VECTOR-SURVEILLANCE IN NORTHERN ITALY

Transcription

1 Stechmücken: Belästigung oder Bedrohung? VECTOR-SURVEILLANCE IN NORTHERN ITALY Gioia Capelli Laboratorio di Parassitologia Istituto Zooprofilattico Sperimentale delle Venezie tel Vienna, 8 giugno 2015

2 WNV in northern Italy since 2008 in north-eastern Italy since 2014 in north-western part too two WNV lineages (lin1 e 2) and several strains the Veneto region is the only area where WNV has been circulating continuously in mosquitoes, animals and humans

3 Objectives of the entomological surveillance 1. knowledge of the species present in the area 2. absolute and relative density 3. pathogens and their rate of infection 4. overwintering 5. introduction of new species of vectors/pathogens 6. WNV: early detection of viral circulation 7. Other benefits: 1. genetic characterization of pathogens

4 WNV entomological surveillance National Plan since 2002 Risk areas after 2008 three areas: ACV, AE and others since 2014 two areas: endemic (province based) and the rest of national territory since 2008 implementation of Regional Plans

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6 WNV the regional plans ER and VEN-FVG ER sistematic trapping every10 km (now 11km) VEN-FVG risk-based

7 ER

8 VEN-FVG

9 WNV the regional plans Piemonte and Lombardia

10 methods Mosquito collection every 15 days Mainly CDC-CO2 traps Pooled mosquitoes (50-200) Molecular viral research gravid trap CO2 trap BG Sentinel

11 An idea of the numbers ,461 mos collected 562,079 pooled for PCR (Calzolari et al., under revision)

12 Ento results 2013 in a map Calzolari et al., in revision

13 dati IZSVe-Regione Veneto and FVG Mosquito infection rate MIR (Veneto) year Rate of infection WNV min-max Pool pos WN1 Pool pos WN ,150-1,418-7

14 Mosquitoes and human infection

15 Not only mosquitoes..

16 Mosquitoes and equines 2013

17 WNV: early detection of viral circulation How predictive is the mosquito positivity?

18 The vector index (Veneto 2012) R=0.843, p< 0.01

19 Can we really prevent human cases?

20 The real problem: blood donors NAT screening from July to November in provinces with a human cases and in those in which human cases of WNND had been reported the previous year But is universal blood screening for West Nile virus cost-effective?

21 Entomologial results vs human and veterinary cases (pos/tested data first recovery WNV) Emilia Romagna (ER) region

22 Entomologial results vs human and veterinary cases (pos/tested data first recovery WNV) VENETO region Anno ( n traps) (43) 2011 (49) 2012 (24) 2013 (54) 2014 (29) MOSQUIT OES 10/2650 (26/07) 2/1621 (26/07) 11/1122 (31/07) 57/3671 (03/07) 7/1291 (08/07) HORSES 98/818 (14/09) 13/737 (24/08) 25/1431 (09/08) 32/2200 (09/08) 25/711 (01/08) 9/1620 (28/08) BIRDS 1/621 (19/02) 0/749 1/617 (30/09) 4/550 (12/09) 1/439 (29/08) 0/199 HUMANS WNND WNF 6 (20/08) 6 (03/09) (27/07) 12 (20/08) (01/09) 38 (18/07) (22/07) 31 (21/07) (24/07) 3 (12/08) (16/08 BLOOD DONORS 2 (29/08) (02/11) 2 (11/09) (12/09) 4 ( /09) 14 (15/07, /08, 04-21/09) 7 ( /08, /09) 1 (09/09)

23 PR OV Province level ER First symptoms WNND Data first human case First symptoms WNF Days in advance mosq pos vs First pool of human cases and donors First donor mosquitoes pos pos WNV WNND BLOOD MO 03/08 14/08 3/08 03/ FE 06/08 13/09 1/09 17/ BO 15/08 24/08 25/08 17/ RE 16/08 // // 17/07 30 // PR 11/09 01/09 // 19/07 54 // RA // // // 24/07 // // PC // // 8/09 13/08 // 26 FC // // // 21/08 // // MO 20/08 // // 23/07 34 // FE // // // 5/08 // // BO 25/08 // // 9/07 47 // RE 27/08 // // 29/07 29 // PR 25/08 // // 4/07 51 // RA // // 3/10 10/09 // 23 PC 1/09 // 2/09 5/

24 PV Province level VENETO First symptoms WNND Data first human case First symptoms WNF First pool of mosquitoes pos WNV Days in advance mosq pos vs human cases and donors First donor pos WNND-WNF BLOOD VE 01/09-22/08 03/ TV 16/08 14/ human only - RO 21/07 24/07 14/09 17/ VR 04/08 04/08 23/08 17/ VI PD 11/08-29/08 - human only - VE TV RO /09 04/08 mos only 35 VR 12/08 16/08-04/ VI /07 mos only - PD

25 VENETO EMILIA-ROMAGNA LOMBARDIA Summary northern Italy 2014 REGIONE / PROVINCE Prima positività entomologica Prima positività ornitologica Data esordio sintomi primo caso WNND Giorni di anticipo della positività entomologica (dt inizio sintomi -data pos entomologica) Giorni di anticipo della positività ornitologica (dt inizio sintomi -data pos ornitologica) Bergamo 15/09/ /08/ Brescia 08/07/ /08/ /09/ Cremona 11/08/ /08/ /08/ Lodi 24/07/ /08/ Milano 02/09/ /09/ Mantova 11/08/ /07/ /09/ Lecco - 22/ Pavia * 02/09/ /08/ Piacenza 11/08/ /09/ /09/ Parma 10/07/ /07/ /08/ Reggio Emilia 05/08/ /07/ /08/ Modena 28/07/ /07/ /08/ Bologna 14/07/ /09/ /08/ Ferrara 11/08/ /08/ Ravenna 16/09/ /09/ Alessandria 27/08/ Venezia Treviso Rovigo 04/08/ Verona 04/08/ /08/ Vicenza 08/07/ Padova

26 The cost of entomological surveillance (north-eastern) The general 2013 estimated costs for the entomological monitoring (66 traps) was 149,687 Entomological surveillance Mosquito collection (S1) Identificationpooling (S2) Viruses detection (S3) Data entry and processing (S4) People employed, position (work/hours) 1 undergraduate (300) 3 scholarship (530) 1 entomologist (60) 1 technician (137) 5 scholarship (642) 1 entomologist (188) 1 biotechnol. (170) 2 scholarship (775) 1 technician (150) 1 technician (780); 1 office worker (100); 1 scholarship (75); 1 biotechnol. (100) 1 entomologist (170); 1 vet (75) Personnel cost (EUR) Reagents, consumables, travel (EUR) Total (EUR)

27 Is the screening of donors necessary? Pupella et al., 2014 Update on West Nile virus in ItalyBlood Transfusion 12(4):

28 Pupella et al., 2014 Update on West Nile virus in Italy Blood Transfusion 12(4): Is the screening of donors necessary?.. most positive donations were whole blood donations, each systematically fractionated into three different blood components (red cells, buffy coats/platelets and plasma). Therefore, by screening donors for WNV, a considerable number of blood recipients were spared exposure to these potentially infectious units. It should be pointed out that the absence of specific anti-wnv protective antibodies in the 11/16 WNV-RNA positive donors made their donations highly infectious. Based on all the above, the 2013 experience with WNV circulation in Italy once again highlights the importance of having rigorous entomological and veterinary surveillance plans in place and of establishing close cooperation among the different players in the health field.

29 The most cost-effective strategy..in 2006 Korves et al. found,..., that universal screening for WNV is not the most appropriate strategy, even in high-infection-short duration transmission areas The most cost-effective strategy in high WNV prevalence areas is seasonal, targeted screening of donations designated for immunocompromised individuals by ID NAT Pupella et al Blood Transfus.; 11(4):

30 Seasonal, targeted screening of donations To use entomological surveillance and veterinary cases as a trigger for starting/stopping the control of human blood units Napoli et al, 2015 BioMed Research International

31 Mean time of notification from mosquito collection Tempi medi di risposta - zanzare Veneto 7,2 gg (range 3-13) Friuli Venezia Giulia 7,2 gg (range 3-13) Emilia-Romagna 6,3 gg (range 1-13) Piemonte 7,3 gg (range 4-17) Lombardia 5,67 gg (range 2-8)

32 In conclusion the entomological screening (integrated with animal and human surveillance) can serve as early detection of viral circulation modulating the control of blood donors can substitute the evaluation of areas based on the viral circulation of the previuos year/s At the following conditions..

33 .conditions all the lowland (< 100m s.l.m.) is divided in regular grid (from 10 to 20 km) at least one trap in each grid collection of mosquitoes every 15 days (or even per week ) pool of mosquitoes not more than 200 specimens (loss of sensitivity) rapidity of the system: from collection to detection of the virus 14 days max. (less is better)

34 In other words The success of your system will depend trap coverage of the area intensity of collections budget

35 In conclusions to provide the right balance between financial resources and protection of public health the money saved can be invested in additional interventions focusing on vector mosquitoes..

36 In collaboration with.. Istituto Zooprofilattico Sperimentale della Lombardia e dell Emilia Romagna B. Ubertini M. Dottori, M. Chiari, M. Tamba, D. Lelli, M.Calzolari Istituto Zooprofilattico Sperimentale delle Venezie F. Montarsi, L. Bonfanti, I. Monne, S.Ravagnan, P. Mulatti, M.Mazzucato Istituto Zooprofilattico Sperimentale Piemonte Liguria Valle d Aosta C. Casalone, A. Pautasso, L. Chiavacci, C. Radaelli Centro Agricoltura Ambiente G.Nicoli R. Bellini, A. Albieri Regione Emilia-Romagna P Angelini, S. Natalini, A.C. Finarelli, R. Cagarelli, A. Mattivi, C. Velati Regione Lombardia P. Frazzi, M. Gramegna, A. Piatti, M. Farioli, D. Rossi Regione Veneto F. Russo, F. Zanella, A. Breda, G.Cester Regione Friuli Venezia-Giulia N. Coppola, M.Palei Regione Piemonte V. Demicheli

37 Thank you for your attention