VECTOR-SURVEILLANCE IN

NORTHERN ITALY

Vienna, 8 giugno 2015

Gioia Capelli

Laboratorio di Parassitologia

Istituto Zooprofilattico

Sperimentale delle Venezie

tel 0039 049 8084374

gcapelli@izsvenezie.it

www.izsvenezie.it

Stechmücken: Belästigung oder Bedrohung?

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

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

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

http://sorveglianza.izs.it/emergenze/west_nile/emergenze.html

WNV the regional plans ER and VEN-FVG

ER sistematic trapping every10 km (now

11km)

VEN-FVG risk-based

ER

VEN-FVG

WNV the regional plans Piemonte and

Lombardia

methods

Mosquito collection every 15 days

Mainly CDC-CO2 traps

Pooled mosquitoes (50-200)

Molecular viral research

gravid trap CO2 trap BG Sentinel

An idea of the numbers…2013

757,461 mos collected

562,079 pooled for PCR

(Calzolari et al., under revision)

Ento results 2013 in a map

Calzolari et al., in revision

Mosquito infection rate MIR (Veneto)

year Rate of infection WNV

min-max

Pool pos

WN1

Pool pos

WN2

2010 0.056-2.714 10 -

2011 0.984-2.535 2 1

2012 0.052-0.946 10 1

2013 0.056-3.448 2 55

2014 0,150-1,418 - 7

dati IZSVe-Regione Veneto and FVG

Mosquitoes and human infection

Not only mosquitoes…..

Mosquitoes and equines 2013

WNV: early detection of viral circulation

How predictive is the mosquito positivity?

The vector index (Veneto 2012)

R=0.843, p< 0.01

Can we really prevent human cases?

http://www.examiner.com/article/organic-produce-does-have-health-benefits

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 ?

Entomologial results vs human and veterinary cases

(pos/tested – data first recovery WNV)

Emilia Romagna (ER) region

Entomologial results vs human and veterinary cases

(pos/tested – data first recovery WNV)

VENETO region Anno

( n traps)

2009 2010

(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 (09-12-20-

25/09)

14 (15/07, 03-09-10-

18/08, 04-21/09)

7 (22-23-29/08,

04-13-14-26/09)

1 (09/09)

Province level ER 2013-2014

PR

OV

Data first human case First pool of

mosquitoes

pos WNV

Days in advance mosq pos vs

human cases and donors First symptoms

WNND

First symptoms

WNF

First donor

pos WNND BLOOD

MO 03/08 14/08 3/08 03/07 31 31

FE 06/08 13/09 1/09 17/07 20 45

BO 15/08 24/08 25/08 17/07 29 39

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 5/08 26 28

Province level VENETO 2013-2014

PV

Data first human case First pool

of

mosquitoes

pos WNV

Days in advance mosq pos vs

human cases and donors First symptoms

WNND

First

symptoms

WNF

First donor

pos WNND-WNF BLOOD

VE 01/09 - 22/08 03/07 58 49

TV 16/08 14/08 - - human only -

RO 21/07 24/07 14/09 17/07 4 57

VR 04/08 04/08 23/08 17/07 16 36

VI - - - - - -

PD 11/08 - 29/08 - human only -

VE - - - - - -

TV - - - - - -

RO - - 09/09 04/08 mos only 35

VR 12/08 16/08 - 04/08 8-12 -

VI - - - 08/07 mos only -

PD - - - - - -

Summary northern Italy 2014

REGIONE / PROVINCE Prima positività

entomologica

Prima positività

ornitologica

Data esordio

sintomi primo

caso WNND

Giorni di anticipo della

positività entomologica

Giorni di anticipo della

positività ornitologica

(dt inizio sintomi -data pos

entomologica)

(dt inizio sintomi -data pos

ornitologica)

LO

MB

AR

DIA

Bergamo 15/09/2014 20/08/2014 - - -

Brescia 08/07/2014 04/08/2014 06/09/2014 60 33

Cremona 11/08/2014 11/08/2014 22/08/2014 11 11

Lodi 24/07/2014 - 27/08/2014 34 -

Milano 02/09/2014 02/09/2014 - - -

Mantova 11/08/2014 30/07/2014 03/09/2014 23 35

Lecco - 22/092014 - - -

Pavia * 02/09/2014 - 13/08/2014 -20 -

EM

ILIA

-RO

MA

GN

A

Piacenza 11/08/2014 08/09/2014 03/09/2014 23 -5

Parma 10/07/2014 11/07/2014 25/08/2014 46 45

Reggio Emilia 05/08/2014 23/07/2014 27/08/2014 22 35

Modena 28/07/2014 31/07/2014 20/08/2014 23 20

Bologna 14/07/2014 23/09/2014 25/08/2014 42 -29

Ferrara 11/08/2014 14/08/2014 - - -

Ravenna 16/09/2014 24/09/2014 - - -

Alessandria 27/08/2014 - - - -

VE

NE

TO

Venezia - - - - -

Treviso - - - - -

Rovigo 04/08/2014 - - - -

Verona 04/08/2014 - 12/08/2014 8 -

Vicenza 08/07/2014 - - - -

Padova - - - - -

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)

Identification-

pooling (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) 9378 14086 11134 31185

Reagents,

consumables ,

travel (EUR) 12599+8667 500 62138 -

Total (EUR) 30644 14586 73272 31185

Is the screening of donors necessary?

Pupella et al., 2014 Update on West Nile virus in ItalyBlood Transfusion 12(4): 626–627

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.”

Pupella et al., 2014 Update on West Nile virus in Italy

Blood Transfusion 12(4): 626–627

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. 2014 Blood Transfus.; 11(4): 563–574

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

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)

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…..

….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)

In other words…

The success of your system will depend

• trap coverage of the area

• intensity of collections

•budget

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…..

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

In collaboration with…..

Thank you for your attention