Tick-Borne Encephalitis Virus, United Kingdom

• Main Authors: Maya Holding, Stuart D. Dowall, Jolyon M. Medlock, Daniel P. Carter, Steven T. Pullan, James Lewis, Richard Vipond, Mara S. Rocchi, Matthew Baylis, Roger Hewson
• Format: Article
• Language: English
• Published: Centers for Disease Control and Prevention 2020-01-01
• Series: Emerging Infectious Diseases
• Subjects: meningitis/encephalitis; viruses; tick-borne encephalitis; tick-borne encephalitis virus; TBEV; louping ill virus
• Online Access: https://wwwnc.cdc.gov/eid/article/26/1/19-1085_article

During February 2018–January 2019, we conducted large-scale surveillance for the presence and prevalence of tick-borne encephalitis virus (TBEV) and louping ill virus (LIV) in sentinel animals and ticks in the United Kingdom. Serum was collected from 1,309 deer culled across England and Scotland. Overall, 4% of samples were ELISA-positive for the TBEV serocomplex. A focus in the Thetford Forest area had the highest proportion (47.7%) of seropositive samples. Ticks collected from culled deer within seropositive regions were tested for viral RNA; 5 of 2,041 ticks tested positive by LIV/TBEV real-time reverse transcription PCR, all from within the Thetford Forest area. From 1 tick, we identified a full-length genomic sequence of TBEV. Thus, using deer as sentinels revealed a potential TBEV focus in the United Kingdom. This detection of TBEV genomic sequence in UK ticks has important public health implications, especially for undiagnosed encephalitis.