A step forward in molecular diagnostics of lyssaviruses--results of a ring trial among European laboratories.

Rabies is a lethal and notifiable zoonotic disease for which diagnostics have to meet the highest standards. In recent years, an evolution was especially seen in molecular diagnostics with a wide variety of different detection methods published. Therefore, a first international ring trial specifically designed on the use of reverse transcription polymerase chain reaction (RT-PCR) for detection of lyssavirus genomic RNA was organized. The trial focussed on assessment and comparison of the performance of conventional and real-time assays. In total, 16 European laboratories participated. All participants were asked to investigate a panel of defined lyssavirus RNAs, consisting of Rabies virus (RABV) and European bat lyssavirus 1 and 2 (EBLV-1 and -2) RNA samples, with systems available in their laboratory. The ring trial allowed the important conclusion that conventional RT-PCR assays were really robust assays tested with a high concordance between different laboratories and assays. The real-time RT-PCR system by Wakeley et al. (2005) in combination with an intercalating dye, and the combined version by Hoffmann and co-workers (2010) showed good sensitivity for the detection of all RABV samples included in this test panel. Furthermore, all used EBLV-specific assays, real-time RT-PCRs as well as conventional RT-PCR systems, were shown to be suitable for a reliable detection of EBLVs. It has to be mentioned that differences were seen in the performance between both the individual RT-PCR systems and the laboratories. Laboratories which used more than one molecular assay for testing the sample panel always concluded a correct sample result. Due to the markedly high genetic diversity of lyssaviruses, the application of different assays in diagnostics is needed to achieve a maximum of diagnostic accuracy. To improve the knowledge about the diagnostic performance proficiency testing at an international level is recommended before using lyssavirus molecular diagnostics e.g. for confirmatory testing.

Oral vaccination of foxes against rabies in Turkey between 2008 and 2010.

Following a sustained spill-over event from dogs to foxes, fox rabies spread rapidly in the Aegean region, Turkey. In order to control the outbreak a program of oral vaccination of foxes against rabies was introduced. In the selected vaccination area three annual campaigns between 2008 and 2010 were undertaken during the winter months whereby the vaccine baits were distributed exclusively by plane using a density of 18 baits per km2. Subsequently, fox rabies cases were reported only from locations bordering the non-vaccinated areas. Hence, it was shown that fox rabies control by means of oral rabies vaccination is feasible in Turkey. However, for the progress towards the elimination of fox-mediated rabies in Turkey to be maintained, it is necessary that political and financial support is secured to extend oral vaccination where infected foxes remain.

Report of the first meeting of the middle East and eastern europe rabies expert bureau, istanbul, Turkey (june 8-9, 2010).

Rabies is a threat in all parts of the world where animal reservoirs persists, including Eastern Europe and the Middle East. Rabies experts from seven Middle East and Eastern European countries (Croatia, Egypt, Georgia, Iran, Serbia, Turkey, and Ukraine) met for two days in Istanbul, Turkey (June 8-9, 2010), to exchange information on the epidemiological situation concerning human and animal rabies in their respective countries and to discuss strategies for rabies elimination and control. They decided to establish a regional network, the Middle East and Eastern Europe Rabies Expert Bureau (MEEREB), a regional network of experts, to increase collaboration in rabies prevention and control at the local, regional, and global levels.

[A human rabies case with antemortem diagnosis]. / Yasarken tani konulan bir insan kuduz olgusu.

Rabies, which is an acute, progressive, fatal zoonotic infectious disease, is almost always caused by the bite of rabid animals containing rabies virus in their saliva. Since there is no established specific therapy for rabies, preventive and prophylactic measures are of critical importance. In this report a case of human rabies diagnosed antemortem, was presented. A 29 year old man was admitted to Harran University Hospital (in Sanliurfa province, located at southeastern Anatolia) emergency service with symptoms of high fever, general weakness, paresthesia of the right arm, hypersalivation and dysphagia. The patient with poor socioeconomical status was living in a rural area and his anamnesis revealed a history of dog bite about five months ago. It was learned that he refused vaccination against rabies after the bite event, despite the warnings of his relatives. Shortly after admission, the patient's neurological status severly deteriorated; he became increasingly agitated. Upon the development of progressive respiratory failure, the patient underwent ventilatory support and heavily sedated with presumptive diagnosis of rabies. A nuchal skin biopsy, cerebrospinal fluid, saliva and corneal smear were sent to the Ministry of Agriculture and Rural Affairs Etlik Central Veterinary Control and Research Institute Rabies Diagnosis Laboratory in Ankara. The corneal smear was positive for rabies virus antigen revealed by direct fluorescent antibody test and saliva sample was also positive for rabies virus RNA by reverse-transcriptase polymerase chain reaction assay. Thus, on the third day of the admission the diagnosis was confirmed and on day 11, the patient was deceased due to rabies encephalitis. This case report emphasizes the importance of public education particularly in low socio-economic and socio-cultural areas, about rabies transmission and preventive and prophylactic measures that should be taken after animal bite.

Rabies in foxes, Aegean region, Turkey.

At the end of the 1990s in the Aegean region of Turkey, rabies rapidly spread among foxes. This spread likely resulted from spillover infection from dogs and led to increased rabies cases among cattle. To control this outbreak, oral rabies vaccination of foxes has been used.

Identification of novel canine rabies virus clades in the Middle East and North Africa.

Four novel phylogenetic clades of canine rabies virus (RABV) variants have been identified in the Middle East and North Africa. The three novel Middle Eastern clades comprise RABV isolates from the borders between Israel and neighbouring countries. The North African clade (Africa 4) comprises four RABV isolates from Egypt and one from Israel. We characterized various RABV lineages antigenically by using a panel of monoclonal antibodies to the nucleoprotein (N) and phylogenetically by analysis of entire N gene sequences. The estimated mean substitution rate for the N gene alignment (2.7x10(-4) substitutions per site per year) is comparable with previous estimates for RABV. The application of a molecular clock indicates the emergence of current canine RABV diversity to have occurred at about the same time (approx. 1870) in the Middle East and Europe, following divergence from established lineages in Africa and Asia.

Rabies emergence among foxes in Turkey.

Sixteen rabies isolates recently collected from mainland Turkey and two isolates held within a British archive were used to form a representative cohort from a range of vectors, and were analyzed to identify potential causes for an increase of rabies within the fox (Vulpes vulpes) population in Turkey. Each isolate was characterized by sequence analysis of the nucleoprotein gene and compared phylogenetically to the cohort, to isolates from neighboring countries and to isolates from continental Europe and Russia. From this analysis the isolates could be divided into three groups associated with geographic location. This included a western group, an eastern group, and one isolate that did not group with any other Turkish isolate. This observation was also found using the heteroduplex mobility assay as an alternative method for typing rabies virus isolates. Further comparison with isolates from neighboring countries suggests that this isolate was related to viruses present in Georgia and could represent a recent import to Turkey from that country. Within the two larger groups, sequence data were obtained from both infected dogs and foxes suggesting that there has been transmission of virus between these two species. The direction of transmission could not be identified by the phylogenetic analysis, although absence of rabies within the fox population in previous years suggests that this could represent a recent spillover from the domestic dog to the fox.