A portal to the field

The Encyclopedia of Arthropod-transmitted Infectionsedited by M.W. Service and R.W. Ashford, CABI Publishing, 2002. US$185.00 (hbk) (600 pages)ISBN 0 851 99473 3Is there a need for a hard copy encyclopedia given the rapid searching availability of the internet? Entering ‘arthropod-transmitted infections’ into PubMed yields quite a superficial list of 12 results, although entering ‘arthropods and infections’ results in an overwhelming 4744 hits. By contrast, The Encyclopedia of Arthropod-transmitted Infections provides an easy entree into specific infections, even if the query starts with only the name of a disease, an infectious agent or an arthropod vector. Unlike more specialized texts focused on specific arthropod vectors or disease agents, this Encyclopedia does not require the user to know if the vector is an insect or a tick, or if the pathogen is a virus or a bacterium. Uncommon in most scientific reference texts, the entries are listed alphabetically, rather than by any taxonomic separations of the vector, pathogen or host species. However, this works well for the user because the entries are extensively cross-listed. For example, if the user starts their search using the terms ‘plague’, ‘Yersinia pestis’, or ‘fleas’, they will be directed to the most appropriate comprehensive entry, which is listed under the disease name. Once directed to the appropriate entry, the user has access to a summary of the vector, pathogen, and disease, and to a selected bibliography. Armed with this introductory knowledge, the search capabilities of the internet now become useful.The entries themselves are written by experts in their fields – I found that most of the entries on subjects of which I had little knowledge rapidly provided me with information to dig further into the topic. Moreover, I found that many of the entries for topics of which I have some previous knowledge were well written and, at the survey level appropriate for an encyclopedia, comprehensive. The most useful entries were those written by individuals who work on both the arthropod-vector and the pathogen. For example, the section on Anaplasmosis, written by Katherine Kocan (pp. 28–33), is contemporary and succinctly covers the mammalian infection and development of the pathogen within the tick vector. However, other entries were less comprehensive and occasionally inaccurate, probably reflecting a bias towards the disease in an animal or human host, the arthropod or the pathogen. For example, the statement in the section on the Rickettsiales that ‘insect transmission occurs for Rickettsia and Ehrlichia’ (p. 424) is misleading because most of these pathogens are transmitted by ticks; ticks are in a different class of the Phylum Arthropoda to insects.The most significant deficiency in the Encyclopedia is a lack of consistency in the depth of presentation among the entries. Some entries, such as the coverage of Theileriosis written by Patricia Preston (pp. 487–502), are extensive and accompanied by elucidating graphics, tables and photomicrographs. Other entries, however, are minimal in coverage and either do not include needed illustrations, or incorporate uninformative and, occasionally, simply bizarre photographs. Throughout the Encyclopedia, there are multiple pictures of individuals spraying insecticide along the walls of huts, or similarly impoverished dwellings in tropical regions – it is possible there would be a reader who could not envision how spraying would occur, but it seems a low return on investment when many entries are in need of a photograph or graphic illustration. The most baffling selection of a photograph has to be the picture of the automobile (p. 410) used to illustrate a natural focus of Powassan virus! (The main point might be that the initial outbreak was described in 1958, which would match the apparent vintage of the car.) Although the difficulties of compiling the efforts of many authors can be appreciated, the Encyclopedia would have benefited from a much stronger editorial hand in standardizing entry information and illustration.The Encyclopedia of Arthropod-transmitted Infections could well find its best use in serving the needs of those outside the field of arthropod-transmitted infections. Scientists and faculty with expertise in the field will direct chapter-level enquiries towards more specialized texts focused on the specific pathogen, vector, or epidemiology and pathogenesis of the disease. Although the Encyclopedia will be of some help to newcomers to the field (e.g. entering graduate students or post-doctoral students re-directing their investigation to arthropod-borne pathogens), these individuals will also need a more comprehensive understanding of the biology of the host–vector–pathogen triad than can be gained from an encyclopedic approach. By contrast, however, the Encyclopedia will be an excellent addition for those engaged in general biology instruction or introductory-level microbiology and entomology teaching, in which selection of specific examples of vector-borne diseases is needed. Similarly, physicians, nurses, veterinarians and other scientists with involvement in public and animal health might find the Encyclopedia an important information portal for arthropod-transmitted infections.