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We compiled information on the distribution of ticks in the western Palearctic (11°W, 45°E; 29°N, 71°N), published during 1970-2010. The literature search was filtered by the tick's species name and an unambiguous reference to the point of capture. Records from some curated collections were included. We focused on tick species of importance to human and animal health, in particular: Ixodes ricinus, Dermacentor marginatus, D. reticulatus, Haemaphysalis punctata, H. sulcata, Hyalomma marginatum, Hy. lusitanicum, Rhipicephalus annulatus, R. bursa, and the R. sanguineus group. A few records of other species (I. canisuga, I. hexagonus, Hy. impeltatum, Hy. anatolicum, Hy. excavatum, Hy. scupense) were also included. A total of 10,280 records was included in the data set. Almost 42 % of published references are not adequately referenced (and not included in the data set), host is reported for only 61 % of records and a reference to time of collection is missed for 84 % of published records. Ixodes ricinus accounted for 44.3 % of total records, with H. marginatum and D. marginatus accounting for 7.1 and 8.1 % of records, respectively. The lack of homogeneity of the references and potential pitfalls in the compilation were addressed to create a digital data set of the records of the ticks. We attached to every record a coherent set of quantitative descriptors for the site of reporting, namely gridded interpolated monthly climate and remotely sensed data on vegetation (NDVI). We also attached categorical descriptors of the habitat: a standard classification of land biomes and an ad hoc classification of the target territory from remotely sensed temperature and NDVI data. A descriptive analysis of the data revealed that a principal components reduction of the environmental (temperature and NDVI) variables described the distribution of the species in the target territory. However, categorical descriptors of the habitat were less effective. We stressed the importance of building

The current study reports on a real-time reverse transcription polymerase chain reaction (real-time RT-PCR) ring trial for the detection of Classical swine fever virus (CSFV) genomic RNA undertaken by 10 European laboratories. All laboratories were asked to use their routine in-house real-time RT-PCR protocols and a standardized protocol commonly used by the Friedrich-Loeffler-Institute (FLI) on a panel of well-characterized samples. In general, all participants produced results within the acceptable range. The FLI assay, several in-house assays, and the commercial kits had high analytical sensitivity and specificity values. Nevertheless, some in-house systems had unspecific reactions or suboptimal sensitivity with only a single CSFV genotype. Follow-up actions involved either improvement of suboptimal assays or replacement of specific laboratory assays with the FLI protocol, with or without modifications. In conclusion, the ring trial showed reliability of classical swine fever diagnosis on an international level and helped to optimize CSFV-specific RT-PCR diagnostics. © 2011 American Association of Veterinary Laboratory Diagnosticians.

A real-time polymerase chain reaction (PCR) assay for the rapid detection of African swine fever virus (ASFV), multiplexed for simultaneous detection of swine beta-actin as an endogenous control, has been developed and validated by four National Reference Laboratories of the European Union for African swine fever (ASF) including the European Union Reference Laboratory. Primers and a TaqMan ® probe specific for ASFV were selected from conserved regions of the p72 gene. The limit of detection of the new real-time PCR assay is 5.7-57 copies of the ASFV genome. High accuracy, reproducibility and robustness of the PCR assay (CV ranging from 0.7 to 5.4%) were demonstrated both within and between laboratories using different real-time PCR equipments. The specificity of virus detection was validated using a panel of 44 isolates collected over many years in various geographical locations in Europe, Africa and America, including recent isolates from the Caucasus region, Sardinia, East and West Africa. Compared to the OIE-prescribed conventional and real-time PCR assays, the sensitivity of the new assay with internal control was improved, as demonstrated by testing 281 field samples collected in recent outbreaks and surveillance areas in Europe and Africa (170 samples) together with samples obtained through experimental infections (111 samples). This is particularly evident in the early days following experimental infection and during the course of the disease in pigs sub-clinically infected with strains of low virulence (from 35 up to 70dpi). The specificity of the assay was also confirmed on 150 samples from uninfected pigs and wild boar from ASF-free areas. Measured on the total of 431 tested samples, the positive deviation of the new assay reaches 21% or 26% compared to PCR and real-time PCR methods recommended by OIE. This improved and rigorously validated real-time PCR assay with internal control will provide a rapid, sensitive and reliable molecular tool for ASFV detect

Clinical manifestations of infections by encephalomyocarditis virus (EMCV), belonging to the genus cardiovirus of the family Picomaviridae, emerged in European pig farms in the nineties. Two types of clinical disease were noticed, acute myocarditis, usually in young piglets, and reproductive failure in sows. To understand its relevance in pigs and develop hypotheses on the origin, cause and nature of infection, the occurrence of EMCV infections was studied in domestic pigs in several European countries. In addition, virus spread in pigs and rats as well as risk factors for clinical appearance of EMCV in domestic pig farms were studied to increase our knowledge of the disease and support its prevention and control. Although outbreaks appeared to be clustered in endemic areas, infection usually was restricted to individual farms. The seroprevalence varied considerably among farms, age categories and countries, while sub-clinical infection with EMCV was quite common. The variable clinical picture in pigs in literature was ascribed to the pathogenicity of the EMCV strains, the available infectious dose and/or the susceptibility of the pigs (age, breed). Local rodent populations were often suggested responsible for the observed clustering and re-occurrence in farms. A matched case-control study on risk factors inducing clinical EMCV revealed the presence of mice (OR = 8.3) as a risk factor. The transmission of a myocardial EMC V-strain in fattening piglets was quantified by the basic reproduction ratio (R0) both from experiments (Ro=1.24, 95%-CI = 0.39 - 4.35) and field data (Ro=1.36, 95%-CI 0.93-2.23). Although these results suggested that EMCV transmission among pigs in most cases will be limited (Ro close to 1), both studies remained inconclusive with respect to the threshold value of R0=l. Therefore it could not be concluded whether EMCV could persist in a pig population by pig-to-pig transmission alone (i.e. Ro>l). To estimate the transmission in a compartmentalised

Transmission of encephalomyocarditis-virus ( EMCV) has been estimated in experiments, but never using field data. In this field study, a farm in Belgium was selected where the presence of EMCV was confirmed by necropsy and virus isolation. Serology was used to estimate the transmission parameter R-0. In one compartment with 630 pigs, 6 pens were fully sampled, in the remaining 38 pens, 2 randomly selected pigs were bled. The 151 pigs were bled twice and their serum was tested in a virus neutralisation test. Seroprevalence at the first and second sampling was 41 and 43% respectively, with a cut off value of 1: 40. R-0 was estimated for 2 scenarios, in- and excluding mortality based on the final sizes from the serological results of the second sampling. The R-0 for the fully sampled pens was estimated between 0.6 and 1.7, the combined estimated R-0 of these 6 pens was 1.36 (95%-CI 0.93-2.23). The median of the estimated R-0 of the partially sampled pens was 1.3 and 1.4. Sampling two pigs per pen provided insight into the spread of the virus in the compartment, while the fully sampled pens provided an accurate estimation of R-0. The low R-0 strongly suggests that EMCV is not very effectively transmitted between pigs. The number of seropositive pigs in a pen and the spread in the compartment suggests that other routes of infection are more important, in this case most likely rodents. Preventing viral spread should therefore be focussed on rodent control instead of reduction of contact between pigs.

Due to the probable role played by rodents as a reservoir for the transmission of the EMC virus to pigs, the experiment reported here was performed in order to assess the transmission rate of EMCV within a rat population. Twenty-five eight-week-old Wistar rats housed in individual plastic cages were experimentally infected either with a Greek myocardial EMCV strain (5 rats with a 0.2x10(6) TCID50 dose per rat and 10 rats with a 0.5x104(-5) TCID50 dose per rat, oronasally) or a Belgian myocardial EMCV strain (10 rats with a 0.5x10(4.5) TCID50 dose per rat, oronasally). Two to five days later, each inoculated rat was moved to a new clean cage and coupled with a contact rat to compare the pathogenicity of the two strains and to estimate the basic reproduction ratio R-0, indicating the level of EMCV transmission. During the experiments, faecal virus excretion was measured as well as the serological response against EMCV. After euthanasia, virus isolation was attempted from different rat tissues. Neither strains produced mortality, nor clinical signs and only low titres of neutralising antibodies were found. All contact rats, however, Iwere infected and the virus was isolated from their faeces and from various tissues. Both 10-pair experiments,revealed a point estimate for the R-0 of infinity (95%-CI for both the Greek and Belgian EMCV strains=4.48-infinity), as did the 5-pair experiment with a higher dose of the Greek strain (95%-CI=1.93-infinity). Combining the results front the two 10-pair experiments resulted in an estimate for R-0 of infinity (95%-CI: 9.87-infinity). These results indicate that the EMC virus can spread very easily within a rat population by horizontal rat-to-rat transmission (R(0)much greater than1).

A big epidemic of classical swine fever (CSF) occurred in the European Community in 1997. The first case was reported at the beginning of January 1997 from Germany. The disease presumably spread to the Netherlands, and from there to Italy, Spain and eventually to Belgium. About 30 isolates from these outbreaks were analysed by comparison of the nucleotide sequence data generated from fragments of both the E2 glycoprotein gene (190 nucleotides) and from the 5'-nontranslated region (5'-NTR; 150 nucleotides). By combining epidemiological data with genetic typing, it was found that the outbreaks were related and caused by a virus belonging to the genetic subgroup 2.1. As this type of virus had been reported infrequently in Europe and not at all since 1993, we postulate that it was newly introduced into the European Union (EU). (C) 2000 Elsevier Science B.V.