zard) and two live birds (one goshawk and one buzzard) found in the ASL of Nuoro, were transferred to Bonassai from the wildlife rehabilitation center of Olbia.
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Abstracts / International Journal of Infectious Diseases 53S (2016) 4–163
overwintering of these viruses, or the emergence of more virulent strains of these viruses. Methods & Materials: To explore this problem in the subtropics (northwest Florida) we measured seroconversion to 3 endemic EHD viruses as well and BTV in a sentinel herd using well established serological methods. We also monitored the herd using a novel RT-qPCR assay for detection of all known EHDV serotypes. Simultaneously, we trapped Culicoides using CDC miniature light traps and by aspiration directly off of white-tailed deer enclosed within a 500 acre preserve. Results: From January to March seroconversion to EHDV-1 and 6 occurred across the herd in all age groups of animals. The virus was transiently detected by molecular methods in hosts during this time period. Compared to midge abundance and diversity in the previous season (July-December), few species were present and none of established vectors were trapped in any trap or aspirated directly off of deer. Conclusion: Transmission of these viruses appears to be yearround, even in the absence of “known” vectors. The ability of alternative vector species to transmit HD, besides those known to transmit these viruses in North America (C. sonorensis, C. variipennis and C. insignis), warrants further investigation. http://dx.doi.org/10.1016/j.ijid.2016.11.165 19.100 Genetic disease susceptibility and surveillance system sensitivity: Classical scrapie K. Schulman ∗ , T. Lyytikäinen Finnish Food Safety Authority Evira, Risk Assessment Research Unit, Helsinki/FI Purpose: Susceptibility of sheep to classical scrapie (CS) is modulated by the PrP gene and can be grouped into five NSP Types, NSPI being most resistant and NSPV most susceptible. Surveillance is targeted on fallen stock (FS), i.e. dead or culled over 18-month-old animals. Testing of animals slaughtered for human consumption (SHC) is limited. Our aim was to assess the effect of genetic susceptibility on the surveillance system sensitivity (SSe) in Finland in 2008-2014. The SSe is the probability that at least one infected animal is detected if the population is infected at or above the design prevalence (P*). Methods & Materials: We estimated the SSe by scenario tree modelling. Nodes and input parameters are described in Table 1. To account for variability and uncertainty, we fitted distributions to key parameters. Table 1 Nodes and input parameters for the model. Node
Branches
Explanation
NSP Type
NSPI-V
NSP Type distribution of sheep in Finland based on breed PrP genotypes and breed distribution
Death type
SHC, FS
True SHC and FS population proportions
Infected
yes, no
Effective probability of infection (EPI) = adjusted riska (AR) x (P*)b
Sampled
yes, no
Actual sampling numbers
Test result
pos, neg
Actual test results
a AR is based on the estimated risk ratio (RR) of different NSP Types against the average risk in SHC in Great Britain (GB) (Arnold and Ortiz-Pelaez 2014) and adjusted for the NSP Type distribution in Finland. b P*= 0.1% based on the OIE Terrestrial Animal Health Code.
Results: Cases in GB were concentrated to FS giving high RR’s in FS and susceptible NSP Types. When adjusted for Finland, the AR was highest for NSPV in FS. The SSe for Finland showed very little fluctuation in 2008-2014. Even at its lowest point in 2010, the mean was 99.72%. The representative SSe for the same year, i.e. without considering NSP Types and the added sensitivity in focusing the surveillance on FS, was 60.80%. Conclusion: The Finnish sheep population is relatively sensitive to CS. Consideration of NSP Types increases the accuracy of the SSe. Genetic susceptibility factors can be of great value when developing/assessing surveillance. http://dx.doi.org/10.1016/j.ijid.2016.11.166 19.101 Suspected case of West Nile Virus (WNV) in the territory of ASL Sassari (Sardinia) F. Sgarangella a,∗ , D. Marongiu b , G. Bitti b , S. Masala b , V. Floris b , B. Mossa b , P. Desini b a
Azienda Sanitaria Locale, Servizio di Sanità Animale, Sassari, ITALY/IT b Azienda Sanitaria Locale, Servizio di Sanità Animale, Sassari/IT Purpose: The purpose of this paper is to illustrate the health management of a suspect case of West Nile in the territory of ASL Sassari. Methods & Materials: In Sardinia, eight wildlife rehabilitation centers transfer animals with serious illnesss to two centers of regional recovery (CRAS): Bonassai in Sassari and Monastir in Cagliari. On April 4, 2015, three dead birds (two goshawks and one buzzard) and two live birds (one goshawk and one buzzard) found in the ASL of Nuoro, were transferred to Bonassai from the wildlife rehabilitation center of Olbia. Both dead birds tested WNV-positive (RT-PCR). The National Reference Center for the Study of Exotic Diseases in Teramo confirmed the positive diagnosis of lineage 2 on September 21, 2015. The two live birds tested positive with a serum neutralization test. Although from September, 4, 2015 to September 21, 2015 the two birds were not kept in isolation, biosecurity procedures were performed adhering to standard protocols typical for seropositive birds, as dictated by current legislation. The Local Crisis Unit decided to take two control samples, separated by 15 days, including blood, serum, and cloacal swabs of other birds introduced in the CRAS. They also set up two cages for catching insect vectors. Meanwhile hospitals, blood transfustions, and primary care providers were alerted in order to protect human health. Results: Two buzzards of 25 sampled birds were positive by serum neutralization (Title 1:20 and 1:10), with no increase in their antibody titers. No birds or captured insects were WNV-positive when tested. Conclusion: The two dead birds who were WNV-positive, had not stayed at the CRAS in Bonassai. The two live birds, though positive serologically, were not considered suspects by current legislation. It is possible, however, that in the period between the introduction of the animals and the control, the virus could had circulated. As a precaution, the serologically positive birds were treated as suspects, as evident by the activation of the described procedures. In the described case, a new procedure was adopted that involves the isolation of all incoming birds that come to the CRAS, pending the laboratory results for WND. http://dx.doi.org/10.1016/j.ijid.2016.11.167
