erdiscus, might have extended biogeographical ranges, induced by human activity. For example, benthic dinoflagellates are likely to be able to colonize previously unoccupied locations through transport in ship ballast . Certain species of Gambierdiscus has now been found to be highly ciguatoxic compared to the other species , and blooms of these species are likely to contribute most to ciguatera risk.
Given changes in global climate patterns, increased degradation of coastal marine environments through coastal development and land run-off, and increased exploitation of coastal marine resources, the incidence of ciguatera cases is predicted to continue to increase in the future , . Therefore, we hypothesized that ciguatera incidence is an increasing human health and ecological concern across the PICTs. To test this hypothesis, we report on changes in ciguatera incidence across the Pacific, and the social consequences of changing ciguatera incidence by comparing two 11 year periods of data: 1973–1983 vs 1998–2008.
The Secretariat of the Pacific Community, the Institut Louis Malarde (Tahiti), the Institut Louis Pasteur (New Caledonia), and Institute for Research and Development (IRD) organized a Ciguatera workshop held in Noumea, October 2008. At this workshop, many island nation delegates declared a need for the ciguatera concern to be better addressed. To start to understand the current extent and nature of the ciguatera problem, we distributed a questionnaire to all PICTs (Supporting information S1). Ciguatera records used in this study are housed in each PICTs government health institution (Ministries and Departments of Health and Public Health).
To obtain the ciguatera records for the period of 1998 to 2008, we first contacted the Secretariat of the Pacific Community (SPC), Division of Fisheries, Aquaculture and Marine Ecosystems (FAME) to obtain the list of institutions responsible for maintaining ciguatera records within PICTs. We considered these repositories were comaparable to the data collection repositories used in the Lewis et al. study . The questionnaire (Supporting Information S1) was sent by email to the institutions in October 2009. Updates on the returning of the questionnaires were sent to PICTs on four occasions over the period, and questionnaires were returned from the PICTs up until April 2010.
The questionnaire was developed by the co-authors in collaboration with the PICTs. The questionnaire included questions and definitions from prior ciguatera studies to provide consistency of data gathering and allow comparison across studies. The 3 key sections of the questionnaire collected information on: 1) Temporal incidence of ciguatera; 2) Environmental disturbance, to examine if coral reef condition and occurrence of coral bleaching and cyclones might influence ciguatera incidence (these data were considered purely speculative on the part of the respondent); and 3) Social consequences of ciguatera including changing diet and associated medical conditions, proactive and reactive management of ciguatera, and the desire for external assistance in response to ciguatera.
1) Temporal incidence of ciguatera.
To determine whether the per capita incidence of ciguatera has increased significantly, as hypothesized, comparisons are made between the data from this study (1998–2008) and the work of Lewis  who reported on the epidemiology of ciguatera in the Pacific for the years 1973 to 1983. We tested for significant change in ciguatera incidence across PICTs by comparing mean annual incidence (per 100,000 people) within each PICT in each time period using a paired t-test, controlling for missing ciguatera values. We tested for overall change in ciguatera incidence using annual incidence (per 100,000 people) means across all PICTS for the two time periods using a independent-sample t-test and linear regression analysis, controlling for missing ciguatera values. All total incidence and incidence mean values were normalized prior to analysis using a natural log transformation. We also present the rates ratio (1998–2008