfortunately it is sometimes difficult to obtain RIG in some countries due to their high cost, leading to suboptimal treatment and possible death. Also, observance can be weak, due to the number of repeated visits required with protocols [up to five visits over 28 days]. These limitations justify research on new vaccines which were not conclusive at the moment. New RIGs are under development, including a monoclonal antibody cocktail which is more promising in a near future. Finally, vaccination protocols are in the way of being shortened in given conditions. Further studies are needed to validate these new practices.


Assuntos
Imunização Passiva , Profilaxia Pós-Exposição , Vacina Antirrábica/uso terapêutico , Vírus da Raiva/imunologia , Raiva/prevenção & controle , Animais , Humanos , Imunização Passiva/economia , Organização Mundial da Saúde , Zoonoses
16.
Hum Vaccin Immunother ; 10(10): 2805-12, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25483635

RESUMO

The Zagreb regimen has been used for 20 years in various countries. In China, until 2010, the Zagreb schedule was only approved for purified chick embryo cell vaccine (PCECV) and purified Vero cell rabies vaccines (PVRV). In this phase III clinical trial, we aimed to demonstrate the safety and immunogenic non-inferiority of the Zagreb regimen compared with the Essen regimen in healthy adult Chinese immunized with PCECV (Rabipur®). The study enrolled 825 subjects aged 18 to 50 years; serum samples were collected on Days 0, 7, 14, 42, and at 13 months to assess rabies virus neutralizing antibody (RVNA) concentrations. Solicited and unsolicited local and systemic reactions were recorded for 6 days following the day of vaccination, and collected throughout the entire study period (Day 1 until Month 13). The Zagreb regimen was non-inferior to the Essen regimen with regard to RVNA concentrations after 7, 14, and 42 days, and 13 months of immunization. The non-inferiority of seroconversion was established at Days 14 and 42. The incidence of local and systemic reactions was similar between groups, and mostly of mild or moderate severity. Vaccine-related adverse events occurred more frequently in the Essen group than in the Zagreb group. Vaccination with PCECV under a 2-1-1 regimen is as safe and immunogenic as under the traditional 5-dose Essen regimen for rabies post-exposure prophylaxis, and is a more cost-effective option, has a more practical vaccination schedule, and can potentially increase compliance.


Assuntos
Esquemas de Imunização , Vacina Antirrábica/administração & dosagem , Vacina Antirrábica/imunologia , Raiva/prevenção & controle , Vacinação , Adolescente , Adulto , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Embrião de Galinha , China , Chlorocebus aethiops , Análise Custo-Benefício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Profilaxia Pós-Exposição , Vírus da Raiva/imunologia , Células Vero , Adulto Jovem
17.
Arch Virol ; 159(8): 1987-93, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24590567

RESUMO

The measurement of neutralizing antibodies induced by the glycoprotein of rabies virus is indispensable for assessing the level of neutralizing antibodies in animals or humans. A rapid fluorescent focus inhibition test (RFFIT) has been approved by WHO and is the most widely used method to measure the virus-neutralizing antibody content in serum, but a rapid test system would be of great value to screen large numbers of serum samples. To develop and evaluate a latex agglutination test (LAT) for measuring rabies virus antibodies, a recombinant glycoprotein was expressed in an insect cell system and purified, and the protein was coated onto latex beads at concentrations of 0.1, 0.25, 0.5, 0.75, and 1 mg/ml to find out the optimal concentration for coating latex beads. It was found that 0.5 mg/ml of recombinant protein was optimal for coating latex beads, and this concentration was used to sensitize the latex beads for screening of dog serum samples. Grading of LAT results was done with standard reference serum with known antibody titers. A total of 228 serum samples were tested, out of which 145 samples were positive by both RFFIT and LAT, and the specificity was found to be 100 %. In RFFIT, 151 samples were positive, the sensitivity was found to be 96.03 %, and the accuracy/concordance was found to be 97.39 %. A rapid field test-a latex agglutination test (LAT)-was developed and evaluated for rabies virus antibody assessment using recombinant glycoprotein of rabies virus expressed in an insect cell system.


Assuntos
Anticorpos Antivirais/sangue , Doenças do Cão/sangue , Testes de Fixação do Látex/métodos , Raiva/sangue , Raiva/veterinária , Animais , Anticorpos Antivirais/imunologia , Linhagem Celular , Doenças do Cão/diagnóstico , Doenças do Cão/imunologia , Doenças do Cão/virologia , Cães , Glicoproteínas/química , Glicoproteínas/genética , Glicoproteínas/imunologia , Humanos , Raiva/diagnóstico , Raiva/imunologia , Raiva/virologia , Vírus da Raiva/genética , Vírus da Raiva/imunologia , Vírus da Raiva/isolamento & purificação , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Virais/química , Proteínas Virais/genética , Proteínas Virais/imunologia
18.
Transbound Emerg Dis ; 61(2): 140-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22984914

RESUMO

Vampire bat rabies causes significant impacts within its endemic range in Mexico. These impacts include livestock mortality, animal testing costs, post-exposure prophylaxis costs, and human mortality risk. Mitigation of the impacts can be achieved by vaccinating livestock and controlling vampire bat populations. A benefit-cost analysis was performed to examine the economic efficiency of these methods of mitigation, and Monte Carlo simulations were used to examine the impact that uncertainty has on the analysis. We found that livestock vaccination is efficient, with benefits being over six times higher than costs. However, bat control is inefficient because benefits are very unlikely to exceed costs. It is concluded that when these mitigation methods are judged by the metric of economic efficiency, livestock vaccination is desirable but bat control is not.


Assuntos
Doenças dos Bovinos/economia , Quirópteros/virologia , Surtos de Doenças/economia , Vacina Antirrábica/economia , Vírus da Raiva/imunologia , Raiva/veterinária , Vacinação/veterinária , Animais , Bovinos , Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/virologia , Análise Custo-Benefício , Surtos de Doenças/prevenção & controle , Surtos de Doenças/veterinária , Reservatórios de Doenças/veterinária , Reservatórios de Doenças/virologia , México/epidemiologia , Raiva/economia , Raiva/prevenção & controle , Raiva/virologia , Vacina Antirrábica/administração & dosagem , Vacinação/economia
19.
Vaccine ; 31(17): 2207-13, 2013 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-23499602

RESUMO

ONRAB is a rabies glycoprotein recombinant human adenovirus type 5 oral vaccine developed for application in baits to control rabies in wildlife populations. Prior to widespread use of ONRAB, both the safety and effectiveness of this vaccine required investigation. While previous research has focused on field performance and the persistence and pathogenicity of ONRAB in captive animals, we sought to examine persistence and shedding of ONRAB in populations of free-ranging target and non-target mammals. We collected oral and rectal swab samples from 84 red foxes, 169 striped skunks, and 116 raccoons during 2007 and 2008 in areas where ONRAB vaccine baits were distributed. We also analyzed 930 tissue samples, 135 oral swab and 138 rectal swab samples from 155 non-target small mammals from 10 species captured during 2008 at sites treated with high densities of ONRAB vaccine baits. Samples were screened for the presence and quantity of ONRAB DNA using quantitative real-time PCR. None of the samples that we analyzed from target and non-target species contained quantities of ONRAB greater than 10(3)EU/mL of ONRAB DNA which is a limit that has previously been applied to assess viral shedding. This study builds on similar research and suggests that replication of ONRAB in animals is short-lived and the likelihood of horizontal transmission to other organisms is low.


Assuntos
Mamíferos/imunologia , Vacina Antirrábica/administração & dosagem , Vacina Antirrábica/imunologia , Raiva/imunologia , Administração Oral , Animais , Anticorpos Antivirais/imunologia , Humanos , Ontário , Raiva/prevenção & controle , Vacina Antirrábica/efeitos adversos , Vacina Antirrábica/genética , Vírus da Raiva/genética , Vírus da Raiva/imunologia , Vírus da Raiva/isolamento & purificação , Vírus da Raiva/fisiologia , Reação em Cadeia da Polimerase em Tempo Real , Vacinas de DNA/administração & dosagem , Vacinas de DNA/efeitos adversos , Vacinas de DNA/genética , Vacinas de DNA/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/efeitos adversos , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Eliminação de Partículas Virais
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