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Praziquantel: its use in control of schistosomiasis in sub-Saharan Africa and current research needs

Published online by Cambridge University Press:  13 March 2009

M. J. DOENHOFF*
Affiliation:
School of Biology, University of Nottingham, University Park, NottinghamNG7 2RD, UK
P. HAGAN
Affiliation:
Faculty of Biomedical and Life Sciences, Division of Infection and Immunity, University of Glasgow, Scotland, G12 8QQ, UK
D. CIOLI
Affiliation:
Institute of Cell Biology, 32 Via Ramarini, 00015 Monterotondo, Rome, Italy
V. SOUTHGATE
Affiliation:
Parasitology Division, Wolfson Wellcome Biomedical Laboratories, Natural History Museum, Cromwell Road, South Kensington, LondonSW7 5BD, UK
L. PICA-MATTOCCIA
Affiliation:
Institute of Cell Biology, 32 Via Ramarini, 00015 Monterotondo, Rome, Italy
S. BOTROS
Affiliation:
Theodor Bilharz Research Institute, Warrak El-Hadar Imbaba, P.O. Box 30, Imbaba, Giza, 12411Egypt
G. COLES
Affiliation:
Department of Clinical Veterinary Science, University of Bristol, Langford House, Langford, BristolBS40 5DU, UK
L. A. TCHUEM TCHUENTÉ
Affiliation:
Centre for Schistosomiasis and Parasitology, University of Yaoundé I, P.O. Box 7244, Yaoundé, Cameroon
A. MBAYE
Affiliation:
Institut Médecine Tropicale Appliquée, University of Dakar, B.P. 11294, Dakar Peytavin, Senegal
D. ENGELS
Affiliation:
World Health Organization, Department of Neglected Tropical Diseases, Preventive Chemotherapy and Transmission Control, 20 Avenue Appia, CH-1211 Geneva 27, Switzerland
*
*Corresponding author: Michael J. Doenhoff, School of Biology, University of Nottingham, University Park, NottinghamNG7 2RD, UK. Tel: +44 1115 951-3304; Fax: +44 115 951-3251; E-mail: mike.doenhoff@nottingham.ac.uk

Summary

Treatment with praziquantel (PZQ) has become virtually the sole basis of schistosomiasis control in sub-Saharan Africa and elsewhere, and the drug is reviewed here in the context of the increasing rate that it is being used for this purpose. Attention is drawn to our relative lack of knowledge about the mechanisms of action of PZQ at the molecular level, the need for more work to be done on schistosome isolates that have been collected recently from endemic areas rather than those maintained in laboratory conditions for long periods, and our reliance for experimental work mainly on Schistosoma mansoni, little work having been done on S. haematobium. There is no evidence that resistance to PZQ has been induced in African schistosomes as a result of its large-scale use on that continent to date, but there is also no assurance that PZQ and/or schistosomes are in any way unique and that resistant organisms will not be selected as a result of widespread drug usage. The failure of PZQ to produce complete cures in populations given a routine treatment should therefore solicit considerable concern. With few alternatives to PZQ currently available and/or on the horizon, methods to monitor drug-susceptibility in African schistosomes need to be devised and used to help ensure that this drug remains effective for as long a time as possible.

Type
SECTION 5 TOWARDS FUTURE USE OF PRAZIQUANTEL
Copyright
Copyright © 2009 Cambridge University Press

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References

REFERENCES

Abdulla, M. H., Lim, K. C., Sajid, M., Mckerrow, J. H. and Caffrey, C. R. (2007). Schistosomiasis mansoni: novel chemotherapy using a cysteine protease inhibitor. PLoS Medicine 4, e14.CrossRefGoogle ScholarPubMed
Allen, H. E., Crompton, D. W. T., de Silva, N., LoVerde, P. T. and Olds, G. R. (2002). New policies for using anthelmintics in high risk groups. Trends in Parasitology 18, 381382.CrossRefGoogle Scholar
Alonso, D., Munoz, J., Gascon, J., Valls, M. E. and Corachan, M. (2006). Failure of standard treatment with praziquantel in two returned travelers with Schistosoma haematobium infection. American Journal of Tropical Medicine and Hygiene 74, 342344.CrossRefGoogle Scholar
Appleton, C. C. and Mbaye, A. (2001). Praziquantel–quality, dosages and markers of resistance. Trends in Parasitology 17, 356357.CrossRefGoogle ScholarPubMed
Araujo, N., Katz, N., Pinto Dias, E. and De Souza, C. P. (1980). Susceptibility to chemotherapeutic agents of strains of Schistosoma mansoni isolated from treated and untreated patients. American Journal of Tropical Medicine and Hygiene 29, 890894.CrossRefGoogle ScholarPubMed
Baard, A. P., Sommers, D. K., Honiball, P. J., Fourie, E. D. and Du Toit, L. E. (1979). Preliminary results in human schistosomiasis with Ro 11-3128. South African Medical Journal 55, 617618.Google ScholarPubMed
Badria, F., Abou-Mohamed, G., El-Mowafy, A., Masoud, A. and Salama, O. (2001). Mirazid: a new schistosomicidal drug. Pharmaceutical Biology 39, 127131.CrossRefGoogle Scholar
Barakat, R., Elmorshedy, H. and Fenwick, A. (2005). Efficacy of myrrh in the treatment of human schistosomiasis mansoni. American Journal of Tropical Medicine and Hygiene 73, 365367.CrossRefGoogle ScholarPubMed
Barduagni, P., Hassanein, Y., Mohamed, M., El Wakeel, A., El Sayed, M., Hallaj, Z. and Curtale, F. (2008). Use of triclabendazole for treatment of patients co-infected by Fasciola spp. and S. mansoni in Behera Governate, Egypt. Parasitology Research 102, 631633.CrossRefGoogle Scholar
Booth, M., Vounatsou, P., N'Goran, E. K., Tanner, M. and Utzinger, J. (2003). The influence of sampling effort and the performance of the Kato-Katz technique in diagnosing Schistosoma mansoni and hookworm co-infections in rural Côte d'Ivoire. Parasitology 127, 525531.CrossRefGoogle ScholarPubMed
Botros, S. and Bennett, J. L. (2007). Praziquantel resistance. Expert Opinion on Drug Discovery 2, 535540.CrossRefGoogle ScholarPubMed
Botros, S. S., Hammmam, O. A., El-Lakhany, S. H., Seif el-Din, S. H. and Ebeid, F. A. (2008). Schistosoma haematobium (Egyptian strain): rate of development and effect of praziquantel treatment. Journal of Parasitology 94, 386394.CrossRefGoogle ScholarPubMed
Botros, S., Pica-Mattoccia, L., William, S., El-Lakkani, N. and Cioli, D. (2005 a). Effect of praziquantel on the immature stages of Schistosoma haematobium. International Journal for Parasitology 35, 14531457.CrossRefGoogle ScholarPubMed
Botros, S., Sayed, H., Amer, N., El-Ghannam, M., Bennett, J. L. and Day, T. A. (2005 b). Current status of sensitivity to praziquantel in a focus of potential drug resistance in Egypt. International Journal for Parasitology 35, 787791.CrossRefGoogle Scholar
Botros, S., Sayed, H., El-Dusoki, H., Sabry, H., Rabie, I., El-Ghannam, M., Hassanein, M., El-Wahab, Y. A. and Engels, D. (2005 c). Efficacy of mirazid in comparison with praziquantel in Egyptian Schistosoma mansoni-infected school children and households. American Journal of Tropical Medicine and Hygiene 72, 119123.CrossRefGoogle ScholarPubMed
Botros, S., William, S., Ebeid, F., Cioli, D., Katz, N., Day, T. A. and Bennett, J. L. (2004). Lack of evidence for an antischistosomal activity of myrrh in experimental animals. American Journal of Tropical Medicine and Hygiene 71, 206210.CrossRefGoogle ScholarPubMed
Brady, M. A., Hooper, P. J. and Ottesen, E. A. (2006). Projected benefits from integrating NTD programs in sub-Saharan Africa. Trends in Parasitology 22, 285291.CrossRefGoogle ScholarPubMed
Brooker, S., Kabatareine, N. B., Gyapong, J. O., Stothard, J. R. and Utzinger, J. (2009). Rapid assessment of schistosomiasis and other neglected tropical diseases in the context of integrated control programmes in Africa. Parasitology 136 (In Press).CrossRefGoogle ScholarPubMed
Cioli, D., Botros, S. S., Wheatcroft-Francklow, K., Mbaye, A., Southgate, V., Tchuem Tchuenté, L. A., Pica-Mattoccia, L., Troiani, A. R., El-Din, S. H., Sabra, A. N., Albin, J., Engels, D. and Doenhoff, M. J. (2004). Determination of ED50 values for praziquantel in praziquantel-resistant and -susceptible Schistosoma mansoni isolates. International Journal for Parasitology 34, 979987.CrossRefGoogle ScholarPubMed
Cioli, D. and Pica-Mattoccia, L. (2003). Praziquantel. Parasitology Research 90, S39.CrossRefGoogle ScholarPubMed
Cioli, D., Pica-Mattoccia, L. and Archer, S. (1995). Antischistosomal drugs: past, present … and future? Pharmacology and Therapeutics 68, 3585.CrossRefGoogle ScholarPubMed
Cioli, D., Valle, C., Angelucci, F. and Miele, A. (2008). Will new antischistosomal drugs finally emerge? Trends in Parasitology 24, 379382.CrossRefGoogle ScholarPubMed
Coles, G. C. (1971). Alteration of Schistosoma mansoni malate dehydrogenase isoenzymes on passage in the laboratory. Comparative Biochemistry and Physiology B 40, 10791083.CrossRefGoogle ScholarPubMed
Coles, G. C., Mutahi, W. T., Kinoti, G. K., Bruce, J. I. and Katz, N. (1987). Tolerance of Kenyan Schistosoma mansoni to oxamniquine. Transactions of the Royal Society of Tropical Medicine and Hygiene 81, 782785.CrossRefGoogle ScholarPubMed
Danso-Appiah, A. and de Vlas, S. J. (2002). Interpreting low praziquantel cure rates of Schistosoma mansoni infections in Senegal. Trends in Parasitology 18, 125129.CrossRefGoogle ScholarPubMed
Da Silva, I. M., Thiengo, R., Conceicao, M. J., Rey, L., Lenzi, H. L., Filho, E. P. and Ribeiro, P. C. (2005). Therapeutic failure of praziquantel in the treatment of Schistosoma haematobium infection in Brazilians returning from Africa. Memorias do Instituto Oswaldo Cruz 100, 445449.CrossRefGoogle Scholar
Doenhoff, M. J. (1998). Is schistosomicidal chemotherapy sub-curative? Implications for drug resistance. Parasitology Today 14, 434435.CrossRefGoogle ScholarPubMed
Doenhoff, M. J., Cioli, D. and Utzinger, J. (2008). Praziquantel: mechanisms of action, resistance and new derivatives for schistosomiasis. Current Opinion in Infectious Diseases 21, 659667.CrossRefGoogle ScholarPubMed
Doenhoff, M. J. and Pica-Mattoccia, L. (2006). Praziquantel for the treatment of schistosomiasis: its use for control in areas with endemic disease and prospects for drug resistance. Expert Reviews in Anti-Infective Therapy 4, 199210.CrossRefGoogle ScholarPubMed
Doenhoff, M. J., Sabah, A. A., Fletcher, C., Webbe, G. and Bain, J. (1987). Evidence for an immune-dependent action of praziquantel on Schistosoma mansoni in mice. Transactions of the Royal Society of Tropical Medicine and Hygiene 81, 947951.CrossRefGoogle ScholarPubMed
Engels, D., Chitsulo, L., Montresor, A. and Savioli, L. (2002). The global epidemiological situation of schistosomiasis and new approaches to control and research. Acta Tropica 82, 139146.CrossRefGoogle ScholarPubMed
Fallon, P. G. and Doenhoff, M. J. (1994). Drug-resistant schistosomiasis: resistance to praziquantel and oxamniquine induced in Schistosoma mansoni in mice is drug specific. American Journal of Tropical Medicine and Hygiene 51, 8388.CrossRefGoogle ScholarPubMed
Fallon, P. G., Mubarak, J. S., Fookes, R. E., Niang, M., Butterworth, A. E., Sturrock, R. F. and Doenhoff, M. J. (1997). Schistosoma mansoni: maturation rate and drug susceptibility of different geographic isolates. Experimental Parasitology 86, 2936.CrossRefGoogle ScholarPubMed
Fenwick, A. (2006). New initiatives against Africa's worms. Transactions of the Royal Society of Tropical Medicine and Hygiene 100, 200207.CrossRefGoogle ScholarPubMed
Fenwick, A., Savioli, L., Engels, D., Bergquist, R. N. and Todd, M. H. (2003). Drugs for the control of parasitic diseases: current status and development in schistosomiasis. Trends in Parasitology 19, 509515.CrossRefGoogle ScholarPubMed
Gryseels, B., Mbaye, A., de Vlas, S. J., Stelma, F. F., Guisse, F., Van Lieshout, L., Faye, D., Diop, M., Ly, A., Tchuem-Tchuente, L. A., Engels, D. and Polman, K. (2001). Are poor responses to praziquantel for the treatment of Schistosoma mansoni infections in Senegal due to resistance? An overview of the evidence. Tropical Medicine and International Health 6, 864873.CrossRefGoogle ScholarPubMed
Guisse, F., Polman, K., Stelma, F. F., Mbaye, A., Talla, I., Niang, M., Deelder, A. M., Ndir, O. and Gryseels, B. (1997). Therapeutic evaluation of two different dose regimens of praziquantel in a recent Schistosoma mansoni focus in Northern Senegal. American Journal of Tropical Medicine and Hygiene 56, 511514.CrossRefGoogle Scholar
Hagan, P., Appleton, C. C., Coles, G. C., Kusel, J. R. and Tchuem-Tchuente, L. A. (2004). Schistosomiasis control: keep taking the tablets. Trends in Parasitology 20, 9297.CrossRefGoogle ScholarPubMed
Harnett, W. and Kusel, J. R. (1986). Increased exposure of parasite antigens at the surface of adult male Schistosoma mansoni exposed to praziquantel in vitro. Parasitology 93, 401405.CrossRefGoogle ScholarPubMed
Hotez, P. J., Molyneux, D. H., Fenwick, A., Kumaresan, J., Ehrlich Sachs, S., Sachs, J. D. and Savioli, L. (2007). Control of neglected tropical diseases. New England Journal of Medicine 357, 10181027.CrossRefGoogle ScholarPubMed
Ismail, M., Metwally, A., Farghaly, A., Bruce, J., Tao, L. F. and Bennett, J. L. (1996). Characterization of isolates of Schistosoma mansoni from Egyptian villagers that tolerate high doses of praziquantel. American Journal of Tropical Medicine and Hygiene 55, 214218.CrossRefGoogle ScholarPubMed
Jeziorski, M. C. and Greenberg, R. M. (2006). Voltage-gated calcium channel subunits from platyhelminths: potential role in praziquantel action. International Journal for Parasitology 36, 625632.CrossRefGoogle ScholarPubMed
Johansen, M. V., Sacko, M., Vennervald, B. J. and Kabatereine, N. B. (2007). Leave children untreated and sustain inequity! Trends in Parasitology 23, 568569.CrossRefGoogle ScholarPubMed
Kabatereine, N. B., Kemijumbi, J., Ouma, J. H., Sturrock, R. F., Butterworth, A. E., Madsen, H., Ornbjerg, N., Dunne, D. W. and Vennnervald, B. J. (2003). Efficacy and side effects of praziquantel treatment in a highly endemic Schistosoma mansoni focus at Lake Albert, Uganda. Transactions of the Royal Society of Tropical Medicine and Hygiene 97, 599603.CrossRefGoogle Scholar
Karanja, D. H. S., Boyer, A. E., Strand, M., Colley, D. G., Nahlen, B. L., Ouma, J. H. and Secor, W. E. (1998). Studies on schistosomiasis in western Kenya: II. Efficacy of praziquantel for treatment of schistosomiasis in persons coinfected with human immunodeficiency VIRUS-1. American Journal of Tropical Medicine and Hygiene 59, 307311.CrossRefGoogle ScholarPubMed
Katz, N. and Coelho, P. M. (2008). Clinical therapy of schistosomiasis mansoni: the Brazilian contribution. Acta Tropica 108, 7278.CrossRefGoogle ScholarPubMed
Keiser, J., Chollet, J., Xiao, S. H., Mei, J. Y., Jiao, P. Y., Utzinger, J. and Tanner, M. (2009). Mefloquine – an amionoalcohol with promising antischistosomal properties in mice. PLoS Neglected Tropical Diseases 3, e350.CrossRefGoogle ScholarPubMed
Keiser, J., El Ela, N. A., El Komy, E., El Lakkany, N., Diab, T., Chollet, J., Utzinger, J. and Barakat, R. (2006). Triclabendazole and its two main metabolites lack activity against Schistosoma mansoni in the mouse model. American Journal of Tropical Medicine and Hygiene 75, 287291.CrossRefGoogle ScholarPubMed
Keiser, J. and Utzinger, J. (2007). Artemisinins and synthetic trioxolanes in the treatment of helminth infections. Current Opinion in Infectious Diseases 20, 605612.CrossRefGoogle ScholarPubMed
King, C. H. and Bertino, A. M. (2008). Asymmetries of poverty: why global burden of disease valuations underestimate the burden of neglected tropical diseases. PLoS Neglected Tropical Diseases 2, e209.CrossRefGoogle ScholarPubMed
King, C. H. and Dangerfield-Cha, M. (2008). The unacknowledged impact of chronic schistosomiasis. Chronic Illness 4, 6579.CrossRefGoogle ScholarPubMed
King, C. H., Dickman, K. and Tisch, D. J. (2005). Reassessment of the cost of chronic helmintic infection: a meta-analysis of disability-related outcomes in endemic schistosomiasis. Lancet 365, 15611569.CrossRefGoogle ScholarPubMed
Kohn, A. B., Roberts-Misterly, J. M., Anderson, P. A. and Greenberg, R. M. (2003 a). Creation by mutagenesis of a mammalian Ca(2+) channel beta subunit that confers praziquantel sensitivity to a mammalian Ca(2+) channel. International Journal for Parasitology 33, 13031308.CrossRefGoogle ScholarPubMed
Kohn, A. B., Roberts-Misterly, J. M., Anderson, P. A., Khan, N. and Greenberg, R. M. (2003 b). Specific sites in the Beta Interaction Domain of a schistosome Ca2+ channel beta subunit are key to its role in sensitivity to the anti-schistosomal drug praziquantel. Parasitology 127, 349356.CrossRefGoogle Scholar
Kuntz, A. N., Davioud-Charvet, E., Sayed, A. A., Califf, L. L., Dessolin, J., Arner, E. S. J. and Williams, D. L. (2007). Thioredoxin glutathione reductase from Schistosoma mansoni: an essential parasite enzyme and a key drug target. PloS Medicine 4, e206.CrossRefGoogle Scholar
Lammie, P. J., Fenwick, A. and Utzinger, J. (2006). A blueprint for success: integration of neglected tropical disease control programmes. Trends in Parasitology 22, 313321.CrossRefGoogle ScholarPubMed
Li, J., Wang, Y., Fenwick, A., Clayton, T. A., Lau, Y. Y. K., Legido-Quigley, C., Lindon, J. C., Utzinger, J. and Holmes, E. (2007). A high-performance liquid chromatography and nuclear magnetic resonance spectroscopy-based analysis of commercially available praziquantel tablets. Journal of Pharmaceutical and Biomedical Analysis 45, 263267.CrossRefGoogle ScholarPubMed
Liang, Y. S., Coles, G. C., Dai, J. R., Zhu, Y. C. and Doenhoff, M. J. (2001). Biological characteristics of praziquantel-resistant and -susceptible isolates of Schistosoma mansoni. Annals of Tropical Medicine and Parasitology 95, 715723.CrossRefGoogle ScholarPubMed
LoVerde, P. T., Dewald, J., Minchella, D. J., Bosshardt, S. C. and Damian, R. T. (1985). Evidence for host-induced selection in Schistosoma mansoni. Journal of Parasitology 71, 297301.CrossRefGoogle ScholarPubMed
Meyer, T., Seklijc, H., Fuchs, S., Bothe, H., Schollmeyer, D. and Miculka, C. (2009). Taste, a new incentive to switch to (R) praziquantel in schistosomiasis treatment. PLoS Neglected Tropical Diseases 3: e357.CrossRefGoogle Scholar
Montero, R. and Ostrosky, P. (1997). Genotoxic activity of praziquantel. Mutation Research 387, 123139.CrossRefGoogle ScholarPubMed
Montresor, A., Odermatt, P., Muth, S., Iwata, F., Raja'a, Y. A., Assis, A. M., Zulkifli, A., Kabatereine, N. B., Fenwick, A., Al-Awaidy, S., Allen, H., Engels, D. and Savioli, L. (2005). The WHO dose pole for the administration of praziquantel is also accurate in non-African populations. Transactions of the Royal Society of Tropical Medicine and Hygiene 99, 7881.CrossRefGoogle ScholarPubMed
Mwanakasale, V., Vounatsou, P., Sukwa, T. Y., Ziba, M., Ernest, A. and Tanner, M. (2003). Interactions between Schistosoma haematobium and human immunodeficiency virus type 1: the effects of coinfection on treatment outcomes in rural Zambia. American Journal of Tropical Medicine and Hygiene 69, 420428.CrossRefGoogle ScholarPubMed
N'Goran, E. K., Utzinger, J., Gnaka, H. N., Yapi, A., N'Guessan, N. A., Kigbafori, S. D., Lengeler, C., Chollet, J., Xiao, S. H. and Tanner, M. (2003). Randomized, double-blind, placebo-controlled trial of oral artemether for the prevention of patent Schistosoma haematobium infections. American Journal of Tropical Medicine and Hygiene 68, 2432.CrossRefGoogle ScholarPubMed
O'Boyle, C., Lambe, R. and Darragh, A. (1985). Central effects in man of the novel schistosomicidal benzodiazepine meclonazepam. European Journal of Clinical Pharmacology 29, 105108.CrossRefGoogle ScholarPubMed
Pereira, C., Fallon, P. G., Cornette, J., Capron, A., Doenhoff, M. J. and Pierce, R. J. (1998). Alterations in cytochrome-c oxidase expression between praziquantel-resistant and susceptible strains of Schistosoma mansoni. Parasitology 117, 6373.CrossRefGoogle ScholarPubMed
Pica-Mattoccia, L., Carlini, D., Guidi, A., Cimica, V., Vigorosi, F. and Cioli, D. (2006). The schistosome enzyme that activates oxamniquine has the characteristics of a sulfotransferase. Memorias do Instituto Oswaldo Cruz 101, 307312.CrossRefGoogle ScholarPubMed
Pica-Mattoccia, L. and Cioli, D. (2004). Sex- and stage-related sensitivity of Schistosoma mansoni to in vivo and in vitro praziquantel treatment. International Journal for Parasitology 34, 527533.CrossRefGoogle ScholarPubMed
Pica-Mattoccia, L., Doenhoff, M. J., Valle, C., Basso, A., Troiani, A.-R., Liberti, P., Festucci, A., Guidi, A. and Cioli, D. (2009). Genetic analysis of decreased praziquantel sensitivity in a laboratory strain of Schistosoma mansoni. Acta Tropica (In Press). doi:10.1016/j.actatropica.2009.01.012.CrossRefGoogle Scholar
Pica-Mattoccia, L., Orsini, T., Basso, A., Festucci, A., Liberti, P., Guidi, A., Marcatto-Maggi, A. L., Nobre-Santana, S., Troiani, A. R., Cioli, D. and Valle, C. (2008). Schistosoma mansoni: lack of correlation between praziquantel-induced intra-worm calcium influx and parasite death. Experimental Parasitology 119, 332335.CrossRefGoogle ScholarPubMed
Pica-Mattoccia, L., Ruppel, A., Xia, C. M. and Cioli, D. (2007 a). Praziquantel and the benzodiazepine Ro 11-3128 do not compete for the same binding sites in schistosomes. Parasitology 135, 4754.CrossRefGoogle Scholar
Pica-Mattoccia, L., Valle, C., Basso, A., Troiani, A. R., Vigorosi, F., Liberti, P., Festucci, A. and Cioli, D. (2007 b). Cytochalasin D abolishes the schistosomicidal activity of praziquantel. Experimental Parasitology 115, 344351.CrossRefGoogle ScholarPubMed
Picquet, M., Vercruysse, J., Shaw, D. J., Diop, M. and Ly, A. (1998). Efficacy of praziquantel against Schistosoma mansoni in northern Senegal. Transactions of the Royal Society of Tropical Medicine and Hygiene 92, 9093.CrossRefGoogle ScholarPubMed
Renganathan, E. and Cioli, D. (1998). An international initiative on praziquantel use. Parasitology Today 14, 390391.CrossRefGoogle ScholarPubMed
Sabah, A. A., Fletcher, C., Webbe, G. and Doenhoff, M. J. (1986). Schistosoma mansoni: chemotherapy of infections of different ages. Experimental Parasitology 61, 294303.CrossRefGoogle ScholarPubMed
Sacko, M., Magnussen, P., Traoré, M., Doucouré, A., Reimert, C. M. and Vennervald, B. J. (2009). The effect of single dose versus two doses of praziquantel on Schistosoma haematobium infection and pathology among school-aged children in Mail. Parasitology 136 (in press).CrossRefGoogle Scholar
Sheir, Z., Nasr, A. A., Massoud, A., Salama, O., Badra, G. A., El-Shennawy, H., Hassan, N. and Hammad, S. M. (2001). A safe, effective, herbal antischistosomal therapy derived from myrrh. American Journal of Tropical Medicine and Hygiene 65, 700704.CrossRefGoogle ScholarPubMed
Simeonov, A., Jadhav, A., Sayed, A. A., Wang, Y., Nelson, M. E., Thomas, C. J., Inglese, J., Williams, D. L. and Austin, C. P. (2008). Quantitative high-throughput screen identifies inhibitors of the Schistosoma mansoni redox cascade. PLoS Neglected Tropical Diseases 2, e127.CrossRefGoogle ScholarPubMed
Southgate, V. R. (1997). Schistosomiasis in the Senegal River Basin: before and after the construction of the dams at Diama, Senegal and Manantali, Mali and future prospects. Journal of Helminthology 71, 125132.CrossRefGoogle ScholarPubMed
Southgate, V. R., Rollinson, D., Tchuem Tchuenté, L. A. and Hagan, P. (2005). Towards control of schistosomiasis in sub-Saharan Africa. Journal of Helminthology 79, 181185.CrossRefGoogle ScholarPubMed
Stelma, F. F., Sall, S., Daff, B., Sow, S., Niang, M. and Gryseels, B. (1997). Oxamniquine cures Schistosoma mansoni infection in a focus in which cure rates with praziquantel are unusually low. Journal of Infectious Diseases 176, 304307.CrossRefGoogle Scholar
Stelma, F. F., Talla, I., Sow, S., Kongs, A., Niang, M., Polman, K., Deelder, A. M. and Gryseels, B. (1995). Efficacy and side effects of praziquantel in an epidemic focus of Schistosoma mansoni. American Journal of Tropical Medicine and Hygiene 53, 167170.CrossRefGoogle Scholar
Stohler, H. R. (1978). Ro 11-3128, a novel schistosomicidal compound. In Current Chemotherapy, (ed. Siegenthaler, W. and Luthy, R.), pp. 147148.Google Scholar
Stothard, J. R. and Gabrielli, A. F. (2007 a). Schistosomiasis in African infants and preschool children: to treat or not to treat. Trends in Parasitology 23, 8386.CrossRefGoogle ScholarPubMed
Stothard, J. R. and Gabrielli, A. F. (2007 b). Response to Johansen et al.: Leave children untreated and sustain inequity! Trends in Parasitology 23, 569570.CrossRefGoogle Scholar
Sturrock, R. F., Bain, J., Webbe, G., Doenhoff, M. J. and Stohler, H. (1987). Parasitological evaluation of curative and subcurative doses of 9-acridanone-hydrazone drugs against Schistosoma mansoni in baboons, and observations on changes in serum levels of anti-egg antibodies detected by ELISA. Transactions of the Royal Society of Tropical Medicine and Hygiene 81, 188192.CrossRefGoogle ScholarPubMed
Sulaiman, S. M., Traore, M., Engels, D., Hagan, P. and Cioli, D. (2001). Counterfeit praziquantel. Lancet 358, 666667.CrossRefGoogle ScholarPubMed
Tallima, H. and El Ridi, R. (2007). Praziquantel binds Schistosoma mansoni adult worm actin. International Journal of Antimicrobial Agents 29, 570575.CrossRefGoogle ScholarPubMed
Tchuem Tchuente, L. A., Southgate, V. R., Mbaye, A., Engels, D. and Gryseels, B. (2001). The efficacy of praziquantel against Schistosoma mansoni infection in Ndombo, northern Senegal. Transactions of the Royal Society of Tropical Medicine and Hygiene 95, 6566.CrossRefGoogle ScholarPubMed
Troiani, A. R., Pica-Mattoccia, L., Valle, C., Cioli, D., Mignogna, G., Ronketti, F. and Todd, M. (2007). Is actin the praziquantel receptor? International Journal of Antimicrobial Agents 30, 280281.CrossRefGoogle ScholarPubMed
Tsai, M. H., Marx, K. A., Ismail, M. M. and Tao, L. (2000). Randomly amplified polymorphic DNA (RAPD) polymerase chain reaction assay for identification of Schistosoma mansoni strains sensitive or tolerant to anti-schistosomal drugs. Journal of Parasitology 86, 146149.CrossRefGoogle ScholarPubMed
Utzinger, J., Booth, M., N'Goran, E. K., Müller, I., Tanner, M. and Lengeler, C. (2001). Relative contribution of day-to-day and intra-specimen variation in faecal egg counts of Schistosoma mansoni before and after treatment with praziquantel. Parasitology 122, 537544.CrossRefGoogle ScholarPubMed
Utzinger, J., N'Goran, E. K., N'Dri, A., Lengeler, C. and Tanner, M. (2000 a). Efficacy of praziquantel against Schistosoma mansoni with particular consideration for intensity of infection. Tropical Medicine and International Health 5, 771778.CrossRefGoogle ScholarPubMed
Utzinger, J., N'Goran, E. K., N'Dri, A., Lengeler, C., Xiao, S. H. and Tanner, M. (2000 b). Oral artemether for prevention of Schistosoma mansoni infection: randomised controlled trial. Lancet 355, 13201325.CrossRefGoogle ScholarPubMed
Utzinger, J., Xiao, S. H., Tanner, M. and Keiser, J. (2007). Artemesinins for schistosomiasis and beyond. Current Opinion in Investigational Drugs 8, 105116.Google Scholar
Valle, C., Troiani, A. R., Festucci, A., Pica-Mattoccia, L., Liberti, P., Wolstenholme, A., Francklow, K., Doenhoff, M. J. and Cioli, D. (2003). Sequence and level of endogenous expression of calcium channel beta subunits in Schistosoma mansoni displaying different susceptibilities to praziquantel. Molecular and Biochemical Parasitology 130, 111115.CrossRefGoogle ScholarPubMed
van Der Werf, M. J., de Vlas, S. J., Brooker, S., Looman, C. W. N., Nagelkerke, N. J. D., Habbema, J. D. F. and Engels, D. (2003). Quantification of clinical morbidity associated with schistosome infection in sub-Saharan Africa. Acta Tropica 86, 125139.CrossRefGoogle ScholarPubMed
Van Wyk, J. A. (2001). Refugia – overlooked as perhaps the most potent factor concerning the development of anthelmintic resistance. Onderstepoort Journal of Veterinary Research 68, 5567.Google ScholarPubMed
William, S., Sabra, A., Ramzy, F., Mousa, M., Demerdash, Z., Bennett, J. L., Day, T. A. and Botros, S. (2001). Stability and reproductive fitness of Schistosoma mansoni isolates with decreased sensitivity to praziquantel. International Journal for Parasitology 31, 10931100.CrossRefGoogle ScholarPubMed
Wu, M. H., Wei, C. C., Xu, Z. Y., Yuan, H. C., Lian, W. N., Yang, Q. J., Chen, M., Jiang, Q. W., Wang, C. Z., Zhang, S. J., Liu, Z. D., Wei, R. M., Yuan, S. J., Hu, L. S. and Wu, Z. S. (1991). Comparison of the therapeutic efficacy and side effects of a single dose of levo-praziquantel with mixed isomer praziquantel in 278 cases of schistosomiasis japonica. American Journal of Tropical Medicine and Hygiene 45, 345349.CrossRefGoogle ScholarPubMed
Van Nassauw, L., Toovey, S., Van Op den Bosch, J., Timmermans, J.-P. and Vercruysse, J. (2008). Schistosomicidal activity of the antimalarial drug, mefloquine, in Schistosoma mansoni-infected mice. Travel Medicine and Infectious Diseases 6, 253258.CrossRefGoogle ScholarPubMed
Xiao, S. H., Keiser, J., Chollet, J., Utzinger, J., Dong, Y., Vennerstrom, J. L. and Tanner, M. (2007). In vitro and in vivo activities of synthetic trioxolanes against major human schistosome species. Antimicrobial Agents and Chemotherapy 51, 14401445.CrossRefGoogle ScholarPubMed