Epidemiologia molecular de Giardia intestinalis em populações humanas e animais

Juares Elias Santos Junior

Resumo


Giardia intestinalis são parasitos protozoários intestinais, com distribuição cosmopolita, amplamente prevalente em humanos e em muitas espécies de mamíferos, incluindo animais domésticos e de produção. O objetivo desta revisão é sumarizar a pesquisa epidemiológica desta parasitose no mundo, com maior relevância para a América do Sul; particularmente no Brasil, enfatizando os principais genotipos encontrados em humanos, animais e meio ambiente, bem como a evolução e problemática das técnicas moleculares utilizadas na identificação dos genotipos descritos até o momento. Além disso, abordaremos questões sobre a correlação dos genotipos relacionados aos sinais clínicos e o atual significado zoonótico da giardíase.


Palavras-chave


Giardia intestinalis; prevalência; genótipos; zoonose; epidemiologia; Brasil

Texto completo:

PDF

Referências


Plutzer J, Ongerth J, Karanis, P. Review: Giardia taxonomy, phylogeny and epidemiology: Facts and open questions. Int J Hyg Environ Health. 2010;213:321-333.

Traub RJ, Monis P, Robertson I, Irwin P, Mencke N, Thompson RCA. Epidemiological and moleuclar evidence support the zoonótica transmission of Giardia among humans and dogs living in the same community. Parasitol. 2004; 128:53-62.

Sulaiman IM, Fayer R, Bern C, Gilman RH, Trout JM, Schantz PM, et al. Triosephosphate Isomerase Gene Characterization and Potential Zoonotic Transmission of Giardia duodenalis. Emerg Infec Dis. 2003;9(11):1444-1452.

Adams PJ, Monis PT, Elliot A.D, Thompson RCA. Cyst morfology and sequence analysis of the samll subunit rDNA and ef 1α identifies a novel Giardia genotype in a quenda (Isoodon obesulus) from Western Austrália. Infect Genetic Evolut. 2004;4 (4):365-370.

Paulina, R. C. Detecção molecular de Giardia sp em amostras fecais e água: extração de DNA genômico, PCR e RFLP. 107 f. Tese (Doutorado em Saúde Humana e Animal) - Curitiba (PR): Universidade Federal do Paraná, Setor de Tecnologia, 2005.

Feng Y, Xiao L. Zoonotic Potential and Molecular Epidemiology of Giardia Species and Giardiases. Rev Clin Microbiol. 2011;24(1):110-140.

Hung CC, Deng HY, Hsiao WH, Hsieh SM, Hsiao CF, Chen MY, et al. Invasive amebiasis as an emerging parasitic disease in patients with human immunodeficiency virus type 1 infection in Taiwan. Arch Int Med. 2006;165:409-415.

Souza MC, Morais, JB, Machado, JE, Poiares-Da-Silva, J. Genotyping of Giardia lamblia Human Isolates from Portugal by PCR-RFLP and Sequencing. J Eukaryot Microbiol. 2006 v. 53 (S1):S174-S176.

Graczyk TK, Grimes BH, Knight R, Da Silva, AJ, Pieniazek NJ, Veal. Detection of Cryptosporiduim parvum and Giardia lamblia carried by synanthropic flies by combined fluorescent in situ hybridization and a monoclonal antibody. Am J Trop Med Hyg. 2003; 68(2):228-232.

Wolfe MS. Giardiasis. Clin Microbiol Rev. 1992;5:93-100.

Homan W, Mank T. Human giardiasis: genotype linked differences in clinical symptomatology. Int J Parasitol. 2001;31:822-6.

Gennari SM, Souza S. Giardíase. São Paulo Fort Dodge Saúde Animal. 2002; p.13.

Adam, RD. Biology of Giardia lamblia. Clin Microbiol Rev. 2001;14:447-475.

Hanevik K, Hausken T, Morken MH, Strand EA, Mørch K, Coll P, et al. Persisting symptoms and duodenal inflammation related to Giardia duodenalis infection. J Infect. 2007;55:524-30.

Ankarklev J, Jerlström-Hultqvist J, Ringqvist E, Troell K, Svärd SG. Behind the smile: cell biology and disease mechanisms of Giardia species. Nat Rev Microbiol. 2010; 8:413-22.

Thompson, R. C. A., R. M. Hopkins, and W. L. Homan. Nomenclature and genetic groupings of Giardia infecting mammals. Parasitol Today. 2000;16: 210-213.

Carvalho KPC, Monteiro-Leal L H. The effects of metronidazole end furazolidone during Giardia differentiation into cysts. Exp Parasitol, 2004;113(3):135-141.

Frasson AP, Vieira, PB, De Carli, GA, Tasca, T. Giardia lamblia: Distribuição de microtúbulos no citoesqueleto de trofozoítos e cistos utilizando taxóide fluorescente.Rev Patolog Trop. 2010;39(1):21-32.

WHO/CDS/IPI/92.2. WHO/PAHO informal consultation on intestinal protozoal infections, México, October 1991.

Marshall MM, Naumovitz D, Ortega Y, Sterling CR. Waterborne protozoan pathogens. Clin Microbiol Rev, v. 10, p. 67-85, 1997. Erratum in: Clin. Microbiol Rev. 1997; 11: 404-1997.

Instituto Brasileiro de Geografia e Estatística. http://www.ibge.gov.br/ibgeteen/pesquisas/fecundidade.html Acessado dia 5 de agosto de 2011.

Cardoso GS, Santana ADC, Aguiar CP. Frequência e aspectos epidemiológicos da giardíase em creches do município de Aracaju, SE, Brasil. Rev Soc Bras Med Trop. 1995;28(10):25-31.

Escobedo A. A, Almirall P, Robertson LJ, Franco RM, Hanevik K, Mørch K, et al. Giardiasis: the ever-present threat of a neglected disease. Infect Disord Drug Targets. 2010;10(5):329-48.

Zaiden M. F. Enteroparasitoses em crianças de 0 a 6 anos de creches municipais de Rio Verde-GO e sua interface com o meio ambiente. [dissertação]. Franca: SP. Universidade de Franca, Promoção da saúde, 2006.

Schnack FJ, Fontana LM, Barbosa PR, Silva LSM, Baillargeon CMM, Barichello T, et al. Enteropatógenos associados com diarréia infantil ( < 5 anos de idade) em amostra da população da área metropolitana de Criciúma, Santa Catarina, Brasil. Cad Saúde Pub. 2003;19:1205-208.

Machado RLD, Figueredo MC, Frade AF, Kudó ME, Silva FMG, Povoa MM. Comparação de quatro métodos laboratoriais para diagnóstico da Giardia lamblia em fezes de crianças residentes em Belém, Pará. Rev Soc Bras Med Trop. 2001; 34: 91-3.

Menezes AL, Lima VM, Freitas MT, Rocha MO, Silva EF, Dolabella SS. Prevalence of intestinal parasites in children from public daycare centers in the city of Belo Horizonte, Minas Gerais, Brazil. Rev Inst Med Trop. 2008;50(1):57-9.

Carvalho, T. B.; De Carvalho, L. R.; Mascarini, L. M.. Ocurrence of enteroparasitoses in day care centers in Botucatu (Sao Paulo State, Brazil) with emphasis on Cryptosporiduim spp., Giardia duodenalis and Enterobius vermicularis, Rev Int. Med. Trop. 2006;48:269-273.

Tashima NT, Simões MJS. Parasitas intestinais; prevalência e correlação com a idade e com os sintomas apresentados de uma população infantil de Presidente Prudente – SP. Rev Bras Anal Clin. 2005;37(1):35-39.

Lopéz FRD, Montero M, Gonzalez JD, Alvarez MAG. Factores de riesgo de giardiasis em ninõs de 0 a 6 anos. Rev Cubana Med Gen Integr. 1997;13(3):227-31

Costa-Macedo LM, Rey L. Aleitamento e parasitismo intestinal materno-infantil. Rev Soc Bras Med Trop. 2000;33(4):371-375.

Machado RC, Marcari EL, Cristante S, Crisante V, Carareto CM. Giardíase e helmintíases em crianças de creches e escolas de 1° e 2° graus (públicas e privadas) da cidade de Mirassol (SP, Brasil). Rev Soc Bras Med Trop. 1999; 32(6):697-704.

Buyukbaba BO, Uysal H, Alan S, Nazlican O. Investigation of intestinal parasites in AIDS patients. Microbiol Bul. 2004;38:121-128.

Ramakrishnan K, Shenbagarathai R, Uma A, Kavitha K, Rajendran R, Thirumalaikolundusubramanian P. Prevalence of intestinal parasitic infestation in HIV/AIDS patients with diarrhea in Madurai City, South India. Jpn J Infect Dis. 2007; 60:209-210.

Moura H, Fernandes O, Viola JPB, Silva SP, Passos RH, Lima DB. Enteric parasites and HIV infection: occurrence in AIDS patients in Rio de Janeiro, Brazil. Mem Inst Oswaldo Cruz. 1989; 84:527-533.

Gonçalves AC, Gabbay YB, Mascarenhas JD, Yassaka MB, Moran LC, Fraga VD, et al. Calicivirus and Giardia lamblia are associated with diarrhea in human immunodeficiency virus-seropositive patients from southeast Brazil. Am J Trop Med Hyg. 2009;81:463-6.

Rossit AR, Almeida MT, Nogueira CA, Costa Oliveira JG, Barbosa DM, Moscardini AC, et al. Bacterial, yeast, parasitic, and viral enteropathogens in HIV-infected children from São Paulo State, Southeastern Brazil. Diagn Microbiol Infect Dis. 2007;57:59-66.

Silva RR, da Silva CAM, Pereira CAJ, Nicolato RLC, Negrão-Correa D, Lamounier JA, et al. Association between nutritional status, environmental and socio-economic factors and Giardia lamblia infections among childrem aged 6-71 months in Brazil. Trans. R. Soc. Trop. Med. Hyg. 2009,103 (5):512-519.

Ng CT, Gilchrist CA, Lane A, Roy S, Haque R, Houpt R. Multiples Real-Time PCR Assay Using Scorpion Probes and DNA Capture for Genotype-Specific Detection of Giardia lamblia on Fecal Samples. J. Clin. Microbiol. 2005;43(3):1256-1260.

Cacciò SM, Beck R, Lalle M, Marinculic A, Pozio E. Multilocus genotyping of Giardia duodenalis reveals striking differences between assemblages A e B. Int J Parasitol. 2008; 38:1523-1531

Lee Jh, Lee J, Park Sj, Yong Ts, Hwang UW. Detection and genotyping of Giardia intestinalis isolates using intergenic spacer (IGS)-based PCR. Kor J Parasitol. 2006; 44( 4): 343-353.

Bertrand I, Albertini L, Schwartzbrod J. Comparison of Two Target Genes for Detection and Genotyping of Giardia lamblia in Human Feces by PCR and PCR - Restricition Fragment Length Polymorphism. J. Clin. Microbiol. 2005; 43(12):5940-5944.

Souza SLP, Gennari SM, Richtzenhain LJ, Pena HFJ, Funada MR, Cortez A, et al. Molecular identification of Giardia duodenalis isolates from humans, dogs, cats and cattle from the state of São Paulo, Brazil, by sequence analysis of fragments of glutamate dehydrogenase (gdh) coding gene. Vet Parasitol. 2007;149:258-264.

Ey P, Mansouri M, Kulda J, Nohynkova E, Monis P, Andrews R, et al. Genetic analisys of Giardia from hoofed farm animal reveals artiocadactyl-specific and potentially zoonotic genotypes. J Eukaryot Microbiol, 1997;44:626-635.

Hopkins RM, Meloni BP, Groth DM, Wetherall JD, Reynoldson JA, Thompson C A. Ribosomal RNA sequencing reveals differences between the genotypes of Giardia isolates recovered from humans and dogs living in the same locality. J Parasitol. 1997;83:44-51.

Abe N, Kimata I, Tokoro M. Genotyping of Giardia Isolates From Humans on Japan Using the Small Subunit Ribosomal RNA and Glutamate Dehydrogenase Sequences. Jpn J Infect Dis. 2005;58: 57-58.

Palmer CS, Traub RJ, Robertson ID, Devlin G, Rees R, Thompson RCA. Determining the zoonotic significance of Giardia and Cryptosporiduim in Australian dogs and cats. Vet Parasitol. 2008;154:142-147.

Read CM, Monis PT, Thompson RC. Discrimination of all genotypes of Giardia duodenalis at the glutamate dehydrogenase locus using PCR-RFLP. Infec Genet Evol. 2004;4:125-130.

Traub RJ, Inpankaew T, Reid SA, Sutthikornchai C, Sukthana Y, Robertson LD, et al. Transmission cycles of Giardia duodenalis in dogs and humans in temple communities in Bangkok-a critical evaluation of its prevalence uding three diagnostic tests in the Field in the absence of a gold standard. Acta Trop. 2009;111:125-132.

Sprong H, Cacciò SM, van der Giessen JWB, on behalf of the ZOOPNET network and partners. Identification of Zoonotic Genotypes of Giardia duodenalis. PLos Negl Trop Dis. 2009;3(12): e558.

Langkjaer RB, Vigre H, Enemark HL, Maddox-Hytel C. Molecular and phylogenetic characterization of Cryptosporiduim and Giardia from pigs and cattle in Denmark. Parasitol. 2007; 134:339-350.

Foronda P, Bargues MD, Abreu-Acosta N, Periago MV, Valero MA, Valladares B, et al. Identification of Genotypes of Giardia intestinalis of Human Isolates in Egypt. 2008. Parasitol Res 103:1177-1181.

Lebbad M, Mattsson JG, Christenson B, Ljungström B, Backhans A, Anderson JO. From mouse to mouse: Multilocus genotyping of Giardia isolates from various animal species. Vet Parasitol. 2010;168:231-239.

Armson A, Yang R, Thompson J, Johnson J, Reid S, Ryan UM. Giardia genotypes in pigs in Western Australia: prevalence and association with diarrhea. Exp Parasitol. 2009; 121:381-383.

Gelanew T, Lalle M, Hailu A, Pozio E, Cacciò SM. Molecular characterization of human isolates of Giardia duodenalis from Etiópia. Acta Trop. 2007;102: 92-99.

Gaydos JK, Miller WA, Kreuder-Johnson C, Zornetzer H, Melli AC, Pachhan AE, et al. Novel and canine genotypes of Giardia duodenalis in harbor seals (Phoca vitulina richardsi). J Parasitol. 2008; 94:1264-1268.

Lasek-Nesselquist E, Welch DM, Sogin ML. The identification of a new Giardia duodenalis assemblage in marine vertebrates and a preliminary analysis of G. duodenalis population biology in marine systems. Int J Parasitol. 2010; 40:1063-1074.

Franzen O, Jerlstrom-Hultqvist J, Castro E, Sherwood E, Ankarklev J, Reiner DS, et al. Draft genome squencing of Giardia intestinalis assemblage B isolate GS: is human giardiasis caused by two different species? PLos Pathog. 2009;5: e1000560.

Matsubayashi M, Kimata I, Abe N. Identification of Genotypes of Giardia intestinalis from a Human and Calf in Japan. 2005. J Vet Med Sci. 67 (3):337-340.

Fallah E, Nahavandi KH, Jamali R, Poor BM, Asgharzadeh M, J. Molecular Identification of Giardia duodenalis Isolates from Human and Animal Reservoirs by PCR-RFLP Biol Sci. 2008;1-6.

Winkworth CL, Learmonth JJ, Matthaei CD, Townsend CR. Molecular Characterizatiion of Giardia isolates from calves and humans in a Region in which Dairy Farming hás Recently Intensified. Appl environ microbiol. 2008;74(16):5100-5105.

Eligio-García L, Cortes-Campos A, Jimenez-Cardoso E. Geno¬type of Giardia intestinalis isolates from children and dogs and its relationship to host origin. Parasitol Res. 2005;97:1-6.

Robertson LJ, Hermansen L, Gjerde BK. Occurrence of Cryptosporiduim Oocysts and Giardia Cysts in Sewage in Norway. Appl Enviroment Microbiol. 2006;72 (8): 5297-5303.

Van der Giessen JWB, de Vries A, Roos M, Wielinga P, Kortbeek LM, Mank TG. Genotyping of Giardia in Duth patients and animals: A phylogenetic analysis of human and animal isolates. Int J for Parasitol. 2006;36:849-858.

Robertson LJ, Forberg T, Hermansen L, Gjerde BK, Langeland N. Molecular characterisation of Giardia isolates from clinical infections following a waterborne outbreak. J Infec. 2007;55:79-88.

Khan, S.M., Debnath C, Pramanik AK, Xiao L, Nozak T. Ganguly S. Molecular evidence for zoonotic transmission of Giardia duodenalis among dairy farm workers in West Bengal, Índia. Vet Parasitol. 2011;178(3-4):342-345.

Johnston AR, Gillespie TR, Rwego IB, Mclachlan TLT, Kent AD, Goldberg TL. Molecular Epidemiolgy of Cross-Species Giardia duodenalis Transmission in Western Uganda. PLoS Negl Trop Dis. 2010;4(5):e 683.

Marangi M, Berrilli F, Otranto D, Giangaspero A. Genotyping of Giardia duodenalis Among Children and Dogs in a Closed Socially Deprived Community From Italy. Zoonoses Public Health. 2010;57:54-58.

Lalle M, Pozio E, Capelli G, Bruschi F, Crotti D, Cacciò SM. Genetic heteregeneity at the β-giardin lócus among human and animal osolates of Giardia duodenalis and identification of potentially zoonotic subgenotypes. Int J Parasitol. 2005;35:207-213.

Minvielle MC, Molina NB, Polverino D, Basualdo JA. First genotyping of Giardia lamblia from human and animal feces in Argentina, South América. Mem Inst Oswaldo Cruz. 2008;103(1):98-103.

Cooper MA, Sterling CR, Gilaman RH, Cama V, Ortega Y, Adam RD. Molecular analysis of household transmission of Hight endemicity in Peru. J Infec Dis. , 2010; 202:1713-1721.

Kutz S, Thompson RCA, Polley L, Kandola K, Nagy J, Wielinga CM, et al. Giardia assemblage A: human genotype in muskoxen in the Canadian Artic. Paras Vec. 2008; 1:32.

Yang R, Reid A, Lymbery A, Ryan U. Identification of Zoonotic Giardia Genotypes in Fish. Int J Parasitol. 2010;40:779-785.

Trout JM, Santín M, Fayer R. Detection of Assemblage A, Giardia duodenalis and Emeria spp. in Alpacas on two Maryland farms. Vet Parasitol. 2008;153:203-208.

Lobo ML, Xiao L, Antunes F, Matos O. Ocurrence of Cryptosporiduim and Giardia genotypes and subtypes in raw and treated water in Portugal. Let Appl Microbiol. 2009; 48:732-737.

Baque RH, Gilliam AO, Robles LD, Jakubowski W, Slifko TR. A real-time RT-PCR method to detect viable Giardia lamblia cysts in enviromental waters. Water Res.2011;45:3175-3184.

Ruiz A, Foronda P, Gonzáles JF, Guedes A, Abreu-Acosta N, Molina JM, et al. Occurrence and Genotype Characterization of Giardia duodenalis in Goat Kids from the Canary Islands, Spain. Vet Parasitol. 2008; 154:157-141.

Appelbee A. J. Prevalence and genotyping of Giardia duodenalis from beef calves in Alberta, Canada. Vet. Parasitol. 2003;122:289-29468.

Itoh N, Itagaki T, Kawabata T, Konaka T, MuraoKa N, Saeki H, et al. Prevalence of intestinal parasites and genotyping of Giardia intestinalis in pet shop puppies in east Japan. Vet Parasitol. 2011;176:74-78.

Lim YAL, Ramasame SD, Mahdy MAK, Sulaiman WYW, Smith HV. Detection and molecular characterization of Giardia isolated from recreacional lake water in Malaysia. Parasitol Res. 2009;106(1):289-291.

Almeida A, Moreira MJ, Soares S, Delgado ML, Figueiredo J, Silva E, et al. Biological and genetic characterization of Cryptosporidium ssp. and Giardia duodenalis isolates from five hydrographical basins in Northern Portugal. Korean J Parasitol. 2010; 48(2):105-111.

Bertrand I, Schwartzbrod J. Detection and genotyping of Giardia duodenalis in wasterwater: Relation between assemblages and faecal contamination origin. Water Res. 2007;41:3675-3682.

Mundim MJS, Rosa LAG, Hortêncio SM, Faria ESM, Rodrigues RM, Cury MC. Prevalence de Giardia duodenalis and Cryptosporidium spp. in dogs from different living conditions in Uberlândia, Brazil. Vet Parasitol. 2007; 44: 356-359.

Santos RCV, Hoerlle JL, Aquino ARC, De Carli GA. Prevalência de enteroparasitoses em pacientes ambulatoriais do Hospital Divina Providência de Porto Alegre, RS. Rev Bras Anal Clin;2004;36(4):241-243.

Volotão AC, Costa-Macedo L.M, Haddad FSM, Brandão A, Peralta J.M, Fernandes O. Genotyping of Giardia duodenalis from human and animal samples from Brazil using β-giardin gene: A phylogenetic analysis. Acta Trop. 2007;102:10-19.

Rocha MO, Gomes MA, Costa AO, Furst C, Silva E F. Molecular characterization of Brazilian human Giardia duodenalis isolates using isoenzyme and randon amplified polymorphic DNA analysis. Diag Microbiol Infect Dis. 2003;46:273-278.

Volotão AC, Júnior Souza JC, Grassini C, Peralta JM, Fernandes O. Genotyping of Giardia duodenalis from Southern Brown Howler Monkeys (Alouatta clamitans) from Brazil. Vet. Parasitol. 200;158(1-2):133-137

Volotão AC, Ramos NMD, Fantinatti M, de Moraes MVP, Storti-Melo LM, de Godoy EAM, et al. Giardiasis as zoonosis: between proof of priciple and paradigm in the Northwestern region of São Paulo State, Brazil. Braz Infect Dis. 2011;15(4):382-383.

Gomes KB, Fernandes AP, Menezes A, Júnior RA, Silva EF, Rocha MO. Giardia duodenalis: genotypic comparison between a human and a canine isolates. Rev Soc Bras Med Trop. 2011;44(4):508-510.

Soares RM, Souza SLP, Silveira LH, Funada MR, Richtzenhain LJ, Gennari SM. Genotyping of potentially zoonotic Giardia duodenalis from exotic and wild animals Kept in captivity in Brazil. Vet Patasitol. 2011;180:344-348.

Paz e Silva F, Monobe MM, Lopes R, Araujo Jr JP. Molecular characterization of Giardia duodenalis in dogs from Brazil. Parasitol Res. In Press 2011.

Tashima NT, Simões MJS., Leite CQF, Fluminhan A, Nogueira MA, Malaspina AC. Classic And Molecular Study Of Giardia Duodenalis In Children From A Daycare Center In The Region Of Presidente Prudente, São Paulo, Brazil. Rev Inst Med Trop. 2009;51(1):19-24.

Fernandes LN, Souza PP, Araújo RN, Razzolini MTP, Soares RM, Sato MIZ, et al. Detection of assemblages A e B of Giardia duodenalis in water and sewage from São Paulo state, Brazil. J Water Health. 2011;09(2):361-67.

Kohli A, Bushen OU, Pinkerton RC, Houpt E, Newman RD, Sears CL, et al. Giardia duodenalis assemblage, clinical presentation and markers of intestinal inflammation in Brazilian Children. Trans R Soc Trop Med Hyg. 2008;102:718-725.

Morrison HG, McArthur AG, Gillin FD, Aley SB, Adam RD, Olsen GJ, et al. Genomic Minimallism in the Early Diverging Intestinal Parasite Giardia lamblia. Science, 2007; 317:1921-1926.

Mahdy AKM, Surin J, Wan K.L, Mohd-Adnan A, Al-Mekhlafi MSH, Lim YAL. Giardia intestinalis genotypes: Risk factors and correltion with clinical symptoms. Acta trop. 2009;112:67-70.

Read C, Walters J, Robertson ID, Thompson RC. Correlation between genotype of Giardia duodenalis and diarreia. Int. J. Parasitol. 2002;32:229-231.

Paintlia AS, Descoteaux S, Spencer B, Chakraborti A, Ganguly NK, Mahajan RC, et al. Giardia lamblia groups A and B among young adults in Índia. Clin Infect Dis. 1998;26:190-191.

Ajjaampur SSR, Sankaran P, Kannan A, Sathyakumar K, Sarkar R, Gladstone BP, Kang G. Giardia duodenalis assemblages associated with diarrhea in children in South Índia identified by PCR-RFLP. Am J Trop Med Hyg. 2009;80(1):16-19.

Aydin AF, Besirbellioglu BA, Tanyuksel M, Araz E, Pahsa A. Classification of Giardia duodenalis parasites in Turkey into groups A and B using restriction fragment lenght polymorphism. Diag Microbiol Infect Dis. 2004;50:147-151.

Pelayo L, Nuñez FA, Rojas L, Furuseth Hansen E, Gjerde B, Wilke H, Mulder B,

Robertson L. Giardia infections in Cuban children: the genotypes circulating in a rural population. 2008 Ann. Trop. Med. Parasitol. 102, (7) 585-595

102- Breathnach AS, Mchugh TD, Butcher PD. Prevalence and clinical correlations of gnetic subtypes of Giardia lamblia in an urban setting. Epidemiol Infect. 2010;138: 1459-1467.

Robertson LJ, Hanevik K, Escobedo AA, Mørch K, Langeland N. Giardiasis – Why do the symptoms sometimes never stop? Trends parasitol. 2010; 26 (2),75-82.

Cacciò SM, Sprong H. Giardia duodenalis recombination and its implications for taxonomy and molecular epideliology. Exp Parasitol. 2010;124:107-112.

Cacciò SM, Beck R, Lalle M, Marinculic A, Pozio E. Multilocus genotyping of Giardia duodenalis reveals striking differences between assemblages A e B. Int J Parasitol. 2008;38:1523-1531.