Trends and Epidemiology of Ciguatera in Vanuatu, 2015-2024

Ciguatera fish poisoning is a pervasive seafood-borne illness across the Pacific; however, surveillance remains challenging, and data are limited. This study explores how combining epidemiological data with indigenous traditional knowledge, derived from community surveys, can improve the understanding and management of ciguatera on Ambae Island in Vanuatu. A mixed-methods approach was employed, integrating a review of health facility records with community survey data. Data were collected from seven health facilities serving the three area councils (East, North, and West) of Ambae Island based on the period from 2015 to 2024. The results show that CFP cases peaked in April, May, October, and November, with the highest annual case numbers recorded in 2017 and 2024. Nduindui and Walaha Health Centres reported the highest number of cases, followed by Lolopuepue Health Centre. According to area councils, West Ambae recorded the highest incidence rates, approximately 937 cases per 100,000 people per month and 765 cases per 100,000 people per year, compared to lower rates in the North and East Area Councils. The community survey revealed that 85% of the 97 respondents experienced symptoms consistent with ciguatera. Additionally, 25 local plant species were identified as traditional treatments for CFP symptoms across the three area councils. Expanding comparative surveillance across other islands in Vanuatu and the Pacific could strengthen CFP management and public health responses.