Diagnosis Of Rabies Research Articles

Bat rabies in France: a 24-year retrospective epidemiological study.

Since bat rabies surveillance was first implemented in France in 1989, 48 autochthonous rabies cases without human contamination have been reported using routine diagnosis methods. In this retrospective study, data on bats submitted for rabies testing were analysed in order to better understand the epidemiology of EBLV-1 in bats in France and to investigate some epidemiological trends. Of the 3176 bats submitted for rabies diagnosis from 1989 to 2013, 1.96% (48/2447 analysed) were diagnosed positive. Among the twelve recognised virus species within the Lyssavirus genus, two species were isolated in France. 47 positive bats were morphologically identified as Eptesicus serotinus and were shown to be infected by both the EBLV-1a and the EBLV-1b lineages. Isolation of BBLV in Myotis nattereri was reported once in the north-east of France in 2012. The phylogenetic characterisation of all 47 French EBLV-1 isolates sampled between 1989 and 2013 and the French BBLV sample against 21 referenced partial nucleoprotein sequences confirmed the low genetic diversity of EBLV-1 despite its extensive geographical range. Statistical analysis performed on the serotine bat data collected from 1989 to 2013 showed seasonal variation of rabies occurrence with a significantly higher proportion of positive samples detected during the autumn compared to the spring and the summer period (34% of positive bats detected in autumn, 15% in summer, 13% in spring and 12% in winter). In this study, we have provided the details of the geographical distribution of EBLV-1a in the south-west of France and the north-south division of EBLV-1b with its subdivisions into three phylogenetic groups: group B1 in the north-west, group B2 in the centre and group B3 in the north-east of France.

Perceived barriers to the adoption of alternatives to laboratory animal use for rabies diagnosis.

The use of laboratory animals is still common practice, but some uses can be replaced by alternative methods, such as Virus Isolation in Cell Culture (VICC) instead of the Mouse Inoculation Test (MIT) for rabies diagnosis. The objective of this work was to describe current rabies diagnosis methods in Brazil and other countries, and the constraints associated with replacing this use of mice with alternative methods. Nine out of 12 Brazilian and 14 out of 43 non-Brazilian respondents reported that they currently used the MIT. Respondents in countries other than Brazil, male respondents, and those already employing in vitro methods for rabies diagnosis, expressed higher levels of support for the use of alternatives. The most frequently reported constraints associated with the use of alternatives were lack of laboratory facilities, equipment and materials (cited 17 times by respondents), and lack of financial resources (cited 15 times). The results indicate that many laboratories continue to use mice for rabies diagnosis. The proportion of laboratories that use mice appears to be especially high in Brazil, despite animal protection laws and technical guidelines that favour the use of alternatives. The barriers to the adoption of alternative methods identified in the current study provide a basis for facilitating changes in Brazil and elsewhere.

Comparison of direct, Rapid Immunohistochemical Test Performance with Direct Fluorescent Antibody Test for rabies diagnosis in Ethiopia

Background: Rabies continues to be a persistent and major public health problem for many developing countries. Rapid and accurate laboratory diagnosis is one of the basic elements in rabies control strategies. However, Laboratory diagnosis for animal and human rabies is severely constrained in much of the developing world including Ethiopia where rabies is endemic. Objective: To evaluate the performance of Direct, Rapid Immunohistochemical Test for rabies antigen detection from clinical samples in comparison with the Direct Fluorescent Antibody, gold-standard test. Method: The study was conducted from July, 2010- June, 2011 in Zoonoses Research Laboratory of Ethiopian Health and Nutrition Research Institute. During this study period a total of 200 brain tissue samples were collected from animals head submitted for routine rabies diagnosis. All the brain tissue samples were tested for rabies using Direct, Rapid Immunohistochemical Test, and Direct Fluorescence Antibody Test. Results: Above two-thirds (67.5%, 135 of 200) of the animal brain tissues examined using direct, Rapid Immunohistochemistry Test were found positive for rabies antigen that showed 100% sensitivity and specificity of direct, Rapid Immunohistochemistry Test compared to the results obtained by Direct Fluorescent Antibody test. Conclusion: The direct, Rapid Immunohistochemistry Test showed equivalent sensitivity and specificity as compared to Direct Fluorescent Antibody test under laboratory condition. Further study with large sample size and wide range of geographical representation of the country is needed to assess the ease of use and feasibility of this test at regional laboratories and under field conditions.

Rabies in nonhuman primates and potential for transmission to humans: a literature review and examination of selected French national data.

BackgroundThe nonhuman primate (NHP)-related injuries in rabies-enzootic countries is a public health problem of increasing importance. The aims of this work are to collect data concerning rabies transmission from NHPs to humans; to collate medical practices regarding rabies postexposure prophylaxis (PEP) in different countries, and to provide an evidence base to support the decision to apply rabies PEP in this context.MethodologyTo retrieve information, we conducted a literature search from 1960 to January 2013. All reports of rabies in NHPs and rabies transmission to humans by infected NHPs were included. Also included were studies of travelers seeking care for rabies PEP in various settings.Data collected by the French National Reference Centre for Rabies concerning NHPs submitted for rabies diagnosis in France and human rabies exposure to NHPs in travelers returning to France were analyzed for the periods 1999–2012 and 1994–2011, respectively.Principal findingsA total of 159 reports of rabies in NHPs have been retrieved from various sources in South America, Africa, and Asia, including 13 cases in animals imported to Europe and the US. 134 were laboratory confirmed cases. 25 cases of human rabies following NHP-related injuries were reported, including 20 from Brazil. Among more than 2000 international travelers from various settings, the proportion of injuries related to NHP exposures was about 31%. NHPs rank second, following dogs in most studies and first in studies conducted in travelers returning from Southeast Asia. In France, 15.6% of 1606 travelers seeking PEP for exposure to any animal were injured by monkeys.Conclusions/significanceAlthough less frequently reported in published literature than human rabies, confirmed rabies cases in NHPs occur. The occurrence of documented transmission of rabies from NHPs to human suggests that rabies PEP is indicated in patients injured by NHPs in rabies-enzootic countries.

Enhanced passive bat rabies surveillance in indigenous bat species from Germany--a retrospective study.

In Germany, rabies in bats is a notifiable zoonotic disease, which is caused by European bat lyssaviruses type 1 and 2 (EBLV-1 and 2), and the recently discovered new lyssavirus species Bokeloh bat lyssavirus (BBLV). As the understanding of bat rabies in insectivorous bat species is limited, in addition to routine bat rabies diagnosis, an enhanced passive surveillance study, i.e. the retrospective investigation of dead bats that had not been tested for rabies, was initiated in 1998 to study the distribution, abundance and epidemiology of lyssavirus infections in bats from Germany. A total number of 5478 individuals representing 21 bat species within two families were included in this study. The Noctule bat (Nyctalus noctula) and the Common pipistrelle (Pipistrellus pipistrellus) represented the most specimens submitted. Of all investigated bats, 1.17% tested positive for lyssaviruses using the fluorescent antibody test (FAT). The vast majority of positive cases was identified as EBLV-1, predominately associated with the Serotine bat (Eptesicus serotinus). However, rabies cases in other species, i.e. Nathusius' pipistrelle bat (Pipistrellus nathusii), P. pipistrellus and Brown long-eared bat (Plecotus auritus) were also characterized as EBLV-1. In contrast, EBLV-2 was isolated from three Daubenton's bats (Myotis daubentonii). These three cases contribute significantly to the understanding of EBLV-2 infections in Germany as only one case had been reported prior to this study. This enhanced passive surveillance indicated that besides known reservoir species, further bat species are affected by lyssavirus infections. Given the increasing diversity of lyssaviruses and bats as reservoir host species worldwide, lyssavirus positive specimens, i.e. both bat and virus need to be confirmed by molecular techniques.

Antigen detection of rabies virus in brain smear using direct Rapid Immunohistochemistry Test

Rabies is zoonotic disease caused by a fatal, neurotropic virus. Rabies virus is classified into the Genus of Lyssavirus under the yang family of Rhabdoviridae . Rabies affecting hot- blooded animals, as well as human. Dogs, cats, monkeys are the vectors or reservoirs for rabies and the virus was transmitted through the saliva after infected animal’s bites. The aim of this study was to conduct rapid diagnosis to detect rabies viral antigen in brain smear using immunohistochemical (IHC) method namely direct Rapid Immunohistochemical Test (dRIT). A total number of 119 brain samples were achieved from Bukittinggi Veterinary Laboratory, West Sumatra. Standardisation and validation of the method were compared to Fluorescent Antibody Test (FAT) as a golden standard for rabies diagnosis. Results show that dRIT was a very good method, it can be performed within two hours without the need of fluorescent microscope. The samples were tested using FAT and from 119 samples tested, 80 (67.23%) samples were positive for rabies and 39 (32.77%) samples were negative for rabies whereas using dRIT showed that 78 (65.54%) samples were positive for rabies and 41 (34.45%) samples were negative for rabies. The dRIT results were validated by comparing them with FAT results as a golden standard for rabies. The relative sensitivity of dRIT to FAT was 97.5% and the relative specificity to FAT was 100% (with Kappa value of 0.976, stated as excellent). The achievement showed that dRIT is very potential diagnostic tool and is highly recommended to be used widely as a rapid diagnosis tool for rabies. Key Words: Rabies, Antigen Detection, Immunohistochemistry, Direct Rapid Immunohistochemical Test (dRIT)

Hospital Records (2006-2013) of Dogbite Cases and Laboratory Confirmation of Dog Rabies in Niger State, Nigeria

The hospital records of dog bite cases reported to the government hospitals across Niger State between January, 2006 and July, 2013 were investigated. Additionally, records of animal samples submitted to the National Veterinary Research Institute (NVRI), Vom-Nigeria for confirmatory rabies diagnosis during same period were investigated. Data on dog bite victims including year/month of bite, sex of victims, age and sites of bite were retrieved and analyzed using descriptive statistics. Results indicated that a total of 223 cases were recorded with the highest number (40 cases) recorded in 2012 and the least (10 cases) recorded in 2013. Higher proportions of victims (66.8%) were males and 46.2% of victims were children below the age of 15 years. Majority (81.3%) of bite was inflicted on the legs and then to some extent (14.3%) on the hands. A total of 1976 animal samples were submitted to NVRI, Vom for rabies diagnosis during the reporting period with 55.6% being confirmed positive but none was submitted from Niger State. Considering that over 81% of bite sites occurred on the legs, it suggests a possible prolong incubation period of rabies in victims. This may enhance misdiagnosis of rabies due to none or poor follow up of dog bite victims in our society. Similarly, non-submission of animal samples to NVRI, Vom from Niger State for rabies diagnosis suggest non-surveillance of rabies in the state. Enhanced surveillance of animal and human rabies in the state and Nigeria at large is highly recommended.

Molecular double-check strategy for the identification and characterization of European Lyssaviruses

The “gold standard” for post-mortem rabies diagnosis is the direct fluorescent antibody test (FAT). However, in the case of ante-mortem non-neural sample material or decomposed tissues, the FAT reaches its limit, and the use of molecular techniques can be advantageous. In this study, we developed and validated a reverse transcription PCR cascade protocol feasible for the classification of samples, even those for which there is no epidemiological background knowledge. This study emphasises on the most relevant European lyssaviruses.In a first step, two independent N- and L-gene based pan-lyssavirus intercalating dye assays are performed in a double-check application to increase the method's diagnostic safety. For the second step, characterization of the lyssavirus positive samples via two independent multiplex PCR-systems was performed. Both assays were probe-based, species-specific multiplex PCR-systems for Rabies virus, European bat lyssavirus type 1 and 2 as well as Bokeloh bat lyssavirus. All assays were validated successfully with a comprehensive panel of lyssavirus positive samples, as well as negative material from various host species.This double-check strategy allows for both safe and sensitive screening, detection and characterization of all lyssavirus species of humans and animals, as well as the rapid identification of currently unknown lyssaviruses in bats in Europe.

Sensitivity comparison of immunofluorescent techniques for detection of rabies virus antigen from brain specimens

The fluorescent antibody test (FAT) is most preferred method to visualize fine particles of rabies viral antigen in rabies infected tissues. In present study, formalin-fixed brain tissues from 100 clinically rabid animals were heat treated and tested for the presence of rabies virus antigen by direct immunofluorescent (IF) staining. The results were compared with those obtained from direct IF staining of acetone- fixed smears. The evaluation of rabies status between fresh and formalin – fixed tissue was in agreement in 100% of the cases. These results suggested that this technique is a valid procedure for routine diagnosis of rabies, particularly in situations in which fresh tissue is not available.

Stray dog trade fuelled by dog meat consumption as a risk factor for rabies infection in Calabar, southern Nigeria.

Rabies is a preventable zoonosis with the highest case fatality of any disease in the world. In the developing world, it is transmitted mainly by dog bites. In parts of southern Nigeria, dog meat is a delicacy. To highlight trade in stray dogs as a major risk factor for rabies in animals and humans in south-south Nigeria. Patients admitted into the University of Calabar Teaching Hospital (UCTH) with a diagnosis of rabies between July and October 2012 were analysed for risk factors, post exposure prophylaxis (PEP), health seeking behaviour and outcome. Focused group interview were also conducted among traders/handlers of stray dogs. Ten cases of rabies in subjects aged 3 to 52 years were recorded in these five months period. Eight of the cases were male and apparently got infected directly or indirectly through the trade in stray dogs for human consumption. None had proper PEP and all patients died. Stray dog trade, fuelled by eating of dog meat, is a risk factor for human and animal rabies in Calabar, southern Nigeria. Culling of stray dogs, control of stray dogs' trade and public enlightenment on PEP is recommended.

Rural Rabies Prevention Project - A ‘One Health’ Experiment in India: An Overview

Aim: To assess the feasibility of implementing approach to prevent human rabies and control animal rabies in a rural community. Study Design: Health research in a rural setting. Place and Duration of Study: A medical college and a veterinary college along with an animal welfare organization delivered a wide array of integrated services in three villages' i.e. Kumbalagodu, Thagachikuppe and Gerupalya near Bangalore, India comprising a population of 10,220 persons for a period of two years from December, 2009 to November, 2011. The nearby three villages of Ramohally, Vinayakanagara and Bhimanakuppe with a population of 6,023 persons formed the control group, with no project inputs. Methodology: This consisted of household surveys at the beginning and end of two years ; rabies awareness campaigns; clinical and laboratory surveillance of rabies in dogs; rabies post-exposure prophylaxis (PEP) in humans; pre-exposure rabies prophylaxis (PrEP) by intradermal route in school children, pet dog owners and veterinarians ; mass dog vaccination and deworming; and sero-surveillance in both dogs and humans. Results: The ratio of veterinary and medical manpower in study villages was 1: 11 and dog to human ratio was 1: 23.The information, education and communication materials developed and used were domestic outdoor wall writings (11), domestic indoor annual wall calendar (2000), school book labels (1000); game charts (16); wall posters (65); flip chart (15); rabies educational DVD (1). There were 102 local cable television transmissions on rabies prevention. 69 persons received rabies PEP. PrEP was given to 368 school children, pet dog owners and veterinarians. Sixty one human serum samples were analyzed by rapid fluorescent focus inhibition test for rabies antibody detection. Sixteen veterinarians were trained to use direct rapid immunohistochemical test (dRIT) for rabies diagnosis. Six ruminants were confirmed rabid by dRIT. There were no cases of human rabies. The cost of entire project was US $ 85,958. Conclusion: A blend of medical, veterinary and animal welfare were successfully delivered through a health approach. Based on this success a conceptual model was evolved to propagate its replication in other rural communities across India.

Diagnosis of rabies from brain: Comparison of histochemical and histopathological approaches

Accurate laboratory diagnosis of rabies can impact significantly on the reduction of rabies related deaths every year. Receiving fresh samples for authentic diagnosis in a laboratory is practically unfeasible in tropical countries and working with fresh brain samples renders increased chances of infection therefore, formalin fixed tissue samples offer better promise as a practically feasible approach for diagnostic investigation. Thus, present study was envisaged to compare the effectiveness of immunohistochemistry (IHC) and histopathology in comparison to gold standard fluorescent antibody test (FAT) in diagnosis of rabies from brain samples of 34 rabies suspected animals (13 dogs, 11 buffaloes, 8 cattle, 1 cat and 1 horse). Sensitivity and accuracy of histopathological demonstration of Negri bodies was found to be 83.33% and 88.88%. Sensitivity and accuracy of IHC in rabies diagnosis was found to be 100%, exhibiting good agreement to FAT. IHC provides a promising alternative approach to gold standard FAT where FAT is not feasible and it should always be preferred method of choice over histopathology technique.

Comparison of Hair Follicle and Skin for Ante Mortem Detection of Rabies: A Molecular Approach

Background : Rabies is an enzootic, fatal disease and early detection of this disease is necessary. Till now a reliable diagnosis is possible only after death of animal. Objectives : So the present study was undertaken to use the molecular approaches like nested RTPCR and SYBR Green real time PCR for early diagnosis of rabies in suspected animals using less invasive non neural tissues like skin biopsy and hair follicles. Method : 12 cases of rabies suspected live animals were presented to the Veterinary Clinics, GADVASU, Ludhiana, India. Results : The sensitivity of nested RT-PCR for hair follicles and skin samples was 50% and 57.1% respectively. A sensitivity of 62.5% and 71.4% was observed with real time PCR in hair follicles and skin samples. Conclusion : We suggest that non-invasive molecular approaches may be used for the early and accurate diagnosis of rabies in animals.

Antemortem diagnosis of rabies from skin by TaqMan real time PCR

Present study revealed application of TaqMan real time PCR technique for diagnosis of rabies viral RNA from 11/20 antemortem skin samples with a sensitivity of 92.85%. The successful use of TaqMan real time PCR concluded that it was a viable, alternative tool for the antemortem diagnosis of rabies. Results correlated well with those of the post-mortem fluorescent antibody test performed on brain specimens of same animals.

Public Health Investigation in a Military Camp After Diagnosis of Rabies in a Dog—Afghanistan, 2012: Table 1

Rabies is one of the risks to which travelers are exposed when going abroad. During the summer of 2012, a rabid dog died in an International Military Transit Camp in Afghanistan, leading to a public health investigation briefly reported here. The lessons learned from this episode are that such investigations are complex and that information for travelers needs to be improved.

Evaluation of Real-Time RT-PCR Assay for Routine Laboratory Diagnosis of Classical Rabies in Post-Mortem Brain Samples from Naturally Infected Different Species of Animals

Evaluation of Real-Time RT-PCR Assay for Routine Laboratory Diagnosis of Classical Rabies in Post-Mortem Brain Samples from Naturally Infected Different Species of Animals

Deteksi Virus Rabies Pada Kasus Ante-Mortem Dengan RT-PCR

Rabies virus detection using Reverse Transcriptase Polymerase Chain Reaction (RT – PCR) was considered to have high sensitivity and specificity. This method is relatively faster and easy to perform in comparison with other methods such as Fluorescent Antibody Test (FAT) and Mouse Inoculation Test (MIT). Therefore, the RT PCR method is used as ante mortem diagnosis of rabies. A total of 74 specimens such as saliva, conjuctival swabs and under tongue swabs were collected from the bites of animal transmitting rabies cases. The 74 specimens were collected from 28 human cases of suspected rabies outbreaks in 2009-2013 that has been tested in the Virology Laboratory, Center for Biomedical and Basic Technology of Health. All specimens examined by RT - PCR method using two primer pairs that amplify the partial gene regions of the N and G genes of the rabies virus. Two of the 74 specimens gave positive results of rabies by RT - PCR, i.e saliva and under-tongue swab from human cases of animal bites in 2009. RT-PCR assay can be used for ante mortem diagnosis of the rabies virus. The laboratory results are influenced by the type of specimen and collection time.

Molecular Detection of Rabies from Milk

Background : Outward spread of rabies virus from the CNS leads to infection of almost all organs and have been reported in various secretions and excretions viz. saliva, urine, CSF, tears (corneal smear). Although transmission of rabies virus from consuming unpasteurized milk from an infected animal is theoretically possible, no human or animal has ever been reported to develop rabies via this route. Neither there had been any practical proof of making claim about shedding of rabies virus in milk. This work aimed to identify the presence of rabies virus in unpasteurized raw milk from naturally-infected animals that were confirmed positive for rabies by FAT on brain tissue. Method : Out of total 25 animals showing clinical signs of rabies, milk sample was obtained from 17 lactating animals. Brief history was recorded and an attempt was made by employing advanced molecular approach TaqMan real time PCR on milk samples with an aim to detect the presence of rabies viral RNA. Confirmatory diagnosis of rabies was made by applying immunofluorescence techniques on brain tissue after death of an animal. Results : The present finding depicts the presence of rabies viral RNA in 4/17(23.52%) milk sample with a sensitivity of 60% when compared with FAT applied on brain tissue. Conclusion : A complete perusal of literature revealed that there had not been a single reported study to detect the presence of rabies viral RNA in milk samples. Although with this study it is now proved practically that rabies viral RNA can be found in milk samples from lactating animals however the infectivity of unpasteurized raw milk needs to be evaluated.

台湾における狂犬病の疫学と我が国における診断能力向上の取り組み

台湾における狂犬病の疫学と我が国における診断能力向上の取り組み

Evaluation of Rapid Diagnostic Tests for Rabies Diagnosis in Nigeria

Evaluation of Rapid Diagnostic Tests for Rabies Diagnosis in Nigeria