Rabies control in KwaZulu-Natal, South Africa.

PROBLEM: Urbanization, large dog populations and failed control efforts have contributed to continuing endemicity of dog-mediated rabies in KwaZulu-Natal province, South Africa. APPROACH: From 2007 to 2014 we used a OneHealth approach to rabies prevention, involving both the human and animal health sectors. We implemented mass vaccination campaigns for dogs to control canine rabies, and strategies to improve rabies awareness and access to postexposure prophylaxis for people exposed to rabies. LOCAL SETTING: A rabies-endemic region, KwaZulu-Natal is one of the smallest and most populous South African provinces (estimated population 10 900 000). Canine rabies has persisted since its introduction in 1976, causing an average of 9.2 human rabies cases per annum in KwaZulu-Natal from 1976 to 2007, when the project started. RELEVANT CHANGES: Between 2007 and 2014, the numbers of dog vaccinations rose from 358 611 to 395 000 and human vaccines purchased increased form 100 046 to 156 996. Strategic dog vaccination successfully reduced rabies transmission within dog populations, reducing canine rabies cases from 473 in 2007 to 37 in 2014. Actions taken to reduce the incidence of canine rabies, increase public awareness of rabies and improve delivery of postexposure prophylaxis contributed to reaching zero human rabies cases in KwaZulu-Natal in 2014. LESSONS LEARNT: Starting small and scaling up enabled us to build strategies that fitted various local settings and to successfully apply a OneHealth approach. Important to the success of the project were employing competent, motivated staff, and providing resources, training and support for field workers.

Towards canine rabies elimination: Economic comparisons of three project sites.

An appreciation of the costs of implementing canine rabies control in different settings is important for those planning new or expanded interventions. Here we compare the costs of three canine rabies control projects in South Africa, the Philippines and Tanzania to identify factors that influence the overall costs of rabies control efforts. There was considerable variation in the cost of vaccinating each dog, but across the sites these were lower where population density was higher, and later in the projects when dog vaccination coverage was increased. Transportation costs comprised a much higher proportion of total costs in rural areas and where house-to-house vaccination campaigns were necessary. The association between the cost of providing PEP and human population density was less clear. The presence of a pre-existing national rabies management programme had a marked effect on keeping infrastructure and equipment costs for the project low. Finally, the proportion of the total costs of the project provided by the external donor was found to be low for the projects in the Philippines and South Africa, but likely covered close to the complete costs of the project in Tanzania. The detailed economic evaluation of three recent large-scale rabies control pilot projects provides the opportunity to examine economic costs across these different settings and to identify factors influencing rabies control costs that could be applied to future projects.

The role of non-governmental organisations in controlling rabies: the Global Alliance for Rabies Control, Partners for Rabies Prevention and the Blueprint for Rabies Prevention and Control.

Rabies control worldwide has been inadequate and neglected for many decades, and the disease continues to predominantly affect poor communities in Africa and Asia. As a zoonosis for which the main reservoir and vector, the domestic dog (Canis familiaris), is an economically non-viable species, the absence of cross-sectoral cooperation has been a major factor in the lack of effective control efforts. A shift in global focus is required to concentrate on the fact that rabies has the highest case fatality ratio of all infectious human diseases and that it still affects human health more significantly than many other infectious diseases that are perceived to pose more significant risks. Equally necessary is an acknowledgement that rabies control is complex and that the task of creating and executing a strategic plan for the disease can be overwhelming for those governments in the developing world where dog rabies is most problematic. Nonprofit organisations operate independently of governments and intergovernmental organisations and can play a dynamic role in inter-sectoral collaboration and the creation of approaches and strategies for the control of complex diseases such as rabies. In 2008, the Global Alliance for Rabies Control (GARC) established Partners for Rabies Prevention (PRP), a widely representative group of rabies stakeholders and experts, which endeavours to support public-private rabies control activities throughout the world. After a landscape analysis, the PRP proceeded to develop and launch the Blueprint for Rabies Prevention and Control (comprising the Blueprint for Canine Rabies Prevention and Control; the Blueprint for Fox Rabies Prevention and Control and the Rabies Surveillance Blueprint). Subsequently, the Stepwise Approach towards Rabies Elimination (SARE) was embedded into the Canine Rabies Blueprint. The SARE is a planning and self-assessment tool that countries can use to develop activities and monitor progress towards a national programme and strategy for sustainable rabies control and elimination. Each of the elements needed to execute the SARE-derived strategy is cross-linked to the Canine Rabies Blueprint, which provides the specific methods and tools required, supported by references and examples. Together, the Canine Rabies Blueprint and the SARE should be regarded as a novel and dynamic operational toolkit, and a resource that provides comprehensive information for the development and implementation of rabies control strategies, built entirely on the principles of 'One Health'.

Cela fait des dizaines d'années que la rage est une maladie négligée et que les efforts consacrés à la combattre à l'échelle mondiale sont insuffisants ; la maladie continue donc à sévir en plusieurs endroits de la planète en affectant surtout les communautés pauvres d'Afrique et d'Asie. La rage est une zoonose dont le principal réservoir et vecteur, le chien domestique (Canis familiaris), est une espèce ne présentant pas d'enjeu économique de sorte que c'est surtout l'absence de coopération intersectorielle qui est la principale cause du manque d'efficacité des activités de lutte. Il faut faire évoluer ces efforts à l'échelle mondiale à partir du constat que la rage est de toutes les maladies infectieuses humaines celle qui a le taux de létalité le plus élevé et que son impact sur la santé humaine reste supérieur à celui d'autres maladies infectieuses pourtant perçues comme présentant des risques plus significatifs. Il est tout aussi indispensable de prendre conscience du fait que la lutte contre la rage est une entreprise complexe et que la conception et l'exécution d'un plan stratégique contre cette maladie constituent des tâches écrasantes pour les gouvernements des pays en développement, où la rage canine pose le plus de problèmes. Les organisations à but non lucratif opérant indépendamment des gouvernements et des organisations intergouvernementales peuvent jouer un rôle pour dynamiser la collaboration intersectorielle et contribuer à la conception d'approches et de stratégies de lutte contre des maladies complexes telles que la rage. En 2008, l'Alliance mondiale contre la rage (GARC) a lancé l'initiative Partners for Rabies Prevention (PRP), un groupe formé d'un vaste éventail de parties prenantes et d'experts dans le domaine de la rage et ayant pour vocation de soutenir les activités relevant de partenariats public-privé pour lutter contre la rage partout dans le monde. Après une analyse globale de la situation, le partenariat a élaboré et mis en route le Plan directeur de prévention et de contrôle de la rage (doté de trois volets, à savoir les Plans directeurs pour la prévention et le contrôle de la rage canine et vulpine et le Plan directeur pour la surveillance de la rage). Par la suite, l'Approche raisonnée de l'élimination de la rage (SARE) a été intégrée au Plan directeur pour la prévention de la rage canine. SARE est un outil de planification et d'auto-évaluation mis à disposition des pays afin de les aider à concevoir leurs activités et à suivre les progrès enregistrés dans l'élaboration de leurs stratégies et programmes nationaux de lutte et d'élimination de la rage. Chaque élément opérationnel des stratégies élaborées sur la base de SARE est rattaché au Plan directeur pour la prévention et le contrôle de la rage canine, qui fournit les méthodes et les outils spécifiques nécessaires ainsi que des références et des exemples pertinents. Pris ensemble, le Plan directeur et SARE sont à envisager à la fois comme une boîte à outils opérationnelle innovante et dynamique et comme une base d'informations exhaustives pour l'élaboration et la mise en oeuvre de stratégies de lutte contre la rage, entièrement conçues dans une perspective « Une seule santé ¼.

La lucha antirrábica a escala mundial lleva muchos decenios de inadaptación y de relegación a un segundo plano, mientras la enfermedad sigue afectando principalmente a las comunidades pobres de África y Asia. Tratándose de una zoonosis cuyo principal reservorio y vector, el perro doméstico (Canis familiaris), es una especie económicamente inviable, la falta de cooperación intersectorial es uno de los principales factores que explican la ausencia de medidas de control eficaces. Es imperativo imprimir un giro a las líneas de trabajo mundiales para empezar a tener en cuenta que la rabia presenta la tasa de letalidad más alta de todas las enfermedades infecciosas del ser humano y que sigue afectando a la salud humana en mayor medida que otras muchas infecciones consideradas en cambio más peligrosas. También hay que tomar conciencia de que la lucha contra la rabia es compleja y de que los gobiernos de los países en desarrollo, donde la rabia es más problemática, a veces se ven superados por la titánica empresa de elaborar y aplicar un plan estratégico en la materia. Las organizaciones sin ánimo de lucro, que trabajan independientemente de gobiernos y organizaciones intergubernamentales, pueden cumplir una función dinámica de cara a la colaboración intersectorial y la creación de métodos y procedimientos de lucha contra enfermedades complejas como la rabia. Así, en 2008, la Alianza Mundial de Lucha contra la Rabia (GARC) estableció «Partners for Rabies Prevention¼ (PRP), amplio grupo representativo de los círculos de especialistas y otros interlocutores relacionados con la rabia que se dedica a respaldar en todo el mundo actividades de lucha antirrábica que federan a los sectores público y privado. Tras un análisis de la situación general, PRP procedió a elaborar y poner en práctica el «Plan maestro [Blueprint] de prevención y control de la rabia¼ (que a su vez se declina en un plan maestro de prevención y control de la rabia canina; un plan maestro de prevención y control de la rabia vulpina; y un plan maestro de vigilancia antirrábica). Ulteriormente, al plan maestro contra la rabia canina se le incorporó el «método progresivo para la eliminación de la rabia¼ (SARE, por sus siglas en inglés). El SARE es una herramienta de planificación y autoevaluación que los países pueden emplear para definir actividades y seguir de cerca la progresión hacia un programa y una estrategia nacionales de control y eliminación sostenibles de la rabia. Cada uno de los elementos necesarios para ejecutar la estrategia que se deriva del SARE guarda vínculos cruzados con el plan maestro contra la rabia canina, en el que se facilitan los métodos e instrumentos específicos necesarios, acompañados de referencias y ejemplos. El plan maestro contra la rabia canina y el SARE deben ser vistos conjuntamente como una novedosa y dinámica «caja de herramientas prácticas¼ y una fuente de información completa para definir y aplicar estrategias de lucha antirrábica, asentadas ambas por entero en los principios de «Una sola salud¼.

The SARE tool for rabies control: Current experience in Ethiopia.

The Stepwise Approach towards Rabies Elimination (SARE) tool was developed through a joint effort of the Food and Agriculture Organization (FAO) of the United Nations and the Global Alliance for Rabies Control (GARC), to provide a standard mechanism for countries to assess their rabies situation and measure progress in eliminating the disease. Because the African continent has the highest per capita death rate from rabies, and Ethiopia is estimated to have the second largest number of rabies deaths of all African countries, Ethiopia undertook a self-assessment by means of the Stepwise Approach towards Rabies Elimination (SARE) tool. In February 2016, the Ethiopian government hosted an intersectoral consultative meeting in an effort to assess the progress that has been made towards the control and elimination of canine rabies. The SARE assessment identified a number of critical gaps, including poor inter-sectoral collaboration and limited availability and access to dog vaccine, while the existence of a surveillance system for rabies and legislation for outbreak declaration and response were among the strengths identified. The SARE tool enabled key criteria to be prioritized, thereby accelerating the National Strategy and ensuring that Ethiopia will progress rapidly in line with the goals set by the global community for the elimination of human rabies deaths by 2030. Although the analysis showed that Ethiopia is still in the early stages of rabies control (Stage 0.5/5), the country shows great promise in terms of developing a SARE-guided National Rabies Prevention and Control Strategy.

Towards Canine Rabies Elimination in KwaZulu-Natal, South Africa: Assessment of Health Economic Data.

Rabies remains a significant problem throughout much of the developing world. An estimated 69 000 people die annually from exposure to rabies. Most of these deaths are the result of being bitten by a rabid dog. Mass vaccination campaigns targeting dogs have been implemented around the world in an attempt to control or eliminate canine rabies. We analysed the vaccination and cost data for a campaign in the KwaZulu-Natal province of South Africa; we found that the cost per dog vaccinated to be $6.61 for mass campaigns and $5.41 for local campaigns. We also estimated the cost of human post-exposure prophylaxis (PEP). The cost of PEP is approximately $64.50 on average per patient, and $333 on average for the 9% of patients who receive RIG. We also found that the districts that vaccinated the most dogs per capita experienced the highest rates of human treatment and thus had the highest PEP costs.

The Pan-African Rabies Control Network (PARACON): A unified approach to eliminating canine rabies in Africa.

Even though Africa has the highest per capita death rate from rabies of any continent, and the disease is almost entirely transmitted by the bites of rabid dogs, there has been no coordinated pan-African approach to controlling canine rabies. In order to attain an inclusive and unified network, the Pan-African Rabies Control Network (PARACON) was established in 2014. By following the 'One Health' concept, which involves close coordination between animal and human health sectors across national, regional and continental levels, PARACON will provide a platform to facilitate and promote coordinated and sustainable control strategies and programmes. Meetings will take place at regular intervals and will be centred on the involvement by key focal persons from the medical and veterinary sectors. The inaugural meeting was held in South Africa in June, 2015 and was focused around interactive discussions and workshops, whilst updating country representatives on the tools available to aid them in developing and implementing sustainable rabies intervention strategies. Experts from various global organizations, institutions and industry participated in the discussions and shared their experience and expertise. The workshops focused on the latest format of the Rabies Blueprint platform (www.rabiesblueprint.com), which in the broadest sense assists with control and elimination campaigns, including educational and advocacy drives, improvement of surveillance and diagnosis and the systematic monitoring of progress. Together with the Stepwise Approach towards Rabies Elimination, the Blueprint is a planning tool to help countries free themselves from canine-transmitted rabies.

Human cases of Sindbis fever in South Africa, 2006-2010.

Sindbis virus (SINV), the prototype positive-sense RNA alphavirus, causes febrile arthritis and is present throughout Afro-Eurasia. Little is known of the epidemiology of Sindbis fever due to insufficient surveillance in most endemic countries. The epidemiological features of Sindbis fever in humans in South Africa are described here based on a retrospective study of suspected arbovirus cases submitted for laboratory investigation from 2006 to 2010. Cases were detected annually mostly during the late summer/early autumn months and an increase in cases was noted for 2010, coinciding with an outbreak of Rift Valley fever. Cases were reported most often from the central plateau of South Africa and involved mostly males. No severe or fatal cases were reported and cases were associated with febrile arthralgia as commonly reported for SINV infection. Further surveillance is required to reveal the true extent of the morbidity of Sindbis fever in South Africa.

Dog rabies in southern Africa: regional surveillance and phylogeographical analyses are an important component of control and elimination strategies.

In the resource-poor settings where dog rabies remains endemic, the demonstration of a need to divert scarce funds towards exhaustive surveillance activities is no easy task. Here, we investigate a recent case of human rabies in South Africa, which generated much public interest and wide media coverage. One of the factors contributing to the hype was an uncertainty about the geographical origin of the infection. This provided an opportunity to highlight the importance of increased regional surveillance and basic phylogeographical analyses in rabies control and elimination strategies. Our aim was to elucidate the origins of the virus responsible for this case, as the patient was from a well-vaccinated area that had been free from dog rabies cases for many years. The phylogeographical techniques that we applied would also be most useful in any end-stage infectious disease control programme, specifically in verifying the source of novel cases in order to rapidly respond towards maintaining the integrity of disease-free areas. The most likely origin of our case was shown to be from outside the disease-free area and indeed from outside the country of South Africa. We conclude that phylogeographical techniques can provide rapid and statistically rigorous answers to epidemiologically pertinent questions that impact on disease control strategies and resource allocation, but this will require coordinated regional surveillance practices.

High prevalence of antibodies against canine adenovirus (CAV) type 2 in domestic dog populations in South Africa precludes the use of CAV-based recombinant rabies vaccines.

Rabies in dogs can be controlled through mass vaccination. Oral vaccination of domestic dogs would be useful in the developing world, where greater vaccination coverage is needed especially in inaccessible areas or places with large numbers of free-roaming dogs. From this perspective, recent research has focused on development of new recombinant vaccines that can be administered orally in a bait to be used as adjunct for parenteral vaccination. One such candidate, a recombinant canine adenovirus type 2 vaccine expressing the rabies virus glycoprotein (CAV2-RG), is considered a promising option for dogs, given host specificity and safety. To assess the potential use of this vaccine in domestic dog populations, we investigated the prevalence of antibodies against canine adenovirus type 2 in South African dogs. Blood was collected from 241 dogs from the Gauteng and KwaZulu-Natal provinces. Sampled dogs had not previously been vaccinated against canine adenovirus type 1 (CAV1) or canine adenovirus type 2 (CAV2). Animals from both provinces had a high percentage of seropositivity (45% and 62%), suggesting that CAV2 circulates extensively among domestic dog populations in South Africa. Given this finding, we evaluated the effect of pre-existing CAV-specific antibodies on the efficacy of the CAV2-RG vaccine delivered via the oral route in dogs. Purpose-bred Beagle dogs, which received prior vaccination against canine parvovirus, canine distemper virus and CAV, were immunized by oral administration of CAV2-RG. After rabies virus (RABV) infection all animals, except one vaccinated dog, developed rabies. This study demonstrated that pre-existing antibodies against CAV, such as naturally occurs in South African dogs, inhibits the development of neutralizing antibodies against RABV when immunized with a CAV-based rabies recombinant vaccine.

A case study of rabies diagnosis from formalin-fixed brain material.

Rabies is caused by several Lyssavirus species, a group of negative sense RNA viruses. Although rabies is preventable, it is often neglected particularly in developing countries in the face of many competing public and veterinary health priorities. Epidemiological information based on laboratory-based surveillance data is critical to adequately strategise control and prevention plans. In this regard the fluorescent antibody test for rabies virus antigen in brain tissues is still considered the basic requirement for laboratory confirmation of animal cases. Occasionally brain tissues from suspected rabid animals are still submitted in formalin, although this has been discouraged for a number of years. Immunohistochemical testing or a modified fluorescent antibody technique can be performed on such samples. However, this method is cumbersome and cannot distinguish between different Lyssavirus species. Owing to RNA degradation in formalin-fixed tissues, conventional RT-PCR methodologies have also been proven to be unreliable. This report is concerned with a rabies case in a domestic dog from an area in South Africa where rabies is not common. Typing of the virus involved was therefore important, but the only available sample was submitted as a formalin-fixed specimen. A real-time RT-PCR method was therefore applied and it was possible to confirm rabies and obtain phylogenetic information that indicated a close relationship between this virus and the canid rabies virus variants from another province (KwaZulu-Natal) in South Africa.

Evolutionary history of African mongoose rabies.

Two biotypes or variants of rabies virus (RABV) occur in southern Africa. These variants are respectively adapted to hosts belonging to the Canidae family (the canid variant) and hosts belonging to the Herpestidae family (the mongoose variant). Due to the distinct host adaptation and differences in epidemiology and pathogenesis, it has been hypothesized that the two variants were introduced into Africa at different times. The objective of this study was to investigate the molecular phylogeny of representative RABV isolates of the mongoose variant towards a better understanding of the origins of this group. The study was based on an analysis of the full nucleoprotein and glycoprotein gene sequences of a panel of 27 viruses. Phylogenetic analysis of this dataset confirmed extended evolutionary adaptation of isolates in specific geographic areas. The evolutionary dynamics of this virus variant was investigated using Bayesian methodology, allowing for rate variation among viral lineages. Molecular clock analysis estimated the age of the African mongoose RABV to be approximately 200 years old, which is in concurrence with literature describing rabies in mongooses since the early 1800 s.

Soybean blotchy mosaic virus, a New Cytorhabdovirus Found in South Africa.

A previously unidentified plant Rhabdovirus sp. associated with a blotchy mosaic symptom of soybean (Glycine max), prevalent in the lower-lying, warmer soybean production areas of South Africa, was isolated and partially characterized. The virus was shown to be transmitted by mechanical inoculation and at least one species of leafhopper (Peragallia caboverdensis Lindberg (Cicadellidae, Agalliinae)). To determine the morphology and virion size, as well as intercellular accumulation, negative-stained preparations or embedded ultrathin sections of infected plant samples were observed under a transmission electron microscope. The distribution of the virions within the cytoplasm and its bullet-shaped morphology and size (338 to 371 nm by 93 nm) suggested that it is a putative member of the genus Cytorhabdovirus. Degenerate primers designed to a conserved region of the polymerase gene of a number of Rhabdovirus spp. were used in reverse-transcriptase polymerase chain reaction with total RNA from symptomatic plants as template. Amplicons were sequenced and compared with related sequences available on GenBank. The analysis confirmed that the virus was related to Cytorhabdovirus spp., with the highest nucleotide similarity being 60.7% with Northern cereal mosaic virus. The particle morphology, typical virion accumulation in the cytoplasm of infected cells, nucleotide sequence similarity with that of other plant Rhabdovirus spp., and unique symptoms on soybean suggest that the virus is a previously unknown Cytorhabdovirus sp., for which we propose the name Soybean blotchy mosaic virus (SbBMV).

Lagos bat virus virulence in mice inoculated by the peripheral route.

Lagos bat virus (LBV) constitutes genotype (gt) 2 in the Lyssavirus genus. In contrast to the gt1 lyssavirus, rabies virus (RABV), LBV was reported to have markedly reduced levels of peripheral pathogenicity. However, this opinion was based on a study of one isolate of LBV only and the reduction in pathogenicity was essentially attributed to the amino-acid substitution at position 333 of glycoprotein ectodomain. In the present study we have demonstrated that peripheral pathogenicity of representatives of LBV in a murine model is as high as that of RABV. Comparison of amino-acid substitutions among the viral glycoproteins, demonstrated significant differences within two antigenic sites between different phylogenetic lineages of LBV. Such molecular variability potentially contributes to differences in peripheral pathogenicity of lyssaviruses.

Development and evaluation of a real-time reverse transcription-loop-mediated isothermal amplification assay for rapid detection of Rift Valley fever virus in clinical specimens.

This paper reports on the development and validation of a real-time reverse transcription-loop-mediated isothermal amplification assay (RT-LAMP) targeting the genomic large RNA segment of Rift Valley fever virus (RVFV). The set of six designed RT-LAMP primers identified strains of RVFV isolated in geographically distinct areas over a period of 50 years; there was no cross-reactivity with other genetically related and unrelated arboviruses. When testing serial sera and plasma from sheep experimentally infected with wild-type RVFV, there was 100% agreement between results of the RT-LAMP, a TaqMan-based real-time PCR, and virus isolation. Similarly, the assay had very high levels of diagnostic sensitivity and specificity when testing various clinical specimens from humans and animals naturally infected with the virus during recent outbreaks of the disease in Africa. The detection of specific viral genome targets in positive clinical specimens was achieved in less than 30 min. As a highly accurate, rapid, and very simple nucleic acid detection format, the RT-LAMP has the potential to be used in less-well-equipped laboratories in Africa and as a portable device during RVF outbreaks in remote areas, and it can be a valuable tool for the differential diagnosis of viral hemorrhagic fevers.

Molecular epidemiology of rabies: focus on domestic dogs (Canis familiaris) and black-backed jackals (Canis mesomelas) from northern South Africa.

Phylogenetic relationships of rabies viruses recovered from black-backed jackals (Canis mesomelas) and domestic dogs (Canis familiaris) in northern South Africa were investigated to determine whether the black-backed jackal is an emerging maintenance host species for rabies in this region. A panel of 123 rabies viruses obtained from the two host species between 1980 and 2006 were characterised by nucleotide sequencing of the cytoplasmic domain of the glycoprotein gene and the non-coding G-L intergenic region. Through phylogenetic analysis a viral cluster specific to black-backed jackals and spanning a 5-year period was delineated in western Limpopo. Virus strains associated with domestic dogs prevail in densely populated communal areas in north-eastern Limpopo and in south and eastern Mpumalanga. The data presented in this study indicated the likelihood that black-backed jackals are capable of sustaining rabies cycles independent of domestic dogs. It is proposed that wildlife rabies control strategies, in synergy with domestic animal vaccination should be considered for effective control of rabies in South Africa.

Evaluation of a rapid immunodiagnostic test kit for detection of African lyssaviruses from brain material.

A rapid immunodiagnostic test kit was evaluated against a selection of isolates of lyssavirus genotypes occurring in Africa. The test was carried out in parallel comparison with the fluorescent antibody test (FAT) and isolates representing previously established phylogenetic groups from each genotype were included. The specificity of the rapid immunodiagnostic test compared favourably with the FAT and was found to detect all representatives of genotypes 1, 2, 3 and 4 in brain samples of either field cases or suckling mouse brain inoculates.

Can rabies be eradicated?

Rabies, an acute progressive encephalitis, is an ancient zoonosis. Its distribution encompasses all continents, except Antarctica. Agents consist of at least 11 species orgenotypes of rhabdoviruses, in the Genus Lyssavirus. Susceptible natural hosts include all mammals. Primary reservoirs reside in the Orders Carnivora and Chiroptera. A plethora of variants, maintained by a diversity of abundant hosts, presents a challenge to a strict concept of true eradication. Globally, the domestic dog remains the most significant species for viral transmission, responsible for millions of suspect human exposures and tens of thousands of fatalities. As such, this single major target provides an ideal opportunity for focused intervention programmes in humane disease prevention and control, driven by laboratory-based surveillance and guided via modern epidemiological insights. Historically, substantial technical progress throughout the 20th century led to the development of safe, affordable and efficacious animal and human vaccines, resulting in declining disease burdens in selected developed and developing countries. Regional and local disease resurgence occurs, due in part to a combination of political and economic instability, environmental perturbations, and shifting government priorities. Society must recall that despite the recent recognition of other important emerging infectious diseases, none exceed the case fatality rate of rabies. Given the clear relevance of rabies in public health, agriculture, and conservation biology, substantive international progress must continue towards enhanced public awareness, human rabies prevention, wildlife rabies control, and canine rabies elimination, with renewed collaborative vigour.

Epidemiology and pathogenicity of African bat lyssaviruses.

Lyssaviruses belonging to all four known African Lyssavirus genotypes (gts) have been reported and isolated from SouthAfrica over the past few decades. These are: (1) Duvenhage virus (gt4), isolated again in 2006 from a human fatality; (2) Mokola virus (gt3), isolated irregularly, mostly from cats; (3) Lagos bat virus (gt2) continually isolated over the past four years from Epomophorus fruit bats and from incidental terrestrial animals and (4) Rabies virus (gt1) - with two virus biotypes endemic in mongoose and in canid species (mostly domestic dogs, jackals and bat-eared foxes), respectively. Only two of these are associated with bats in Southern Africa, viz. Duvenhage virus and Lagos bat virus (gts 4 and 2). For both these genotypes the authors have embarked on a programme of comparative study of molecular epidemiology. Duvenhage virus nucleoprotein nucleotide sequence analysis indicated a very low nucleotide diversity even though isolates were isolated decades apart. In contrast, individual isolates of Lagos bat virus were found to differ significantly with respectto nucleoprotein gene nucleotide sequence diversity as well as in pathogenicity profiles.

Phylogeny of Lagos bat virus: challenges for lyssavirus taxonomy.

Lagos bat virus (LBV) belongs to genotype 2 of the Lyssavirus genus. The complete nucleoprotein (N), phosphoprotein (P), matrixprotein (M) and glycoprotein (G) genes of 13 LBV isolates were sequenced and phylogenetically compared with other lyssavirus representatives. The results identified three different lineages of LBV. One of these lineages demonstrated sufficient sequence diversity to be considered a new lyssavirus genotype (Dakar bat lyssavirus). The suggested quantitative separation of lyssavirus genotypes using the N, P, M and G genes was also investigated using P-distances matrixes. Results indicated that the current criteria should be revised since overlaps between intergenotypic and intragenotypic variation occur.

Transmission of Activated-Episomal Banana streak OL (badna)virus (BSOLV) to cv. Williams Banana (Musa sp.) by Three Mealybug Species.

Four different mealybug species (Dysmicoccus brevipes, Planococcus citri, P. ficus, and Pseudococcus longispinus) were evaluated for their ability to transmit putative activated-episomal Banana streak OL (badna)virus (BSOLV) to banana cv. Williams (Cavendish subgroup, AAA). Expressible endogenous sequences of banana streak viruses (BSVs) have been reported to be present in the DNA of various Musa hybrids, including FHIA-21 (AAAB). To obtain activated episomal BSOLV for this experimental transmission study, intentional stress by tissue culture propagation was applied to indexed FHIA-21 which, while free of other viruses, can contain activated episomal BSOLV. Immunocapture polymerase chain reaction and triple-antibody sandwich enzyme-linked immunosorbent assay results revealed that 13.4% of the derived progeny of the mother plants were infected with episomal BSOLV. Four of these BSOLV-infected progeny were used as sources of episomal virus for transmission studies. D. brevipes, Planococcus citri, and P. ficus mealybugs were able to transmit the putative activated episomal BSOLV. Control plants for the transmission experiments included FHIA-21 corms with no background history of tissue culture, as well as virus-free Williams plants. Episomal Banana streak GF (badna)virus (BSGFV) was transmitted from asymptomatic corm-derived FHIA-21 plants by P. citri and P. ficus. This is the first report of P. ficus as a vector of BSVs.