Parasitology yesterday--following the trends

The 1980s were a period of great activity in the field of parasitology that generated a vast amount of research published in approximately 20 specialist and several other learned journals. There was, however, no vehicle for disseminating the exciting discoveries that were being made in an immediate, easily readable and accessible form suitable for teachers, students and others interested in aspects of the subject that were broader than their own particular specialty. To fill this perceived gap, Elsevier decided in 1985 that it would be worthwhile publishing Parasitology Today to complement its other successful Trends journals. In this article, I review the breadth of coverage of topics published during the first year of Parasitology Today, most of which continue to be of interest today.     

The Plasmodium vivax genome sequencing project

With the successful completion of the project to sequence the Plasmodium falciparum genome, researchers are now turning their attention to other malaria parasite species. Here, an update on the Plasmodium vivax genome sequencing project is presented, as part of the Trends in Parasitology series of reviews expanding on various aspects of P. vivax research.     

Modelling nematode populations: 20 years of progress

Mathematical models require a fine balance between biological detail and mathematical tractability. Models can now accommodate much more biological complexity but, nevertheless, they focus on elucidation of principles rather than exact predictions. In this article, I discuss the advances made in population modelling of nematode parasites since the first issues of Parasitology Today.     

Human Plasmodium liver stages in SCID mice: a feasible model?

In a recent issue of Parasitology Today, Stanley and Virgin have stressed the potential of B- and T-cell deficient mice, among which severe combined immunodeficiency (SCID) mice are most frequently used, as models for the study of parasites. One of the most tantalizing prospects has been in the development of liver stages (LS) of human Plasmodium.     

Protective immune mechanisms to ticks and tick-borne diseases of ruminants.

A workshop of the European Union (EU) Concerted Action Project on the Integrated Control of Ticks and Tick-borne diseases (CA-ICTTD) recently assessed protective immune mechanisms to ticks and tick-borne diseases. The consensus achieved there is summarized here by Patricia Preston and Frans Jongejan. The current understanding of this field is expanded upon by the accompanying articles, and Poster, in this special issue of Parasitology Today.     

Plasmodium parasite proteins and the infected erythrocyte

Erythrocyte modification by malaria proteins is linked to both disease severity and infection. In this issue of Trends in Parasitology, Templeton and Deitsch, and Horrocks and Muhia discuss recent work identifying a host-targeting (HT) signal on malaria proteins. This signal predicts a secretome of 300-400 effectors for the human malaria parasite Plasmodium falciparum, vastly expanding the number of potential vaccine and drug targets. The HT signal seems to be distinct from known cellular transport signals, which suggests that it might be a novel eukaryotic secretion signal.     

Insecticide-treated nets against malaria vectors and polystyrene beads against Culex larvae

In Parasitology Today in 1985, Curtis and Lines, and Curtis and Minjas presented the ideas of insecticide-treated nets and polystyrene beads for mosquito control. The former idea has grown to be a major component of the strategy for malaria prevention, especially in Africa. However, although polystyrene beads have been demonstrated to work extremely well, they have yet to be taken up on a major scale.     

Online searching of parasitology literature

To keep abreast of the expanding literature on parasitology is virtually a such full-time pursuit of source literature becomes impossible with other commitments, encouraging recourse to secondary sources such as abstracting journals, Current Contents, and even Parasitology Today. Another approach - increasingly used since its faltering introduction in the 1970s- involves online searching of computerized databases. Here, John Eyers and Angela Taylor review the application of such systems to parasitology.     

Where do we stand on the autoimmunity hypothesis of Chagas disease?

The question posed in the title elicits as much controversy today as it did when I wrote about this subject in the first issue of Parasitology Today 20 years ago. A consensus is now emerging that Trypanosoma cruzi, the etiological agent of Chagas disease, bears primary responsibility for producing chagasic pathology. Whether one or more of the autoimmune events described in human and experimental Chagas disease can contribute to, or aggravate, this pathology is the current question.     

Molecular methods for the detection and classification of Cryptosporidium

Cryptosporidiosis is a zoonotic disease caused by a parasitic protozoan belonging to the coccidial genus Cryptosporidium. Current laboratory methods are adequate for the detection of the infection when oocysts are present in great numbers, but more-sensitive means of identification are urgently required. In a recent issue of Parasitology Today, Carolyn Petersen has presented a review of the cell biology of this parasite'. Here, Kath Webster draws attention to the various methods involved in its detection and classification.     

Health research in Papua New Guinea

The Papua New Guinea Institute of Medical Research (PNGIMR) is one of the most respected health research institutions in the developing world, and its studies of the local health problems of PNG have consistently had international relevance. This article examines the structural and philosophical factors that have enabled the success of the PNGIMR, and presents the PNGIMR approach to research as a potential model for other disease-endemic countries. An overview of PNGIMR research into malaria and filariasis is given with selected examples as an introduction to a Trends in Parasitology series on health research in Papua New Guinea.     

Molecular approaches to malaria: MAM 2004 and beyond

This special issue of Trends in Parasitology comprises a collection of timely reviews arising from the 2nd Molecular Approaches to Malaria meeting held 1-5 February 2004 in Lorne, Australia, four years after the successful inaugural meeting. As the name suggests, Molecular Approaches to Malaria focused on the latest molecular developments in malaria research, and their biological and clinical implications. By no means is this special issue intended to represent a comprehensive recapitulation of all of the presentations at the meeting. Rather, the articles address, in more general terms, recent advances on broader themes that were prominent at Molecular Approaches to Malaria meeting 2004.     

Invasion by schistosome cercariae: neglected aspects in Schistosoma japonicum

Skin invasion by schistosome cercariae was recently discussed in Trends in Parasitology. However, only Schistosoma mansoni was considered, possibly because this species predominates in laboratory studies (at least outside China). One may be tempted to extrapolate from the "model" S. mansoni to other schistosomes, but Schistosoma japonicum must not be neglected. This schistosome is distinguishable from others (particularly S. mansoni) by virtue of its remarkable speed and success of migration, as well as by specific biochemical and immunological features. This leads to the hypothesis that S. japonicum is atypical with respect to the enzymes that facilitate skin penetration.     

The effects of host sex on transmission success

A recent debate in Parasitology Today explored the causes of gender-related differences in parasite infection, examining epidemiological patterns on the one hand, and interactions between host sex hormones and the immune response on the other. In this article, Richard Tinsley focuses on the simplified ecology of a host-parasite system in a desert environment. This enables a clear separation of the factors determining the levels of host invasion (including host behaviour) from those that modulate the survival of established worm burdens (including host physiology).     

Viruses of parasitic protozoa

Associations are increasingly recognized between parasitic protozoa and smaller organisms such as bacteria (see Parasitology Today 1, 143), and viruses. Their revelation, originally by ultrastructural studies, may now be indicated by observations of 'rogue bands' on gel electrophoresis of parasite nucleic acids. The origins and roles of parasite 'parasites' are still uncertain, but, as Michael Miles suggests here, they may prove of particular importance as agents to introduce genes for important immunogens into non-pathogenic protozoa for vaccine delivery.     

Reports from the cutting edge of parasitic genome analysis.

This new feature in Parasitology Today will host reports from the laboratories involved in genomics of parasites, be that sequencing, mapping or 'functional genomics' - the mining and analysis of the sequence datasets, and the development of postgenomics tools to examine gene expression, response to drugs and population variability. It will publicize new technology to wider audiences, let communities of researchers know about novel resources (particularly those available through the World Wide Web) and highlight significant advances in the understanding of parasitic genomes through functional genomics.     

Pathology of malaria-infected mosquitoes

Concepts of the basic case reproduction rate of malaria, or the vectorial capacity of malaria vectors, tend to assume that the behaviour of infected and non-infected mosquitoes will be similar. However, recent years have seen a series of studies demonstrating that mosquitoes infected with malaria or other parasites show many pathological features with important effects on their behaviour and on the transmission dynamics of the parasite. Parasitology Today will be featuring a series of reports discussing these effects and attempting to unravel the expected effects on parasite transmission dynamics; this article sets the scene.     

Veterinary parasitology: looking to the next millennium.

'Veterinary parasitology' has traditionally been concerned with the control of parasites of livestock and companion animals, with emphasis on chemotherapy and immunoprophylaxis. This will continue, but there must be less reliance on chemical control; the development of alternative strategies will be a major goal over the next ten years. Here, Andrew Thompson takes an optimistic look at the challenges, strengths and opportunities for veterinary parasitology as we enter the next millennium. In the space available here, he can only 'scratch the surface' about what the future holds for veterinary parasitology, and will attempt to identify the major trends that are emerging, some of which will be the subject of future in-depth articles in Parasitology Today.     

BOOK REVIEW…

Books Review in this article:
Dawes, Ben, ed. 1977. Advances in Parasitology. Vol. 15. Academic Press, 111 Fifth Ave., New York NY 10003, USA. xx + 409 pp. $36.25.
Kcan, H . H., Mott, I(. E. S: Russell. A. J. eds. 1978. Tropical Medicine and Parasitology. Classic Ii1ccstigation.c. 1'01s. I and 11. Corncll Univ. Press, 124 Roberts PI., Ithaca XY 14850. xxiii + G77 pp. $.50.00.
Reissig, J. L., ed. 1977. Microbial Interactions. Vol. 3 of Receptors and Recognition, Series B. Chapman and Hall, London. + 436 pp. $39.50.
'Taylor, Angela E. R. Sr Muller. R.: eds. 1978. Thc Rclccance of ParaJitology to Human Welfare Today. Symbosiuin .Vo. 16 of the British Society for Pnrasitolo, qy. Blackwell Scientific Puhlications, Osney Mead, Oxford 0 5 2 OEL. England and J. B. Lippincott Co., East Washington Squaw, Philadelphia PA 191 0.5, L viii + 135 pp. $18.75.