Summary Crimean‐Congo haemorrhagic fever virus (CCHFV) is one of the most widespread of all medically important arboviruses with ticks of the Hyalomma spp. serving as the main vectors. Infection of livestock by CCHFV serves as a route of exposure to humans, as a reservoir of disease and as a route of importation. This study discusses the pathways and data requirements for a qualitative risk assessment for the emergence of CCHFV in livestock in Europe. A risk map approach is proposed based on layers that include the potential routes of release (e.g. by migrating birds carrying infected ticks) together with the main components for exposure, namely the distributions of the tick vectors, the small vertebrate host reservoirs and the livestock. A layer on landscape fragmentation serves as a surrogate for proximity of livestock to the tick cycle. Although the impact of climate change on the emergence of CCHF is not clear, comparing the distribution of risk factors in each layer currently with those predicted in the 2080s with climate change can be used to speculate how potential high‐risk areas may shift. According to the risk pathway, transstadial and/or transovarial transmission in the tick vector are crucial for CCHFV spread. Vector competence and tick vector switching, however, remain critical factors for CCHFV colonization of new regions in Europe. The species of migratory bird is also an important consideration in the release assessment with greater abundance and biodiversity of ground‐dwelling birds in southern Europe than in northern Europe.

A Polymerase Chain Reaction (PCR) and Southern blot hybridization for the detection of Theileria annulata are described. The PCR used primers amplifying a 785 base-pair fragment of the T. annulata gene which encodes the 30 kDa major merozoite surface antigen, Tams1. The sensitivity of the PCR in bovine blood was 1 piroplasm in 1 microl of blood. T. buffeli, T. parva, Babesia bigemina, B. bovis and B. divergens were not detected. The PCR detected down to 1 infected acinus/tick in resting and partially fed adult Hyalomma anatolicum anatolicum ticks and was negative for T. lestoquardi and T. equi, which are transmitted by this tick but are not infective to cattle. The specificity of the PCR was checked using 30 stocks of T. annulata, all of which were detected. Three stocks of T. lestoquardi, 4 of T. equi and 1 each of T. buffeli, T. parva, B. bigemina, B. bovis and B. divergens were used to ascertain there were no cross-reactions. A nested PCR using separate primers for the first reaction and the same primers for the second reaction detected T. annulata to the same sensitivity and specificity in saponin-extracted DNA samples stored for long periods at -20 degrees C.

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BackgroundSpotted fever group (SFG) rickettsiae have recently been identified for the first time in UK ticks. This included the findings of Rickettsia helvetica in Ixodes ricinus and Rickettsia raoultii in Dermacentor reticulatus. This paper further investigates the occurrence of SFG rickettsiae in additional geographically distinct populations of D. reticulatus, and for the first time, investigates the occurrence of SFG rickettsiae in UK populations of Haemaphysalis punctata ticks.MethodsQuesting D. reticulatus and H. punctata were collected at a number of sites in England and Wales. DNA from questing ticks was extracted by alkaline lysis and detection of rickettsiae DNA was performed, in addition to detection of A. phagocytophilum, N. mikurensis, C. burnetii and B. burgdorferi sensu lato.ResultsThis paper builds on previous findings to include the detection of spotted fever Rickettsia which showed the highest homology to Rickettsia massiliae in Haemaphysalis punctata, as well as R. helvetica in D. reticulatus. The occurrence of SFG rickettsiae in D. reticulatus in the UK appears to be confined only to Welsh and Essex populations, with no evidence so far from Devon. Similarly, the occurrence of SFG rickettsiae in H. punctata appears confined to one of two farms known to be infested with this tick in North Kent, with no evidence so far from the Sussex populations. Anaplasma phagocytophilum, Neoehrlichia mikurensis, Coxiella burnetii and Borrelia burgdorferi sensu lato DNA was not detected in any of the ticks.ConclusionThese two tick species are highly restricted in their distribution in England and Wales, but where they do occur they can be abundant. Following detection of these SFG rickettsiae in additional UK tick species, as well as I. ricinus, research should now be directed towards clarifying firstly the geographic distribution of SFG rickettsiae in UK ticks, and secondly to assess the prevalence rates in ticks, wild and domesticated animals and humans to identify the drivers for disease transmission and their public health significance.

Crimean-Congo haemorrhagic fever virus (CCHFV) is a zoonotic virus transmitted by Hyalomma ticks, the immature stages of which may be carried by migratory birds. In this study, a total of 12 Hyalomma ticks were recovered from five of 228 migratory birds trapped in Spring, 2012 in southern Spain along the East Atlantic flyway. All collected ticks tested negative for CCHFV. While most birds had zero Hyalomma ticks, two individuals had four and five ticks each and the statistical distribution of Hyalomma tick counts per bird is over-dispersed compared to the Poisson distribution, demonstrating the need for intensive sampling studies to avoid underestimating the total number of ticks. Rates of tick exchange on migratory birds during their northwards migration will affect the probability that a Hyalomma tick entering Great Britain is positive for CCHFV. Drawing on published data, evidence is presented that the latitude of a European country affects the probability of entry of Hyalomma ticks on wild birds. Further data on Hyalomma infestation rates and tick exchange rates are required along the East Atlantic flyway to further our understanding of the origin of Hyalomma ticks (i.e., Africa or southern Europe) and hence the probability of entry of CCHFV into GB. Journal of Vector Ecology 41 (1): 128-134. 2016.