Prevalence of pathogens in ticks feeding on humans. Tinne Lernout

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1 Prevalence of pathogens in ticks feeding on humans Tinne Lernout

2 Contexte Available data for Belgium: localized geographically questing ticks or feeding ticks on animals collection at one moment in time or short period

3 Methods

be: Short questionnaire (data on geographical location of bite and circumstances) generation

4 Methods Collection of ticks attached to humans by citizens Period 1 st April 31 st October 2017 Through website Tekennet.be/TiquesNet.be: Short questionnaire (data on geographical location of bite and circumstances) generation of personal code Tick attached on piece of paper with transparent tape + code Sent by postal mail to Coda-Cerva. No stamp Ticks stored at -20 C

5 Press release 30/03/2017

6 Identification of species and stage Stage: size / number of legs / genital aperture Gender: size of scutum / genital aperture Species: length of mouthparts, scutum (shape/color/pattern), colour, RIVM Photo M. Madder

7 DNA extraction At Coda-Cerva (current Sciensano) Homogenisation of individual nymph and adult ticks in MEM using a tissue lyser (3min, 25Hz) and a 5mm metal bead; larvae pooled by month of tick bite DNA extraction from the homogenate using the MagMAX total nucleic acid Isolation kit and the MagMAX Express-24 purification system (Life Technologies) Contact: nick.deregge@sciensano.be

8 Analysis of pathogens At RIVM in the Netherlands (Hein Sprong) Multiplex PCR for Borrelia burgdorferi sensu lato (s.l.), Anaplasma spp., Borrelia miyamotoi, Candidatus Neoehrlichia mikurensis, Rickettsia spp. and Babesia spp. Methods (PCR, qpcr and sequencing) are described in Jahfari S. et al. PLoS Negl Trop Dis Oct 5;10(10)

9 Results

10 Collection of ticks

12 Species : 99% Ixodes ricinus Ixodes ricinus Ixodes hexagonus Larva Nymphe Adult Adult Dermacentor reticulatis

13 % I. ricinus I. hexagonus D. reticulatis Larva 5.2% Nymph 76.6% Adult female 15.6% Adult male 2.6% Total Number of ticks Nymph Aprl May June July Aug Sep Oct Number of ticks analysed by species and by month Daniel M et al. Parasit Vectors Sep 18;8:478

14 Prevalence Borrelia burgdorferi s.l. Nb of ticks % positives 95%CI Brussels Flanders Wallonia Total Species: B. afzelii (52%), B. garinii (21%), B. spielmani (7%), B. burgdorferi s.s. (5%), B. bavariensis (1%), B. Valaisiana (14% - pathogenicity?) Overall mean prevalence of Borrelia infection in ticks in Europe: 13.7% (range: 0 49) Rizzoli A. et al. Euro Surveill. 2011;16(27):pii=19906

15 By province % positive ticks for Bb sl Antwerp Limburg Vlaams Br Oost Vl West Vl Br Wallon Liège Lux Namur Hainaut N=348 N=238 N=200 N=60 N=35 N=169 N=143 N=122 N=107 N=73

16 Other tick-borne diseases Human cases in Belgium (per year) Brussels (n=20) Flanders (n=881) Wallonia (n=614) Total (n=1515) % pos questing ticks % pos feeding ticks animals Anaplasma phagocytophilum 1 conf 20 probable % ( ) 1.5% ( ) 1.8% ( ) % % Borrelia miyamotoi None 5% ( ) 2.5% ( ) 2.1% ( ) 2.4% ( ) % - Candidatus Neoehrlichia mikurensis None 0 3% ( ) 2.8% ( ) 2.8% ( ) 0.4% - Babesia spp. None 0 1.4% ( ) 1.6% ( ) 1.5% ( ) % 1.3% Rickettsia spp imported cases 5% ( ) 7.6% ( ) 5.7% ( ) 6.8% ( ) %

17 Human cases in Belgium (per year) Brussels (n=20) Flanders (n=881) Wallonia (n=614) Total (n=1515) % pos questing ticks % pos feeding ticks animals Anaplasma phagocytophilum 1 conf 20 probable % ( ) 1.5% ( ) 1.8% ( ) % % Borrelia miyamotoi None 5% ( ) 2.5% ( ) 2.1% ( ) 2.4% ( ) % - Candidatus Neoehrlichia mikurensis None 0 3% ( ) 2.8% ( ) 2.8% ( ) 0.4% - Babesia spp. None 0 1.4% ( ) 1.6% ( ) 1.5% ( ) % 1.3% Rickettsia spp imported cases 5% ( ) 7.6% ( ) 5.7% ( ) 6.8% ( ) %

18 Subspecies Babesia B. venatorum (77.3%) B. divergens (13.6%) B. microti (9.1%) Rickettsia Ixodes ricinus: all R. helvetica R. raoultii : in 2/5 dermacentor ticks

19 Larvae 0/7 pools larvae positive for B. burgdorferi s.l. 1/7 pools larvae positive for B. miyamotoi 4/7 pools larvae positive for R. helvetica

20 Co-infections 4% of nymphs and adult ticks carried 2 pathogens and 4 ticks were infected with 3 pathogens Overview of pathogen combinations

21 Future Data can be used in addition to other factors for risk maps for Lyme borreliosis Screening for other pathogens (TBEV, francisella tularensis?) A new study in 3-4 years will allow to follow-up evolution

22 Conclusions Lyme borreliosis can be contracted all over the country. But no panic, 86% ticks borrelia-free Prevalence in all regions below 20% antibiotic prophylaxis not recommended (BAPCOC) Presence of other tick-borne pathogens (although low prevalence), with aspecific clinical symptoms important to raise awareness Prevention of tick bites: or BAPCOC:

23 References OTBD Claerebout et al. Parasit Vectors. 2013;6:183 Cochez et al. Zoonoses Public Health Aug;62(5):331-3a De Keukeleire et al. Vector Borne Zoonotic Dis Feb;17(2): Heylen et al. Environ Microbiol Mar;18(3): Lempereur et al. Parasitol Res Apr;110(4): Lempereur et al. Clin Microbiol Infect Jan;21(1):96.e1-7

Acknowledgements All the citizens who collected the ticks My colleagues from Sciensano: Katrien Tersago, Laurence Geebelen and David Jaminé for their help in identification of ticks & Nick de Regge

24 Acknowledgements All the citizens who collected the ticks My colleagues from Sciensano: Katrien Tersago, Laurence Geebelen and David Jaminé for their help in identification of ticks & Nick de Regge and Célia Thoraval for DNA extraction Hein Sprong and Manoj Fonville from RIVM in the Netherlands for the PCR analyses The study was financed by the Flemish Agentschap Zorg en Gezondheid and by the Walloon Agence pour une Vie de Qualité

The Essentials of Ticks and Tick-borne Diseases

The Essentials of Ticks and Tick-borne Diseases Presenter: Bobbi S. Pritt, M.D., M.Sc. Director, Clinical Parasitology Laboratory Co-Director, Vector-borne Diseases Laboratory Services Vice Chair of Education