Educational Workshop

EW10: Emerging parasites arranged with ESGCP (ESCMID Study Group for Clinical Parasitology)

Convenor: Eskild Petersen (Arhus, DK)

Faculty: Joaquim Gascon (Barcelona, ES) Edoardo Pozzi (Rome, IT) Eskild Petersen (Arhus, DK) Peter Deplazes (Zurich, CH)

Gascon –Chagas‘ disease

Chagas Disease

Joaquim Gascon Centre Salut Internacional Hospital Clínic de Barcelona

Helsinki, May 2009

LYFE CYCLE

Chagas is a zoonotic disease

Endemic to LatinAmerica

The vector and the parasite

The triatomine. Domestic and peridomestic environments in rural dwellings and domestic animals

From: Carlomagno M, et al. 1989 The parasite. Two major groups: T.cruzi I (widespread but the only form north of the Amazon region) T.cruzi II (Southamerica. Associated with digestive tract lesions).

Both groups associated with cardiac lesions

3 Gascon –Chagas‘ disease

Ó TRANSMISI N

Routes of transmission

. Vectorial transmission (triatomine bite)

. Vertical transmission (pregnancy, delivery) . Transfusion or trasplants. . Oral transmission through contaminated food/beverages

Phases of Chagas Disease

Subacute cases Acute Form deaths 5-10% (<50% symptomatic) 2-3%

Indeterminate Form

(no symptoms, and no pathologic changes detected by ECG, Rx, esofagogram or barium enema)

60% of infected people Digestive Chronic Cardiac Chronic Form Chronic Forms Form 10-20% 20- 30%

CHRONIC FORMS OF CHAGAS

Cardiac Chronic Form Digestive Chronic Form (fibrosing cardiopathy and (loss of neurons in the gut and inflammatory lesions) inflammatory lesions)

Dilated miocardiopathy Megaesophagus congestive failure Megacolon

Rhythm disturbances Other megaviscera Thromboembolism.

4 Gascon –Chagas‘ disease

T.cruzi Infection prevalence in Latin-american pregnant women in Barcelona*

*2 Maternities : HCB & H. St. J. de Deu Fac Farm UB COUNTRY N (total: 1350) POSITIVE SAMPLES (%)

BOLIVIA 166 42 (27.5%)

ARGENTINA 90 2 (1.1%)

PERU 204 1 (0.58%)

ECUADOR 435 0

COLOMBIA 137 1 (0.73%)

CHILE 36 0 Screening URUGUAY 32 0 Lab test

PARAGUAY 32 0 ELISAr (Biokit) VENEZUELA 33 0

TOTAL 1350 46 (3.4%) 3 + newborn (7.3%)

Muñoz J. et al, Clin Infect Dis, in press

Results of the study in the Blood Banks in Catalonia*

*BSTC / Fac Farm UB / HCB Serological Prevalence In latinamerican blood donors: 10/1524 (0.66%)

6/10 were bolivians (10% of 59 bolivian donors)

In spanish travellers / migrants / expatriates living >1 month in endemic areas 1/ 250 (0.42%)

Piron M. et al. Transfusion 2008

5 Gascon –Chagas‘ disease

Chagas Disease in Barcelona

*HCB / UMTISI Drassanes. / Fac Farm UB April/07 Studies in Specialized Imported Diseases Centers, Barcelona

- 171/458 (37%) infected by T.cruzi (Bolivia: 86%) (4.6% were blood donors in Barcelona).

Clinical features: 23% ECG alterations (N= 39). 1 sudden death. 1 in the cardiac trasplant programme 8% with GI tract pathology (N=14) 6 immunodepressed patients

Muñoz J. et al, Acta Tropica in press

EUROPEAN CASES OF CHAGAS DISEASE May / 08 • Italy: 22 cases - 1 acute case (traveller) - 1 reactivation - 2 chronic cardiac forms - 1 chronic digestive form

• France: 18 cases (Paris) - 7 chronic cardiac forms - 1 acute case

• Germany / UK / Portugal: no cases reported (or anecdotic)

• Sweden 2-4 cases/year reported Switzerland: 28 cases • Spain: >500 cases

Estimated cases of Chagas in Europe

From: Guerri-Guttenberg RA. Eur H J, 2008

6 Gascon –Chagas‘ disease

Latinamerican immigration by country in Spain 2008

ESTIMATED Nº of ESTIMATED T.cruzi ESTIMATED INFECTED COUNTRIES MIGRANTS PREVALENCE MIGRANTS

ARGENTINA 287,760 4,13% 11,882 BOLIVIA 238,605 6,75% - 15% 16,106 –35,791

BRASIL 140,942 1,02% 1,436 CHILE 66,270 0,99% 653

COLOMBIA 326,459 0,96% 3,121

ECUADOR 451,072 1,74% 7,844 MEXICO 42,413 1,03% 436

PARAGUAY 68,234 2,54% 1,735

PERU 160.603 0,69% 1,102

URUGUAY 86,601 0,66% 568 VENEZUELA 142,709 1,16% 1,654

TOTAL 2,090,000 47,738 –67,423

DIAGNOSIS OF CHAGAS DISEASE

Acute cases: Parasitological tests Thick blood film Strout Microhematocrit (newborns) Hemoculture Molecular test PCR

Chronic / Indeterminate forms:

Serology (two tests with different antigens) ELISA, IHA, IFI

TREATMENT

Benznidazol and Nifurtimox are the only drugs currently availables for Chagas disease . treatment

Both have a poor profile for side effects (~ 10% severe) - cutaneous (rash, urticaria, pruritis) - polineuritis - gastrointestinal disturbances

High efficacy in acute cases, but the efficacy declines with the duration of infection

7 Gascon –Chagas‘ disease

CONCLUSIONS

What does Europe need?

To better evaluate the emergence of Chagas disease in the Continent -prevalence -burden of disease

To implement public health policies to prevent/control Chagas transmission - blood transfusion - organ transplantation - mother-to-child

CONCLUSIONS

The European health care community has the opportunity to contribute to the general knowledge of Chagas disease and to promote research in this field.

8 Summary

Trichinella infection and trichinellosis E. Pozio (Rome, IT)

Nematode worms belonging to the genus Trichinella are the etiological agent of a zoonosis named trichinellosis. These parasites are widespread in wildlife on all continents but Antarctica, and in domestic pigs of many countries. Infections occur in humans where cultural food practices include dishes based on raw or undercooked meat and meat products of different animal origins (e.g. pork, horse, game); thus, cultural factors such as traditional dishes based on raw or undercooked meat play an important role in the epidemiology of the disease. When a population uniquely consumes well-cooked meat, trichinellosis cases are lacking or very scarce despite persistent wildlife transmission. Human trichinellosis has been documented in 55 (27.8%) countries around the world. In several of these countries, however, trichinellosis affects only ethnic minorities because the native inhabitants do not consume uncooked meat or meat of some animal species. Trichinella sp. infection has been documented in domestic animals (mainly pigs) and in wildlife of 43 (21.9%) and 66 (33.3%) countries, respectively. At present, eight species and four genotypes are recognised in the genus Trichinella. The parasites are perpetuated in life-cycles with carnivorous and omnivorous animals representing the most important reservoir. All species can develop in mammals, but T. pseudospiralis can also develop in birds, and two species also occur in crocodiles and monitor lizards. No morphological differences exist between species and genotypes, and they are most reliably distinguished by biochemical or molecular analyses. A peculiarity of the cycle of these worms is the development of two generations in the same host. The average yearly incidence of the clinical disease in humans worldwide is probably close to 10,000 cases with a mortality rate of about 0.2%; however, the number of infections is underreported in many countries due to the lack of appropriate serological tests and a lack of knowledge of the disease on the part of physicians. Trichinellosis usually begins with a sensation of general discomfort and headache, increasing fever, chills and sometimes diarrhoea and/or abdominal pain. Pyrexia, eyelid or facial oedema and myalgia represent the principal syndrome of the acute stage, which can be complicated by myocarditis, thromboembolic disease and encephalitis. The clinical signs and symptoms are directly related to the parasitic cycle in the human host.

10 Pozio - Trichinellosis

Trichinellosis

Edoardo Pozio

Community Reference Laboratory for Parasites Istituto Superiore di Sanità Rome, Italy

19th ECCMID, Helsinki, Finland 16-19 May, 2009

What is trichinellosis?

•It is a zoonotic disease caused by nematode worms of the genus Trichinella •Humans acquire the infection by the consumption of raw or semi-raw meat or meat derived products of pig, horse or game

Introduction to the Trichinella world • What is Trichinella – a genus of nematode worms (round worms), which infect vertebrates including humans

100 mm – these parasites were discovered by Owen in U.K. in 1835

– etiological agent of a serious human disease named trichinellosis

– they show a cosmopolitan distribution

11 Pozio - Trichinellosis

The life cycle

Taxonomy of the genus Trichinella

• Non-encapsulated • Encapsulated species species – T. pseudospiralis – T. spiralis – T. papuae – T. nativa, – T. zimbabwensis Trichinella T6 Trichinella T12 – T. britovi, Trichinella T8 – T. murrelli, Trichinella T9 – T. nelsoni

World map of Trichinella spiralis

12 Pozio - Trichinellosis

Geographical distribution of encapsulated species of Trichinella transmitted by a sylvatic cycle

T12

Geographical distribution of non-encapsulated species of Trichinella

World distribution of Trichinella and trichinellosis

• Human trichinellosis has been documented in 55 (27.8%) countries • Trichinella sp. infection has been documented in: – domestic animals (mainly pigs) of 43 (21.9%) countries – in wildlife of 66 (33.3%) countries

13 Pozio - Trichinellosis

Trichinella spp.

– four species are circulating in Europe: • T. britovi is the most widespread species in Europe; it has been detected in 23 MS, but not in Cyprus, Ireland, Malta and United Kingdom • T. spiralis has been detected in 16 of 27 MS (Austria, Bulgaria, Estonia, Finland, France, Germany, Hungary, Ireland, Poland, Latvia, Lithuania, Slovak rep., Romania, Spain, Sweden and United Kingdom) • T. nativa has been detected in Estonia, Finland, Latvia, Lithuania and Sweden • T. pseudospiralis in Bulgaria, Denmark, Finland, France, Germany, Hungary, Italy, Slovak Rep and Sweden

Distribution of T. britovi and T. spiralis in EU

Clinical trichinellosis

Average incidence of Country Incidence x acquired abroad or for clinical trichinellosis 100,000 consumption of inhabitants imported meat in the 27 EU Bulgaria 3.6 0 countries x 100,000 Estonia 0.15 0 inhabitants France 0.01 54% Germany 0.01 83% Hungary 0.02 0 Italy 0.01 65% Latvia 2.3 0 Lithuania 1.08 0 Poland 0.22 0 Romania 3.7 0 No infection has been documented in Austria, Belgium, Cyprus, Czech Slovak Rep. 0.03 0 Rep, Denmark, Finland, Greece, Spain 0.07 0 Ireland, Luxembourg, Malta, Sweden 0.02 100% Netherlands, Portugal and Slovenia UK 0.005 100%

14 Pozio - Trichinellosis

The clinical disease - 1

• The enteral phase – it is frequently asymptomatic – the main symptoms are: • diarrhoea • abdominal pain • vomiting • The parenteral phase – the acute stage with the sudden appearance of general discomfort, severe headaches, fever, chills and excessive sweating – the major syndrome of the acute stage consists of persistent fever, facial oedema (periorbital, facial and oedema of limbs), muscle pain, and severe asthenia, lasting for several weeks

Main clinical features of human trichinellosis - 1

Features % of frequency in Length outbreaks

Diarrhea and flatulence 0-40% 1-7 d (up to 3 w) Abdominal pain 6-60% 1-7 d Loss of appetite 70-85% 2-4 w Vomiting 5-10% 1-2 d General weakness 85-97% 1-4 w Headache 80-90% up to 5 w Fever (up to 40°C) 41-100% 1-2 w Excessive sweating 45-60% 1-2 w Eyelid edema 80-90% 5-7 d Periocular edema 17- 100% 5-7 d

Main clinical features of human trichinellosis - 2

Features % of frequency in Length outbreaks Eye pain upon ocular movement 77% 5-7 d Facial edema 43-88% 5-7 d Edema of limbs 6-8% 5-7 d Cutaneous rash 4-51% 3-5 d Petechiae 2-12% 2-4 d Intraconjunctival hemorrhages 56-73% 3-5 d Hemorrhages of nail beds 49-65% 3-5 d Myalgia 59-97% 2-3 w Myocarditis 5-20% 1-2 w Neurological complications 3-60% 2-4 w

15 Pozio - Trichinellosis

The clinical disease

Periorbital oedema Facial oedema

Oedema of fingers

Subungual haemorrhages

Ocular haemorrhages Oedema of lower limbs

Main laboratory features of human trichinellosis

Features % of frequency in Length outbreaks Eosinophilia (up to 19,000 99% 1-10 w cells per mm3) Leukocytosis (up to 50,000 99% 1-8 w cells per mm3) Increased CPK 75-90% 3-7 w Increased LDH 60-80% 2-6 w Seroconversion 100% 2-8 w

Clinical complications in the course of trichinellosis

• Cardiovascular – myocarditis – thrombophlebitis • Neurological – encephalopathy – decreased muscular strength and tendon reflexes – dysphagia – Trismus • Ocular

• Respiratory – Dyspnea • Digestive – massive protein exudation leading to hypoalbuminemia and localised oedemas – acute intestinal necrosis – prolonged diarrhoea

16 Pozio - Trichinellosis

Diagnosis of human infection

• Parasitological diagnosis on muscle biopsy

• Serological diagnosis (ELISA, Western blot) with a highly specific test which uses excretory/secretory antigens

• Clinical diagnosis

Detection of Trichinella larvae in muscle biopsy

•Trichinoscopy

•Digestion

•Histology

Treatment

• The principal anthelmintics used for trichinellosis are: – mebendazole (VermoxÒ, Janssen) (25 mg/kg/day administered in three doses for 10-14 days) – albendazole (ZentelÒ, GlaxoSmithKline) (15 mg/kg/day administered in two doses for 10-15 days) • Symptomatic treatment – glucocorticosteroids are used in combination with anthelmintics, to treat the signs and symptoms (e.g. prednisolone 30-60 mg per day, in multiple doses, for 10-14 days)

17 Pozio - Trichinellosis

Prevention - 1

• education of the consumer about the risk of consumption of raw or semi-raw meat and meat products from both domestic (e.g., pigs, horses, and dogs) and wild animals • control of all susceptible animals by a standardized artificial digestion method at slaughtering or after hunting • curing and smoking processes are not recommended to inactivate Trichinella larvae in pork, horse, or game meat

Prevention - 2

• all meat which might contain Trichinella larvae, but cannot be tested by an appropriate laboratory method, should be treated by – cooking to reach a core temperature of not less than 71°C for at least 1 min – freezing (cuts of meat up to 15 cm in thickness are frozen solid, at least -15°C, for no less than 3 weeks (this only for pork not for game meat)

Thank you for your attention

18 Petersen –Fasciolosis and opistorchiasis

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

Opistorchis

Eskild Petersen

Department of Infectious Diseases Aarhus University Hospital, Skejby Denmark

ProMED co-editor Parasitic Diseases

Specialist of Infectious Diseases and Tropical Medicine Department of Infectious Diseases, Aarhus University Hospital

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

19 Petersen –Fasciolosis and opistorchiasis

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

It has been estimated that 2 million in the former Soviet Union might be infected. Benenson, 1995 (Control of communicable diseases manual, APHA)

Several Russian studies published in Russian for instance:

Opisthorchiasis in the hyperendemic focus (Ob-Irtysh river basin)

Bychkov et al. Med Parazitol (Mosk). 2007;Oct-Dec:3-5.

Opisthorchiasis in the Kemerovo Region

In the Kemerovo Region, the incidence of opisthorchiasis increased among adults and children from 44.0 in 1995 to 78.2 per 100,000. The high risk of Opisthorchis infection in children aged less than 14 years has recently increased from 17.2 to 35.0.

Nacheva et al. Med Parazitol (Mosk). 2007;Jan-Mar:25-8.

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

Cercariae are released from the snail and penetrate freshwater fish (second intermediate host), encysting as metacercariae in the muscles or under the scales.

The mammalian definitive host (cats, dogs, and various fish-eating mammals including humans) become infected by ingesting undercooked fish containing metacercariae.

After ingestion, the metacercariae excyst in the duodenum and migrate into the biliary ducts, where they attach and develop into adults, which lay eggs after 3 to 4 weeks

The adult flukes (O. viverrini: 5 mm to 10 mm by 1 mm to 2 mm; O. felineus: 7 mm to 12 mm by 2 mm to 3 mm) reside in the biliary and pancreatic ducts of the mammalian host, where they attach to the mucosa.

O. viverrini is found mainly in northeast Thailand, Laos, and Kampuchea. O. felineus is found mainly in Europe and Asia, including the former Soviet Union.

20 Petersen –Fasciolosis and opistorchiasis

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

Eggs in feces

Adult fluke

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

Most infections are asymptomatic.

In mild cases, manifestations include dyspepsia, abdominal pain, diarrhea or constipation.

Persistent infections may cause hepatomegaly and malnutrition.

In rare cases, cholangitis, cholecystitis, and chlolangiocarcinoma may develop.

Infections due to O. felineus may present an acute phase resembling Katayama fever (schistosomiasis), with fever, facial edema, lymphadenopathy, arthralgias, rash, and eosinophilia.

21 Petersen –Fasciolosis and opistorchiasis

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

Infection rates of mollusks and fishes with the larval stages of Trematoda of the family Opisthorchidae in the Yaroslavl Region

3,708 mollusks from the water reservoirs in the Yaroslavl Region were examined between to 1999.

Opisthorchis cercarias were found in 7 of the 10 studied water reservoirs. The total rate of infection of mollusks with all types with Trematoda partenitas and cercarias in different water reservoirs averaged 18% - 19% 19.1 It is concluded that there may be sporadic cases of Opisthorchis infection in wild and domestic animals and humans in the Yaroslavl Region.

Molodozhnikova et al. Med Parazitol (Mosk). 2006; Oct-Dec:34-7

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

22 Petersen –Fasciolosis and opistorchiasis

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

Treatment experience with biltricide in a natural focus of opisthorchiasis

A a total of 72 opisthorchiasis patients were treated with biltricide (praziquantel) 60 mg/kg body weight in a single dose.

Adverse reactions as giddiness were noted in 9 patients.

The efficiency of the therapy was monitored 3 months later, the control analysis detected no Opisthorchis eggs in 96% of the patients.

Guzeeva et al. Med Parazitol (Mosk). 1994;Apr-Jun:53

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

Fasciola hepatica

Niger river, Mali

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

23 Petersen –Fasciolosis and opistorchiasis

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

Eggs

Adult fluke

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

Carrada-Bravo and Escamilla Martínez Rev Mex Patol Clin, 2005;52:83-96

24 Petersen –Fasciolosis and opistorchiasis

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

France Prevalences of 0.34 to 3.1/100 000 are reported in Basse-Normandie; 0.83 to 1.16/100 000 in Corsica. Recent rates of approximately 0.03/100 000 per year are reported.

Portugal The prevalence was 2.0% in Fafe and 7.35% in Vizela during 1970 to 1972; 3.2% in the inner Porto region during the 1980's. 561 cases were

diagnosed in Porto National Laboratory during 1970 to 1985. 538 cases were reported in the literature during 1969 to 1989.

Gideon (http://www.gideononline.com/) reported in ProMED

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

Fascioliasis is found in most parts of the word and has appeared in outbreaks in Europe, especially in France and, particularly following wet summers.

The human infection has been reported from 42 countries in the last 2 decades with some in the form of outbreaks.

In South America, it occurs in areas of Cuba, Peru and Chile In Puerto Rico, the prevalence of fascioliasis is rising among cattle.

Recent outbreak of the infection has occurred in northern part of Iran(Pourtaghva, et al, 1989).

Weather has a marked effect on transmission and eggs passed through feces do not develop below 10C. Much watercress also dies down in the cold winter, although some metacercariae will survive over winter.

Adopted from the CDC (http://www.cdc.gov/ncidod/dpd/)

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

After ingestion, the metacercariae excyst in the duodenum and migrate

through the intestinal wall, the peritoneal cavity, and the liver parenchyma

into the biliary ducts, where they develop into adults.

In humans, maturation from metacercariae into adult flukes takes

approximately 3 to 4 months.

The adult flukes (Fasciola hepatica: up to 30 mm by 13 mm; F. gigantica: up

to 75 mm) reside in the large biliary ducts.

25 Petersen –Fasciolosis and opistorchiasis

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009 Carrada-Bravo and Escamilla Martínez Rev Mex Patol Clin, 2005;52:83-96

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

The acute phase caused by the migration of the immature fluke through the

hepatic parenchyma can last for months.

Symptoms include abdominal pain, hepatomegaly, fever, vomiting, diarrhea,

urticaria and eosinophilia.

In the chronic phase where the adult fluke is found within the bile ducts, the

symptoms reflect intermittent biliary obstruction and inflammation.

Occasionally, ectopic locations of infection (such as intestinal wall, lungs,

subcutaneous tissue, and pharyngeal mucosa) can occur.

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

Laboratory Diagnosis

Microscopic identification of eggs is useful in the chronic (adult) stage. Eggs can be recovered in the stools or in material obtained by duodenal or biliary drainage.

Antibody detection tests are useful especially in the early invasive stages, when the eggs are not yet apparent in the stools, or in ectopic fascioliasis.

The current tests of choice for immunodiagnosis of human Fasciola hepatica infection are enzyme immunoassays (EIA) with excretory-secretory (ES) antigens combined with confirmation of positives by immunoblot.

Hillyer GV. Parasitol al Dia 1993;17:130-6.

26 Petersen –Fasciolosis and opistorchiasis

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009

Triclabendazole (TCZ) is the treatment of choice for fascioliasis and is

effective at a single dose of 10 mg/kg body weight against the adult parasites

in the bile ducts and immature flukes migrating through the liver.

Triclabendazole is manufactured by Novartis and can be obtained for

isntance through the W.H.O. orphan drug programme.

WHO Informal Meeting on use of triclabendazole in fascioliasis control. 2006.

Emerging parasitic diseases –Opistorchis and Fasciola ECCMID Helsink i 2009 Thank you

Assekrem, Algiers

27 28 Summary

The changing epidemiology of Echinococcus multilocularis in Europe P. Deplazes (Zurich, CH)

Human alveolar echinococcosis (AE), a hepatic disease resembling cancer, is caused by the larval stage of the fox tapeworm Echinococcus multilocularis. In 1970, life expectancy for an average 54-year-old patient diagnosed with AE was estimated to be reduced by 18.2 and 21.3 years for men and women, respectively. However, by 2005, life expectancy of equally aged patients was reduced by only 3.5 and 2.6 years, respectively. The total median annual burden of the disease in Switzerland was €108,762 (€48,302-178,568) per patient (including medical costs, lost of income, but deducting saved pension costs due to premature mortality). The life-cycle of E. multilocularis in Europe predominantly involves foxes and rodents as definitive or intermediate hosts. Experimental studies in other potential definitive hosts revealed a comparable biotic potential of E. multilocularis in the dog and the raccoon dog whereas infections in cats resulted in low worm burdens with very few excreted eggs. In recent years, fox populations were growing in many European countries, and urban areas have been colonized. As a result, the E. multilocularis cycle is established in urban environments, and there is an increased infection risk for a large human population. Indeed, the incidence of AE per 100,000 significantly rose in Switzerland from approximately 0.10 cases between 1993 and 2000 to 0.26 cases between 2001 and 2005. Improved diagnostic accuracy, due to modern imaging techniques or advanced serology, was unlikely to account for this increase. The observed increase of human AE was some 10-15 years after the fox population started to rise in Switzerland which corresponds well to the latency period of AE. Ongoing changes in the epidemiology of AE are further documented by the emergence of human cases in the periphery of the well known “old” European endemic area, e.g. in the Baltic countries, in the last 15 years. For example, in a reference hospital for AE, the hospital of Tuberculosis and Infectious Diseases, Vilnius University in Lithuania, the registered AE cases/year increased form 0-4 in1997-2001 to 10-16 in 2002-2006. Studies in this country revealed high prevalence of E. multilocularis in foxes and raccoon dogs. However, whereas these data do not conclusively document an extension of the endemic area, they clearly demonstrate an increase of the infection pressure with eggs of this zoonotic parasite.

29 Deplazes –Multilocular echinococcosis

Alveolar Echinococcosis AE

Institute of Parasitology Toxocara University of Zurich Peter Deplazes

Approximative distribution of Echinococcus multilocularis in Central Europe

www.esccap.org

Echinococcus multilocularis: transmission biology

Definitive hosts: ecology, adult stage: susceptibility and development reproduction, survival

Egg: survival

metacestode: reproduction, survival

Intermediate host: ecology, susceptibility

30 Deplazes –Multilocular echinococcosis

Echinococcus multilocularis infection in the definitive host

• pathology and symptoms: hardly any! • cellular and humoral immunological reactions occur but protective mechanisms are not proven

foxes (n) biomass mean no. range total adults (65) 15%* 907 1 – 19,344 total subadults (68) 85%* 4 995 1 – 56,970 * significant differences in worm numbers (Mann-Whitney U-Test)

Echinococcus multilocularis: intestinal stage

1 mm

Estimates of the biotic potential from data in the literature: • prepatency 26-37days, • patency 2-3 months up to 1 year in low numbers • rate of proglottisation (very low) • mean number of eggs per proglottis: 200-300

E. multilocularis reproduction* in definitive hosts

Experimental raccoon infections (n=5) with cat dog fox 20 000 protoscolices dog

worm burden 35 dpi 642 2‘466 7‘930 16‘792

patency 75% (days) 10 24 19 13

patency 95% (days) 13 43 30 27

estimated total egg 573 279‘910 335‘361 346‘473 excretion*

egg production per established worms 0.9 114 42 21 (35 dpi)

* Maximum likelihood estimation Kapel et al., Inter J. Parasitol., 2006

31 Deplazes –Multilocular echinococcosis

Fox in the city of Zurich

Echinococcus multilocularis: Biology

Definitive host: fox

Intermediate host: voles

E. multilocularis detected (A) in fox faeces and (B) trapped voles (A. terrestris) in Zurich A B

E. multilocularis infected A. coproantigen positive terrestris 10 of 13 trapping areas coproantigen negative (prevalences: 4.3%-20.9%) Hofer et al. 2000, Parasitology

32 Deplazes –Multilocular echinococcosis

E. multilocularis egg contamination in the city of Zurich

Foxes infected with E. multilocularis Environmental contamination with at necropsy eggs?

60% 40% 19%

1 km

Factors affecting the urban cycle of E. multilocularis and the infection pressure with E. multilocularis eggs

forest agriculture & recreational area urban periphery central urban area

human population density and anthropogenic food supply

fox density

abundance of intermediate hosts

predation on rodents by foxes

environmental egg contamination

recreational and soil linked activities (farming, gardening, etc.)

free ranging dogs and cats increased risk for AE? -> evaluation of control strategy

Deplazes et al., Trends in Parasitology, 2004

33 Deplazes –Multilocular echinococcosis

Echinococcus: activation of the oncosphere

Echinococcus: early development of the oncosphere

activated oncosphere cyst development

laminated layer containing specific antigens

Proliferative growth of E. multilocularis metacestode in the liver

Eckert et al. 1985 Mehlhorn et al., 1985 Metacestode of E. multilocularis in the liver of a patient visualised with EmG11 mAb against Em2 antigen

34 Deplazes –Multilocular echinococcosis

E. multilocularis: Histology (HE-stain)

Aberrant host: typical alveolar structure mostly free of protoscolices

Intermediate host

Diagnosis of E. multilocularis metacestode infection in aberrant hosts - imaging techniques (US, CT) - serum antibody detection

- biopsy (not recommended)

- parasite structure, antigen, PCR after surgery

Organ: Liver in 97.5% of all cases involved

AE: organ localization

(data from 1993-2005, Switzerland, unpublished) • Involvement of one organ (80%) •Liver 97% •Lung 1% •Spleen 2% • Involvement of several organs (20%) • Liver 100% • Lung 27% • CNS 12% • Peritoneal space 23 %

•

35 Deplazes –Multilocular echinococcosis

Human Alveolar Echinococcosis

Active, progressive form of liver AE

Abortive form of AE

(courtesy of R. Rausch)

AE: Symptoms (Data from 1993-2005, Switzerland, unpublished) •Asymptomatic (26%) •Cardinal Symptoms •Right upper quadrant pain (37%) •Jaundice (12%) • Others (laboratory, neurologic, B-symptoms,… ) (27%)

PNM-System

• P= Hepatic localisation of Parasite • N=involvement of Neighbouring organs • M= distant Metastasis

Kern P, et. Al. WHO classification of alveolar echinococcosis: Principles and application. Parasitology International, Volume 55, Supplement 1, 2006, Pages S283-S287.

36 Deplazes –Multilocular echinococcosis

AE: Situation in Switzerland 1972-2005

4.0 PNM-Stage

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0.0

AE: Treatment

•Treatment of choice –radical resection followed by at least 2 years of antihelminthic treatment (Albendazole, Mebendazole) •Conservative treatment –Currently life-long treatment with antihelminthics (Albendazole, Mebendazole)

AE: Treatment in Switzerland (1970-2005)

Proportion of radical resections

100

40 Percentage

37 Deplazes –Multilocular echinococcosis

Statistical data: AE patient collective (n=112) from Switzerland

•Diagnosed 1993-2004: –Age at diagnosis: 54 y (SD 17.11), Min=12 y, Max=89 y –Female 67/112 (59.8%), Male 45/112 (40.2%) (p=0.037) –Mortality 3/112 (2.7%), none because of AE (3x carcinoma)

Improving life expectancy of female (solid line) and male (dotted line) AE patients in Switzerland compared to population norms (black). Normal- 35 female population 30 AE male 25

Life ex pectanc y at ag e 54 years Introduction of chemotherapy for treatment of AE 5

0 1970 1975 1980 1985 1990 1995 2000 2005 Yea r of diagnosis Torgerson et al. 2008, J. Hepatol.

Costs of AE in Switzerland (n = 155)

• Total median treatment cost of treatment per patient € 103,000 (CIs 90,000-118,000) • Loss of income € 78,500 (45,500-125,500) • Median cost per case pension deduced €182,500 (145,000-231,500), • Median cost per case pension costs deduced €108762 (€48300- €178,500) ) • Total cost in Switzerland €3.5 million (2.5-4.9 million)

Torgerson et al. 2008, J Hepatol.

38 Deplazes –Multilocular echinococcosis

Hypothesis:

Based on the significant increase of the infection pressure with E. multilocularis in rural and urban areas, an increase of the incidence of AE can be expected with a delay of 10-15 years!

Deplazes et al. 2004, Trends. Parasitol.

Retrospective study (50 years): 494 cases of Alveolar Echinococcosis in Switzerland

(Schweiger et al., unpublished)

Incidence of human AE in Switzerland 1956-2005 (cases per 100 000)

0.40 2.5

0.35 2 0.30

0.25 1.5 0.20 1 0.15

Incidence 0.10 0.5 Prevalence 0.05

0.00 0

urban rural 1970-1989 23% 77% 1990-2005 38% 62%

39 Deplazes –Multilocular echinococcosis

AE: a rare but emerging disease

0.30 60‘000 New cases (incidence) Forx population 0.25 50‘000

0.20 40‘000

~10 years 0.15 30‘000

0.10 20‘000 Fox population Fox population (statistics) 0.05 CH: 10-28 new cases per year 10‘000 Incidence / 100‘000 population & year population& 100‘000 / Incidence

0 0 45-49 50-54 56-60 61-65 66-70 71-75 76-80 81-85 86-90 91-95 96-00 01-05

Control of Alveolar Echinococcosis

• Elimination of definitive hosts (feasible only in small insular situations). • Intensive hunting within the border zone of the city of Zurich had no significant impact. • Praziquantel treatment of dogs and foxes in endemic situations