The malaria challenge after 100 years of malariology. Parassitologia 41, 1–3. September 1999, 528 pp.

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This special hard cover issue of Parassitologia includes a collection of state-of-the-art reviews and original articles presented at the Malariology Centenary Conference organized by the Società Italiana di Parassitologia and Royal Society of Tropical Medicine and Hygiene, UK at the Accademia Nazionale dei Lincei, Roma, 16–17 November 1998. The Conference marked the scientific achievements and challenges in malariology during the 100 years since Grassi and Ross discovered the mosquito's role in the malaria life cycle and transmission. The meeting also brought together institutions that sustained the foundation for the successful eradication in early years, and now are involved in the ongoing effort to control malaria in endemic areas.

Although immense and diverse progress has been made in malaria research, endemic areas still bear a huge burden of morbidity and mortality. In the opening lecture entitled ‘The last and the next hundred years of malariology’, Professor David Bradley underscored the uniqueness of the conference and of this publication, stressing that malariology today is an area of knowledge composed of the interacting population genetics of the malaria parasites, humans and anopheline vectors: ‘Future research will be as much about linking different scales of the understanding (of these populations) as control will be about linking different levels of the health system’. The Centenary Conference and this publication also mark the foundation of the African Malaria Society which may play a significant role in the near future in any concerted malaria control effort in Africa.

The book contains 85 papers, with each chapter reflecting the format of the conference sessions. Highlights of each chapter are listed. The first chapter on historical perspectives reviews key developments and milestones such as contributions from the Italian School of Malariology at the end of 19th century; the discoveries of Laveran, Manson, Grassi and others; the epistemological aspects of the debate between Grassi and Ross on their role in the discovery of the human malaria cycle; and Ross's research in India, during which he elucidated the role of the Anopheles mosquito in the transmission of the disease.

The second chapter covers evolutionary and genetic backgrounds, describing DNA analysis of the evolution of the four human parasites; the shotgun approach used to sequence the parasite genes found in P .falciparum chromosome 2; the evolution of the human genome under selective pressure from malaria; host genetic control of malaria infection linked to chromosome 5q31-q33; the molecular evolution of Plasmodium; the natural selection on immunogenic regions for T-cell epitopes and regions linked to host antibodies; cytogenetic and molecular data on Anopheles speciation; evolutionary relationships among cryptic taxa, gene flow, population structure, introgression, sibling species, individual chromosomal forms and natural chromosomal inversion of the An. gambiae complex.

Human–parasite vector interactions are the subject of the third chapter, which includes papers describing a wide range of molecular approaches to understanding mechanisms and mediators of pathogenesis, host immune responses, susceptibility, gametogenesis, sporozoite production and genetic manipulation and behaviour research of An. gambiae. Possible mechanisms to explain defence reactions within the mosquito are described as well as mechanisms associated with haemoglobin metabolism by the parasites and pathogenesis of the disease in host with different haemoglobin varieties.

Infection and disease epidemiology, the next focus, presents a review of mathematical models of parasite reproductivity rate; the critical molecular pathway of different mediators of immunity and pathogenesis; the impact of interventions on and the relationship between malaria transmission, clinical presentation, immunity, morbidity and mortality; genotyping studies of successive malaria attacks; clinical presentation of malaria in migrants and nonimmune subjects; morphological, behavioural and genetical differences within vector species; diversity of malaria patterns in rice cultivation areas; and theories on the origin, spread and control of P. falciparum.

Chapter 5 deals with case management of severe malaria and personal protection; antimalarial combination therapy as a strategy to reduce selection of drug resistant parasites and parasite mutation; development of new antimalarials and studies on mechanisms of action and possible drug potentiation; mechanisms of insecticide resistance and distribution of pyrethroid resistance genes (kdr); re-emergence of malaria in WHO European region; malaria control priorities and constraints at community and health service levels.

The section on implementation of malaria control discusses needs and opportunities in sub-Saharan Africa; approaches for prevention and control of epidemics; the malaria situation in India and the Americas; the involvement of the Italian Development Co-operation in malaria control in Africa; the success of the community-based malaria programme in Tigray, Ethiopia; epidemic control on the highlands of Madagascar; impact of the bednets programme in Burkina Faso; a chemotherapy programme in the Solomon Islands; effectiveness of insecticidal methods for vector control; and finally an analysis of the impact of national structural adjustment programmes on malaria resurgence.

The penultimate chapter reviews advances in the field of vaccine discovery and development. The contributors examine mechanisms of protective immunity in the search for the best vaccine candidate; immune response to pre-erythrocytic and to asexual blood stage vaccine candidates (CS repeat sequences and merozoite surface protein 1 – (MSP1), respectively); different approaches to generating a multicomponent multiantigen vaccine candidate, including peptide-based constructs; plasmid DNA vectors expressing target genes in vivo; attenuated vector (vaccinia virus) expressing malaria genes; and combinations of recombinant proteins with adjuvants such as RTS,S. The potential impact of transmission-blocking vaccination on morbidity and immunity is discussed. Key issues in the development, clinical testing and biological properties of a malaria vaccine are also highlighted.

Lastly, new areas of research and emerging technologies are introduced, including the use of meteorological data in environmental information systems (EIS) for forecasting and preventing epidemics; different approaches to develop new chemotherapeutical agents; development of genetically modified malaria parasites; genetically engineered Plasmodium-resistant mosquitoes; use of transgenic haematophagous insects as delivery system of vaccines; replacement of natural vector population by a Plasmodium-refractory one; and potential application of genomics in malaria entomology.

The final remarks and closing address carefully capture the comments provided by participants from leading research and control organizations on malaria control priorities and constraints. The role of research, including the Multilateral Initiative on Malaria (MIM) designed to promote international co-ordination on research; and the WHO-co-ordinated Roll Back Malaria Initiative which intends to halve malaria mortality by the year 2010, are discussed. A common agreement was the need for more sustained measures to control the disease. Overall, this special volume represents a historical landmark in malaria research and is an obligatory reference book for all malariologists.

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