Serological testing of Schmallenberg virus in Swedish wild cervids from 2012 to 2016.

BACKGROUND: Schmallenberg virus (SBV) first emerged in Europe in 2011, and in Sweden in late 2012. The virus was still circulating in parts of Europe in 2015. In recent testing, the virus has not been detected in Swedish domestic animals, indicating that it is no longer circulating in Sweden. It is not known if the virus has circulated and is still circulating in Swedish wild cervid populations and whether wildlife can act as virus reservoirs. The aim of this study was to investigate whether SBV has circulated, and is still circulating among wild cervids in Sweden. RESULTS: Ninety-two sera from moose (Alces alces, n = 22), red deer (Cervus elaphus, n = 15), fallow deer (Dama dama, n = 44), and roe deer (Capreolus capreolus, n = 11) were collected and analyzed for antibodies against SBV. The sampling occurred in the southern and middle part of Sweden during three time periods: 1) before the vector season in 2012, 2) after the vector season in 2012, and 3) after the vector season in 2015. Animals from periods 1 and 2 were of varying ages, whereas animals collected in period 3 were born after the vector season 2013. Animals from period 1 (n = 15) and 3 (n = 47) were seronegative, but, 53% (16 of 30) of animals from period 2 were seropositive, determined by SBV competitive ELISA. Samples from period 2 were additionally analyzed for SBV-neutralizing antibodies. Such antibodies were detected in 16/16 SBV-N-antibody-positive, 3/12 negative and 2/2 doubtful sera. The two tests were in accordance at SBV-neutralizing antibody titers of 1:32 or higher. CONCLUSION: Our results show that SBV circulated among wild cervids during the vector season of 2012. Three years later, no SBV-antibodies were detected in animals born after the vector season 2013. The likely absence of SBV circulation in Sweden, in contrast to other parts of Europe, might be explained by the annual occurrence of a vector-free season due to climate conditions. Interpretations are limited by the small sample-size, but the results suggest that the SBV competitive ELISA has high specificity but might have slightly lower sensitivity compared to a seroneutralization assay, when using samples from wild cervids.

Revisiting the phylogeography and demography of European badgers (Meles meles) based on broad sampling, multiple markers and simulations.

Although the phylogeography of European mammals has been extensively investigated since the 1990s, many studies were limited in terms of sampling distribution, the number of molecular markers used and the analytical techniques employed, frequently leading to incomplete postglacial recolonisation scenarios. The broad-scale genetic structure of the European badger (Meles meles) is of interest as it may result from historic restriction to glacial refugia and/or recent anthropogenic impact. However, previous studies were based mostly on samples from western Europe, making it difficult to draw robust conclusions about the location of refugia, patterns of postglacial expansion and recent demography. In the present study, continent-wide sampling and analyses with multiple markers provided evidence for two glacial refugia (Iberia and southeast Europe) that contributed to the genetic variation observed in badgers in Europe today. Approximate Bayesian computation provided support for a colonisation of Scandinavia from both Iberian and southeastern refugia. In the whole of Europe, we observed a decline in genetic diversity with increasing latitude, suggesting that the reduced diversity in the peripheral populations resulted from a postglacial expansion processes. Although MSVAR v.1.3 also provided evidence for recent genetic bottlenecks in some of these peripheral populations, the simulations performed to estimate the method's power to correctly infer the past demography of our empirical populations suggested that the timing and severity of bottlenecks could not be established with certainty. We urge caution against trying to relate demographic declines inferred using MSVAR with particular historic or climatological events.

Investigations and actions taken during 2011 due to the first finding of Echinococcus multilocularis in Sweden.

Echinococcus multilocularis is a parasite that can cause alveolar echinococcosis disease. After the first positive finding of E. multilocularis in Sweden in 2011, a consulting group with representatives from relevant authorities was summoned. In this group, all relevant information was shared, strategies for information dissemination and any actions to be taken due to the finding of E. multilocularis were discussed and decided. The present paper describes the actions taken during 2011 and the results thereof, including surveillance in animals, risk assessment for humans to become infected and recommendations given to the public. Further discussion about whether the parasite was introduced, and if so, how, as well as possible future development of the infection in animals and humans in Sweden and future actions are included.

First detection of Echinococcus multilocularis in Sweden, February to March 2011.

Surveillance for the fox tapeworm, Echinococcus multilocularis, has been carried out in Sweden since 2000, with about 300 red foxes analysed annually. We report the first finding of E. multilocularis in Sweden, in a fox shot in December 2010 in the south-west of the country. A second infected fox shot in the same location was detected in March 2011. This paper describes the national monitoring programme and the ongoing work to estimate the prevalence and spread of the infection.

Surgical implantation of radiotelemetry transmitters in European badgers (Meles meles).

The suitabilities of two subcutaneous and two intraabdominal surgical approaches were evaluated for implantation of telemetry transmitters in the European badger (Meles meles). Two transmitters, one for heart rate and the other for body temperature, were needed in each badger. Five wild badgers were trapped, housed in an outdoor pen, anesthetized, and surgically implanted with one or two transmitters per procedure. A total of 16 transmitters were implanted, 10 subcutaneously and six intraabdominally, and each badger had up to three procedures performed. Six subcutaneous transmitters were placed over the chest wall and four on the dorsal aspect of the neck. Three intraabdominal transmitters were placed free in the abdomen and three were fixed to the abdominal wall. Eight of the subcutaneous transmitters were later damaged or dislodged, probably by mechanical friction, injuries from fighting, or wound licking. The intraabdominal implantation procedures were easier and faster to perform compared with subcutaneous procedures. Two of the free intraabdominal transmitters became thinly encapsulated, with some omental adhesions. The fixed intraabdominal approach for transmitter implantation is preferable in badgers.