Parasitology into the 21st Century

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  • Makuhari, Chiba, JapanAugust 1998

    The opening of this ninth InternationalCongress of Parasitology (ICOPA9) wasgraced by the presence of the Emperorand Empress of Japan. The Emperor, him-self a biologist, delivered a congratulatoryaddress that included a historical reviewof parasites and of their control in Japan,and that stressed his intense concernabout the burden that parasitic diseaseplaces on the world. This speech wasespecially appropriate in light of the re-cent pronouncement of a global controlscheme of parasitic diseases (HashimotoInitiative) by the former Prime Ministerof Japan, R. Hashimoto, at BirminghamSummit in May 1998. In a press releaseat the time, he proposed that Japan launcha global parasite control effort in collabo-ration with other G7 countries and inter-national organizations such as WHO.

    The Past and The Future

    In a historical review of parasitologyand parasitologists in Japan during the past100 years and more, Y. Yoshida (KyotoPrefectural University, Japan) outlined therelevance of Confucian thought, wheretaking a leaf out of a wisemans book cancarry knowledge into new fields, andstated that this idea has application toparasitological research in the new cen-tury. He introduced historical records ofparasitic diseases (such as malaria andfilariasis; see Fig.1) in the 12th and 13thcenturies, and spoke about the nowlargely forgotten Japanese pioneers en-gaged in the early investigations, includ-ing: Y. Fujii, F. Katsurada and K. Miyairi inschistosomiasis, S. Kobayashi and M. Mutoin clonorchiasis, and K. Nakagawa in para-gonimiasis. Yoshida stated that the con-tributions of these early workers are aprecious legacy for future studies in para-sitology, since only a few senior parasitol-ogists remain who can vividly recall en-demic diseases such as malaria, filariasisand schistosomiasis, which were rampantonly decades ago in Japan. Most of theyounger parasitologists have never en-countered parasitic diseases in the field.

    In his keynote address, H. Spencer(London School of Hygiene & TropicalMedicine, UK) referred to the importanceof molecular biology in furthering ourunderstanding of pathogenesis, a technol-ogy that should soon lead to new targets

    for drugs and for vaccines. He averredthat establishment of sustainable strat-egies is a sine qua non for the control of parasitic infections in the field. TheInternet was touted as an important tool for research and control. T. Godal(WHO, Switzerland) introduced theirnew policy to fight infectious and para-sitic diseases, one of the most importantbeing Rollback Malaria. While beingaware that the current global economicsituation might de-rail global controlprograms and research, we need to beproactive in the arena of control.

    Parasite Control

    Because a huge number of paperswas presented in the Congress, it is im-possible to summarize even the mostoutstanding ones; we will only touchupon some interesting ideas and datadealing with parasite control, which byall accounts will be among the mostimportant goals in the early years of the next century. In reference to malaria,S.L. Hoffman (Naval Medical ResearchInstitute, USA) suggested that two typesof vaccine are required1: one for non-immune travelers; and the other forchildren and pregnant women living inendemic areas. Based on recent DNAvaccine trials, it appears that we areabout to enter a new phase in terms ofgene technology, including direct injec-tion of naked DNAs, and the use of gene

    guns and hybrid viruses (R.C. Kennedy,University of Oklahoma Health ServicesCenter, USA). There are, however, cer-tain problems to be overcome, such asmajor histocompatibility complex (MHC)restrictions. With regard to schisto-somiasis, A. Capron (Institute Pasteur deLille, France) reviewed the 40 years waragainst this affliction2, and emphasizedthe key role played by the develop-ment of vaccine that is now in field use.An important development is a 29 kDaglutathione-S-transferase which showssignificant worm anti-fecundity activity.D. Harn (Harvard School of Health, USA)spoke about recent progress of DNAvaccine, and the discovery of a newoligosaccharide adjuvant.

    Another symposium, entitled Newapproach to control of schistosomosis,proposed a number of alternative con-trol strategies, such as anti-pairing [M.A.Haseeb, State University of New York(SUNY), USA], traps for miracidia/cer-caria (W. Haas, University of Erlangen,Germany), drug prophylaxis (S.H. Xiao,Chinese Academy of Preventive Medi-cine, China), and anti-fibrotic treatment(M. Giboda, San Juan Bautista School ofMedicine, Puerto Rico). These presen-tations show how various technologiescan be marshalled against a clever and elu-sive enemy. Although there still remainssome skepticism with regard to cost, skillsand sustainability, the geographical in-formation system (GIS), remote sensing

    Parasitology Today, vol. 15, no. 3, 1999 850169-4758/99/$ see front matter 1999 Elsevier Science. All rights reserved. PII: S0169-4758(99)01392-7


    Parasitology into the 21st CenturyI. Tada, M. Aikawa, Y. Aoki and F. Sendo

    Fig. 1. An illustration in Yamaizoshi of leg elephantiasis in a woman approximately700800 years ago, which is preserved in the Tokyo National Museum. Reproduced,with permission, from the Tokyo National Museum.

  • and the Internet could have a significantimpact in the very near future (B.L. Wood,NASA, USA; S.J. Connor, Liverpool Schoolof Tropical Medicine, UK; K.R. Hata,WHO, Switzerland). Financial support isfundamental to the quest for adequateparasite control. E. Ottesen (Division ofControl of Tropical Diseases, WHO,Switzerland) announced the start of acollaborative global elimination programof lymphatic filariasis between WHO anda pharmaceutical company (SmithKlineBeecham), which decided to donate aneffective antifilarial drug, for a 20 yearterm3,4. By integrating all available finan-cial and scientific resources, we hope toattain a parasite-free world early in the21st century.

    This congress provided a golden op-portunity for young parasitologists, es-pecially Japanese ones, to encounter anumber of eminent scientists, such as theNobel laureate P.C. Doherty, whose

    works were hitherto known only fromjournals. At the same time, the seriousnessof parasitic diseases was driven home. Itis hoped that such exposure will inspireveterans and tyros alike to increase theirefforts in the study of parasitology.

    AcknowledgementsICOPA9 was held, 2428 August 1998, withthe participation of 1270 registered personsfrom 81 different countries. ICOPA9 was or-ganized by the Science Council of Japan andthe Japanese Society of Parasitology under theauspices of the World Federation of Para-sitologists. The organizing committee plannedappropriate keynote speeches and lectures de-signed to usher parasitology into the 21st cen-tury. The program comprised four keynoteaddresses, eight special lectures, 43 symposia(including two forums), 11 workshops, 492 oralpresentations and 412 posters. The currenteconomic crises in Asia and East Europe pre-vented the attendance of a number of partici-pants, especially in the fields of epidemiology

    and control, so that a number of presentationsunfortunately had to be cancelled. The pro-ceedings are published by Monduzzi Editore,Bologna, Italy.

    References1 Hoffman, S.L. (1997) Ann. Intern. Med. 127,

    2332352 Capron, A. (1998) Parasitol. Today 14, 3793843 WHO (1998) WHO, SmithKline Beecham to

    cooperate on elephantiasis elimination. PressRelease WHO/12 26

    4 Ottesen, E.A. et al. (1997) Bull. WHO 75, 491503

    Isao Tada is at the Department of Parasitology,Faculty of Medicine, Kyushu University, Fukuoka,Japan. Masamichi Aikawa is at the Institute ofMedical Sciences, Tokai University, Isehara, Japan.Yoshiki Aoki is at the Department of Parasitology,Institute of Tropical Medicine, Nagasaki University,Nagasaki, Japan. Fujiro Sendo is at the Depart-ment of Immunology and Parasitology, Faculty ofMedicine, Yamagata University, Yamagata, Japan.Tel: 181 92 642 6116, Fax: 181 92 6426115, e-mail:

    Edinburgh, UKSeptember 1998

    In keeping with the 100th anniversary of Ronald Rosss discovery of the malariaparasite in the mosquito vector, the open-ing talks at this 10th BSP (British Societyfor Parasitology) Malaria Meeting were onmosquito transmission. Prof. Fotis Kafatos(EMBL, Heidelberg, Germany) presentedhis extensive work on mosquito immuneresponses to parasite infection. Continu-ing the theme, Will Roeffen (AcademicHospital, Nijmegen, The Netherlands) de-scribed preliminary results using phagedisplay techniques to identify monoclonalantibodies that block malaria transmission.On mosquito behaviour, Rob Anderson(Simon Fraser University, Burnaby, BritishColumbia, Canada) presented workshowing that infected mosquitoes exhibitrespectively less or more persistence inbiting than do uninfected mosquitoes, de-pending upon whether they are infectedwith oocysts or sporozoites. Such changesin biting rate and survival strategies havesignificant implications on traditional mod-els of mosquito transmission. A tributeto Ronald Ross from Ted Nye, his biog-rapher1,2, concluded the session.

    Delegates then moved to theEdinburgh Traverse Theatre where athought-provoking play entitled Thehidden cycle by Stephen Horrobin pre-sented a lively and controversial debatebetween Ronald Ross, the anthropo-morphized spirit of malaria and malariascientists from Africa and the Westtoday.

    Molecular Genetics

    Andy Waters (University of Leiden,The Netherlands) gave an overview of progress and potential for transfec-tion technology and the advantages anddisadvantages of mechanisms feasible in Plasmodium knowlesi, P. berghei and P. falciparum. In a prize-winning poster,Katherine Trenholme (Menzies Schoolof Tropical Health Research, Darwin,Australia), described the use of transfec-tion techniques to disrupt a newly dis-covered cytoadherence-linked asexualgene (CLAG) on chromosome 9, dem-onstrating dramatic reduction in the abil-ity of the transfected parasites to adhereto melanoma cells. Cytoadherence wasalso addressed by David Roberts (Uni-versity of Oxford, UK), who described

    characterization of a novel adhesivephenotype, distinct from rosetting, whichwas associated with severe disease inKenyan children.

    Var-gene polymorphism and expres-sion of different forms of PfEMP-1 as ameans of evading human host immunity,were the focus of several presentations.Peter Preiser (NIMR, London, UK),however, presented work showing thattranscription of different forms of amalaria multigene family can occur evenwithin a single parasite, so that a differ-ential growth rate selection mechanismmay be present within each schizontprior to any immune pressure. Extra-chromosomal DNA, particularly theplastid circle, continues to be an attrac-tive target for malaria control, and CraigRoberts (University of Strathclyde, UK)described elegant work on inhibition ofthe shikimate pathway in apicomplexanparasites.

    Surprisingly, there was little newwork on drugs or vaccines. Trials of acombination of recombinant portions ofMSA-2, MSP-1 and RESA as describedby Christine Rzepczyk [QueenslandInstitute of Medical Research (QIMR),Brisbane, Australia] failed to protect

    86 Parasitology Today, vol. 15, no. 3, 19990169-4758/99/$ see front matter 1999 Elsevier Science. All rights reserved. PII: S0169-4758(99)01391-5


    The Spirit of Malaria: 100 Years of Parasites and Policies

    A. Creasey