Importanza sanitaria degli ectoparassiti

Domenico Otranto d.otranto@veterinaria.uniba.it http//www.bariparasitology.it

Impatto delle malattie parassitarie nella vita comune...

COS’è UN PARASSITA?

livelli di interazione tra essere viventi SIMBIOSI

livelli di interazione tra essere viventi COMMENSALISMO

livelli di interazione tra essere viventi PARASSITISMO

parà=presso; sìtos=cibo simbiosi antagonista tra ospite e parassita, il quale vive o nell’ospite o su di esso, arrecandone un danno diretto o indiretto. CO-EVOLUZIONE/EFFICIENZA BIOLOGICA DINAMICA DI POPOLAZIONE SOCIALIZZAZIONE

PROTOZOI METAZOI

Platelminthes, Acantocephala, Nematoda, Pentastomida,

Arthropoda

CICLO BIOLOGICO

insieme delle fasi vitali che

coinvolge tutte le diverse

generazioni di una specie. Si

susseguono tra loro durante la

riproduzione, asessuata e

sessuata, con lo sviluppo di nuove

forme infettati. Durante il ciclo

possono alternarsi più morfotipi

dello stesso parassita.

…key words…

OSPITE Organismo in cui il parassita svolge una o più fasi del suo ciclo vitale. - INTERMEDIO ospite in cui il

parassita svolge la fase asessuata del ciclo vitale

- DEFINITIVO ospite in cui il parassita svolge anche la fase sessuata del ciclo

- TERMINALE ospite in cui il ciclo viene interrotto

- PARATENICO ospite in cui il parassita non compie parte del ciclo biologico, ma aspetta…

…key words…

VETTORE BIOLOGICO

Artropode in cui il parassita

svolge una fase (di solito

riproduttiva) del ciclo vitale

VETTORE MECCANICO

…key words…

ZOONOSI

“Malattie trasmissibili dagli

animali vertebrati all’uomo e

viceversa”

…key words…

Temperatura

Umidità

Fonte: G.V. Kolonin. Fauna of ixodid ticks of the world (Acari: Ixodidae). Moscow, 2009.

Interaction between veterinary and human medicine (clinicians, researchers, governments); Management of zoonotic infectious disease outbreaks in the field; Joint research programmes to integrated policy making and funding decisions.

Day MJ. Parasit Vectors. 2011 13;4:49.

‘One Health’

17% of total number of infectious diseases transmitted by arthropods last decades global emergence and resurgence of many ABD in human and animal populations human health and economy heavily affected by ABDs CVBDs

WHO, 2004.

Colwell et al., 2011

1) global increase canine population (about 10% of the human population);

2) social importance of dogs in developed countries (assistance to people with physical & mental illnesses, humans with disabilities); 3) increase co-habiting dogs and humans (urban and rural env.);

4) competent reservoirs and easily available food source for pathogens and arthropods (animal welfare & public health).

Zoonotic CVBDs

Law n. 281 14th August 1991 “Companion Animals and Prevention of Strays”

- Stray dogs: 75% of canine population worldwide; - Easy feeding source for arthropods, reservoir of pathogens

Leishmaniosi canina (CanL)

NOTE STORICHE - segnalata già dal 650 a.C. - Leishman e Donovan (1900)

Eziologia Ciclo biologico Epidemologia

Distribuzione della CanL in Italia I vettori e la loro stagionalità (rischio)

..non chiamateli zanzare…

Piccole dimensioni (2-3 mm)

Colore giallo pallido o ruggine

corpo e ali ricoperti da fitta peluria

Morfologia

Necessitano di un pasto di sangue

per la maturazione delle uova.

Telmofagia Solenofagia

Dove non ci sono flebotomi non può esserci leishmaniosi endemica

Diffusione leishmaniosi nel mondo

prima del 1989

nuovi focolai autoctoni sospettati

CL in Italia

nuovi focolai autoctoni provati

L. Infantum si sta diffondendo dalle regioni costiere centromeridionali e delle isole, considerate tradizionalmente endemiche, a quelle centrosettentrionali con focolai anche nelle aree collinari alpine e preappenniniche.

Comportamento

dell’ospite

Puntura indolore

Volo notturno, silenzioso

(pappataci) e breve.

In zone indenni: reazione allergica e

cefalea.

Reazione cutanea locale con prurito e una papula

Courtesy of A.Giannelli

- 72/88 countries are developing; - 0.2 to 0.4 million VL & 0.7 to 1.2 million CL each year; - 20,000 to 40,000 leishmaniasis deaths each year (probably underestimated!). - VL (90% India, Bangladesh, Sudan, South Sudan, Brazil, and Ethiopia).

- CL (75% Afghanistan, Algeria, Colombia, Brazil, Iran, Ethiopia, North Sudan, Costa Rica, Peru);

Alvar et al., 2012

Dantas-Torres et al., 2012

Global burden of leishmaniasis

morbidity and mortality

VL & HIV

VL opportunistic infection associated with HIV (mutual reinforcement); Endemic areas, many people asymptomatic infection; Concomitant HIV infection > risk of developing VL 100 and 2320 times; Southern Europe: up to 70% VL in adults associated with HIV; High risk of treatment failure for VL is high.

Alvar J et al., The relationship between leishmaniasis and AIDS: the second 10 years. Clin Microbiol Rev. 2008; 21:334-59 http://www.who.int/leishmaniasis/en/

Controllo della popolazione

del vettore

Limitazione dei contatti

flebotomo-cane

Cani al chiuso durante la notte (tramonto e prime

ore del mattino)

Trappole ed insetticidi (crepe dei muri)

Vaccini ?

Sostanze repellenti

futuro Leishmaniosi: COSA RESTA DA FARE

?

…ai parassiti piace viaggiare…

Aedes albopictus

(no, non è una parolaccia)

VB

EN

AG

TP

42°

1990

VB

EN

AG

TP

42°

Commercial port of Venice

A container of used tyres from Atlanta (USA) was found positive for larvae and eggs of Ae. albopictus

batches of tyres were distributed to smallest companies in other regions of Italy…

1990

VB

EN

AG

TP

Distribution of Aedes albopictus in Italy (by Provinces)

2001

42°

Data provided by Roberto Romi ISS, Rome (March 2009 )

VB

EN

AG

TP

2004

42°

Data provided by Roberto Romi ISS, Rome (March 2009 )

Distribution of Aedes albopictus in Italy (by Provinces)

VB

EN

AG

TP

2009

42°

Data provided by Roberto Romi ISS, Rome (March 2009 )

Distribution of Aedes albopictus in Italy (by Provinces)

VB

EN

AG

TP

2011

42°

Data provided by Roberto Romi ISS, Rome (June 2010)

Distribution of Aedes albopictus in Italy (by Provinces)

Ae. albopictus adapted to the low winter Italian temperatures: increased its populations (insects generations over the whole year in C and S; overwintering as eggs in colder N)

Current (2009) distribution of Aedes albopictus in Europe by administrative unit

THE FUTURE

-A. albopictus population is expected to expand northwards - few entomological studies (basic research and surveillance)

Overwintering expanding populations; purple: populations observed indoors; green: not detected in past 5 years; pale yellow: no recent data on mosquito fauna; blue: no information on any mosquito studies; white: not included in this study. (ECDC, 2010)

The majority of the 492 cases reported in Europe, from Italy (117) and, in particular, from Sicily t(Video: D. repens under the skin of a dog. University of Bari, Italyhe conjunctiva or eyelid

(Pampiglione et al., 1995; Pampiglione et al. 2009; McCall et al., 2008; Genchi et al., 2011)

Dirofilaria repens

Human case of ocular infestation by D. repens

from the province of Trapani (endemic for canine dirofilariosis)

Relationship between occurrence of canine infestation and human cases of dirofilariosis (on the basis of the review of the historical literature)

Otranto et al., AJTMH 2011

Le principale malattie transmessa da zanzare

Arboviroses: -Dengue - Dengue emorragica - Febre gialla

unbranched caeca that isunique to N. namaqua [12,22]. The semi-filled state of the gut indicated that this tick fed in the recent past,but its partial depletion indicated that it has started to process its

blood meal (Fig. 2F). Rupture of the gut showed the presence ofnumerous hematin crystals. A Giemsa stained smear preparedfrom extruded gut contents showed the presence of intactnucleated red blood cells(Fig. 2G). A second female wasdissected,but its gut contents did not show the presence of any intactnucleated red blood cells.

Identification of previous hosts from the gut contentNucleated red blood cells in the gut indicated that a previous

blood meal was obtained from an avian or reptilian host [23].Given the collection locality, it was unlikely that birds could behosts, while numerous lizards were observed at the collection site.However, to ensure detection of both avian and reptilian hosts,primers for the 16S mitochondrial gene that amplifies lizard andavian gene fragmentswere used [24]. Thisstrategy wasfollowed asit is known that nucleated red blood cells retain mitochondria inlower vertebrates [25]. Sequencing of twenty-six different clonesyielded four different 16S rRNA gene fragments (contig 1: 12,contig 2: 5, contig 3: 6, contig 4: 3 sequences, respectively).BLASTN analysis retrieved members of the girdled lizard family(Cordylidae) with E-values of zero. Neighbor-joining analysisindicated that contig 1 group within the Karusasaurus clade andpossibly represents Karusasaurus polyzonus. Contig 2 and 4 groupedwith weak support within the Cordylus clade with no distinctsimilarities to any of the lizard sequencescurrently available in thedatabases (Fig. 3). Similarly, contig 3 grouped in a clade formed bythe genera Ninurta and Pseudocordylus, but with no distinct similarityto any lizard sequencescurrently deposited. The gut contents froma second dissected tick did not show any intact red blood cellsandno PCR products were obtained from extracted DNA. Neitherwas any amplification products detected for DNA extracted fromlarvae.

Tick feedingThe identification of lizards as potential hosts prompted the

feeding of N. namaquaon lizards. Both nymphsand adultsattached,probed and fed without engorgement. One nymph attached andfed slowly for , 3 hours before rapid engorgement, which took, 20 minutes and then remained attached for , 60 minutes. Fouradult females attached and became engorged within 20 minutes.Rapid feeding coincided with rapid expansion of the leatherycuticle asobserved for soft ticks (Fig. 2D). A period of slow feedingfollowed that lasted for 30–120 minutes, during which dropletswere expunged from the anal opening and spurtswere observed tooccur in a rhythmic manner, with an appreciable amount of fluidbeing secreted (estimated at 30 nl/ 10 seconds). One tickexpanded to a fully engorged state in which even the smallinfoldings of the integument became distended (Fig. 2D). En-gorged weights increased , 5–14 times compared to the unfedweight. The female that engorged to the greatest extent, ingested, 14 ml final volume (w/ v basis), assuming a density of blood of1.06 g/ ml [26]. It also remained attached in the engorged phasefor one hour during which time fluid secretion occurred. Asecretion rate of 30 nl/ 10 s was calculated based on droplet sizeexcreted, resulting in , 11 ul of fluid secreted. This would makethe final volume of ingested blood , 25 ml and would indicate thatthe blood meal was concentrated approximately two fold.Excretion of fluid terminated immediately upon detachment fromthe host and was not observed for up to an hour after feeding.

Tick systematicsThe small ribosomal nuclear RNA (18S rRNA) gene is the

most commonly used molecular marker for the investigation ofarthropod and chelicerate relationships at the level of phyla and

Figure 2. Collect ion and morphology of N. namaqua. A) Thecrevice from which specimens were collected. B) A specimen concealedon a rock obtained from within the crevice. C) A dorsal view of an unfedfemale that shows the pseudo-scutum and ventral mouthparts. D) Thesame tick shown as an engorged female still attached to a lizard. E) Sizerange and general morphology of the collected live specimens. Theblack arrow indicates the tick selected for dissection from which lizardDNA was extracted. F) A dissected female with midgut that indicates it’srecently fed status. G) A Giemsa stained smear obtained from the gutcontents of the dissected female.doi:10.1371/journal.pone.0023675.g002

Nuttalliella namaqua: A Living Tick Fossil

PLoS ONE | www.plosone.org 3 August 2011 | Volume 6 | Issue 8 | e23675

898 specie suddivise in 3 famiglie: - Ixodidae (zecche dure) 14 generi,703 specie - Argasidae (zecche molli) 5 generi, 194 specie - Nuttalliellidae 1 specie

ciclo Ixodidae elevata plasticità biologica: possibilità di diapausa in ogni stadio in condizioni naturali, lunghezza ciclo variabile...

Accoppiamento zecche

RUOLO PATOGENO Azione meccanica e chimica (reazione di ipersensibilità) ematofagia Inoculazione di tossine Trasmissione di agenti patogeni

Ixodes ricinus sottrae fino a 0.6 g di sangue

Amblyomma spp. sottrae circa 8 g di

sangue

RUOLO PATOGENO: vettori!

• CKF virus • PSA virus • tick borne

encephalitis virus

• Borrelia spp • Rickettsia spp • Coxiella burneti • Anaplasma spp • Bartonella spp

• Hepatozoon spp • Ehrlichia spp • Trypanosoma spp • Babesia spp • Theileria spp

Malattia di Lyme

Borrelia burgodrferi s.l.

78

Characteristic spotted rash of late-stage Rocky Mountain spotted fever on legs of a patient, ca. 1946

Tick Sampling

ricerca sull’ ospite Dragging/flagging

Tick walking

importanza corretto campionamento

Tick Control a. Lotta biologica

• Controllo meccanico

• vaccini: TickGUARD

• Acaricidi •growth regulator factors

•Vestire abiti con colori chiari

•Calzari o inserire estremità pantaloni nei calzini

•Applicare repellenti DEET (n-diethyl-m-toluamide) sulla pelle (breve durata) o sui vestiti

AVOIDING TICKS

• Check ya body!

AVOIDING TICKS - II

84

Come rimuovere una zecca

Tick Removal cosa non fare

• Non spremere, schiacciare, forare o rompere la zecca

• Non applicare benzina, anestetici, alcol sulla zecca

• Non dare fuoco all’animale

Ten years of studies at the Faculty of

Veterinary medicine of Bari:

Thelazia callipaeda & its vector

Thelazia callipaeda from “oriental eyeworm” to

“new emergent” parasite for Europe

.

Indonesia (Kosin et al., 1989)

. . . .

Thailand (Bhaibulaya et al., 1970) . . India (Singh and Singh, 1993) . Taiwan (Cheung et al., 1998)

China (Chen et al., 1954)

Soviet Union (Miroshnichenko et al., 1988 )

Japan (Koyama et al., 2000)

Korea (Min et al., 2002)

Bari

. In dogs in Piedmont (Rossi and Bertaglia, 1989. 31: 167-172)

. In dogs, cats and foxes in southern and northern Italy (Otranto et al., 2003. Vet. Parasitol., 116: 315-325)

.

Mean prevalence of 42.3% in dogs of Basilicata (up to 60.14%) (Otranto et al., 2003. Vet. Parasitol., 116: 315-325)

? On the tracks of the “oriental eyeworm in Europe”

Only recently reported in Europe (provenience?) 1) from Asia with a definitive host; 2) the vector harbouring infective larval stages of T.c. imported from the Far East; 3) autochthonous infection?

Molecular epidemiology genetic identity of vectors in a given area

Probably T. callipaeda was imported from Asia and (h1) spread throughout Europe in close association with the vector (Phortica variegata) (Otranto et al.,

2005a, b; 2006)

Otranto, et al. 2004. Parasitology 129: 627-633

Highest number of Phortica collected in July -August (at 20 -25°C; 50 -75% relative humidity)

Mathematical models, remote sensing and geographical inf. syst.

Ecological niche modelling, distributional data, representing 242

sites in which P. variegata were collected in Europe

The most robust model: the Genetic

Algorithm for Rule-Set Prediction

Predictive model of the potential ditributional niches of P. variegata (in grey)

In 2005 the ecological niche model suggested that large areas of Europe were likely

to be suitable habitat for this species

…From “oriental eyeworm” to “new emergent” parasite in Europe”…

. Germany (Hermosilla et al., 2004)

France (Chermette et al., 2004; Dorchies et al., 2007, Ruytoor et al., 2010) . .

Switzerland (Schinider et al., 2007 Malacrida et al. 2008)

. .

Spain (Dogs and cats: Mirò et al., 2011)

. . . .

. . Pourtugal (Dogs: Vieira et al. 2012; Cats: Rodrigues et al., 2012)