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Second WHO consultation: Development of a WHO reference panel for the control of Chagas diagnostic tests Geneva, 27 – 28 January 2009. Chagas disease in Spain: Experience from a reference laboratory. Teresa Gárate Servicio de Parasitología Centro Nacional de Microbiología.
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Second WHO consultation: Development of a WHO reference panel for the control of Chagas diagnostic tests Geneva, 27 – 28 January 2009 Chagas disease in Spain: Experience from a reference laboratory Teresa Gárate Servicio de Parasitología Centro Nacional de Microbiología
Experience from a Parasitology Reference Laboratory • General Role of the Parasitology Lab • Parasitology Lab and Chagas’ disease in Spain
Parasitic diseases • AUTOCTHONOUS • Leishmaniasis • Toxoplasmosis • Cryptosporidiasis • Giardiasis • Amebiasis • Fasciolosis • Hydatidosis • Anisakiasis • Toxocariosis • Trichinellosis • IMPORTED • Malaria • Other Leishmaniasis • Chagas disease • Sleeping sickness • Cysticercosis • Schistosomiasis • Filariasis/Oncho • Intestinal parasites National Microbiology Centre
The Parasitology Lab works with Spanish hospitals and blood donor centers on Chagas disease diagnosis
Other Activities related with T. cruzidiagnosis • Chagas Test evaluation • In house tests • Commercial tests • Control sample preparation • Serum of characterized patients • DNA from parasite strains • Blood spiked with parasites • Training microbiologists in • Microhaemotocrit • PCR • Serological result interpretation
PCR ELISA Commercial assays (rapid tests) Implementation of T. cruziDiagnostic Tools in Parasitology Lab Microscopic examination Xenodiagnosis IFAT Culture Real time PCR
Evaluation of serological tests: In house ELISAand 3 serum panels
Evaluation of serological tests: In house ELISAand 3 serum panels
Characteristics of serum samples of the 3 panels used in the evaluation of the In house ELISA Panel 1: Sera from Bolivian individuals with positive or negative xenodiagnosis Panel 2: Sera from population with positive or negative T. cruzi IFAT. Healthy individuals from endemic and non-endemic areas Panel 3: Sera of anti-T. cruzi Specific Panel and healthy individuals from endemic and non-endemic areas Anti-T. cruzi Specific Sera Panel (QPanel, Sao Paulo-Brazil, http://www.panel.com.br) was kindly provided by Dra. Elena Franco
Evaluation of serological tests: Commercial ELISAs
Characteristics of serum samples used in the evaluation of commercial tests
Evaluation of Commercial ELISAs: Specificity a The specificity was calculated into account results of healthy control b The specificity was calculated into account results of healthy control and other pathologies.
Molecular diagnosis of T. cruzi Control assay of limit detection Samples of population at-risk kDNA-PCRmodified (121-122 / HUF-REV) Brittoet al 1993; Cruz et al 2002; Walsh et al 1991; Dorn et al 1997; Gomes et al 1998; Wincker et al 1994; Rubio et al 2002
Molecular diagnosis of T. cruzi Diagnostic sensitivity and specificity
Chagas disease cases in Spain AUTOCTHONOUS IMPORTED • Blood transfusion • Congenital transmission • Organ transplant • Laboratory accidents • Immigration from endemic area • Long stays in endemic area
Latin American population in Spain On December 2008: > 1.8 million
Reports of TransfusionalChagas cases in Spain National Haemovigilance System
País Vasco A Coruña Madrid Characteristics of Infected donors: Malaga
Congenital Chagas disease Newborns examined during 2002 - 2008 Transmission index: ~ 4,5% * Post mortem diagnosis In Spain ≈ 990 000 women of childbearing age Bolivia: 132 421 women Argentina: 94 794 women
Laboratory Accidents and Chagas disease Alvar J. 1983 Laboratorio 76(456): 645-648
Chagas disease cases in Spain AUTOCTHONOUS IMPORTED • Blood transfusion • Congenital transmission • Organ transplant • Laboratory accidents • Immigration from endemic area • Long stays in endemic area
Chagas disease in blood donors at- risk Asturias Madrid
Profile of immigrant population Asturias 2006: ≈ 17 000 immigrant 2008: ≈ 20 000 immigrant Madrid 2006: ≈ 400 000 immigrant 2008: ≈ 500 000 immigrant
Prevalence in blood donors at-risk (2002-2006) ? P = Seropositive N = Seronegative
Seroprevalence in population at-risk: 24% ≈ 1144 Chagasic patients
Conclusions • Panel of Reference • - Positive samples by different serological tests, and • - Positive samples from chagasic individuals with parasitological, epidemiological and clinical evaluation. • Number of positive sera/panel • - 3 serum samples for kit manufacturers • - 100 serum samples for evaluation of tests • - 3 serum samples for quality control. • Chagas in Spain • - Imported and autochonous types. • - Bolivian group, mainly from Santa Cruz region, shows the highest seropositivity rates and represents the highest risk for T. cruzi infection transmission.
Thank you UNIDAD LEISHMANIA Y CHAGAS Carmen Cañavate Javier Nieto Mercedes Rodriguez Israel Cruz Elena Bodas Marta Hernández Rubén González Emilia García Carmen Chicharro María Flores
Chagas disease in Spain AUTOCTHONOUS IMPORTED Transfusional and congenital Chagas Immigration and long stays in endemic area Organ transplant and lab incident ? Months Years Chronic phase Acute
Level of anti-T. cruziIgG in samples of patients with positive PCR Acute case 1 (Madrid recipient) Acute case 2 (Málaga recipient)