Anniversaries are often occasions for celebration. Not this one. As the World Health Organization (WHO) reminds us, we are now one year into the deadly Ebola epidemic that has claimed the lives of thousands of persons in Guinea, Liberia, and Sierra Leone. Fortunately, it appears that a turning point in the epidemic may have been reached.
WHO has recently issued a series of 14 papers that examine this first epidemic of Ebola virus disease in West Africa, including Introduction; Origins of the Ebola epidemic; Factors that contributed to undetected spread; Guinea: The virus shows its tenacity; Liberia: A country and its capital are overwhelmed; Sierra Leone: A slow start to an outbreak that eventually outpaced all others; Key events in the WHO response; WHO technical support – a lasting impact?; Modernizing the arsenal of control tools: Ebola vaccines; Classical Ebola virus disease in DRC; Successful Ebola responses in Nigeria, Senegal, Mali; The importance of preparedness – everywhere; The warnings the world did not heed; and What needs to happen in 2015.
These reports reveal several of the facets of Ebola. First, there’s the Ebola virus itself. Then there’s Ebola virus disease. Then we have the Ebola epidemic, as well as vaccines to prevent the disease and various therapies to treat the disease.
A WebDewey search on "Ebola" retrieves 0 records (!), even when searched against All Fields. To find where works on any of the facets of Ebola should be classed in the DDC, we need to know a little more about the virus first. The website for the Centers for Disease Control and Prevention (CDC) provides us with the information that we need: "Ebola is caused by infection with a virus of the family Filoviridae, genus Ebolavirus." Or we could go to the MeSH browser, where a search on “Ebola virus” would lead us to this entry for the MeSH heading "Ebolavirus":
A search in WebDewey on "Filoviridae" takes us to 579.256 Single-stranded, enveloped RNA viruses, where Filoviridae is in the including note. This provides us with both one number of interest to us (i.e., the number where the Ebola virus should be classed) and the kind of virus that it is (i.e., an RNA virus). An example of a work on the Ebola virus itself, classed in 579.256, is Ebola and Marburg viruses: molecular and cellular biology.
Searching on "RNA virus*" takes us also to 614.588 RNA virus infections and to 616.918 RNA virus infections. Of course we need to know the hierarchy above 614.588 and 616.918 to know the meanings of those classes and how they differ from one other. We find:
Ascending the upward hierarchy of 614.588, we come to 614 Forensic medicine; incidence of injuries, wounds, disease; public preventive medicine, of which we are concerned with the incidence of disease and public preventive medicine. A little investigation takes us to 614.4 Incidence of and public measures to prevent disease, which has a class-here note reading, "Class here epidemiology," and a see reference reading, "For incidence of and public measures to prevent specific diseases and kinds of diseases, see 614.5." So we find that 614.588 is the epidemiology of RNA virus infections (including Ebola); Ebola epidemics would be classed there. Since Ebola is in standing room at 614.588, we can’t add Table 1 notation to indicate when and/or where the epidemic is taking place.
What about vaccines for Ebola and other preventive measures? We find 615.372 Vaccines, which has a class-elsewhere note reading, "Class use of specific vaccines with the disease in 614.5, e.g., use of influenza vaccines 614.518." The anticipated literature on Ebola vaccines will thus be classed with Ebola preventive medicine in 614.588.
Scanning the hierarchy above 616.918, we find 616 Diseases, which allows us to recognize that 616.918 is the appropriate class number for Ebola virus disease. Again, Ebola is in standing room there, so we cannot undertake any number building to express a more specific element of the topic. An example of a work on the Ebola virus disease, classed in 616.918, is Tara C. Smith’s Ebola.
What about treatment of the disease? Under 615.5 Therapeutics, we find a scatter class-elsewhere note instructing us to "Class therapies applied to a specific disease or group of diseases with the disease or group of diseases in 616–618, plus notation 06 from table under 616.1–616.9, notation 06 from table under 617, or notation 06 from table under 618.1–618.8, e.g., therapies for cardiovascular diseases 616.106." Thus, even though, for example, general works on immune serums are classed in 615.37 Immunologic drugs and immune serums and general works on antiviral drugs are classed in 615.7924 Antiviral agents, works on their use in treating Ebola are classed in the number for the disease, i.e., 616.918. Because Ebola is in standing room at 616.918 (as mentioned previously), we cannot add 616.1–616.9:06 Therapy or any of its subdivisions (despite the explicit [but only general] instruction to do so).