Assessment of carbon monoxide poisoning surveillance in the Tanger-Tetouan-Al Hoceima region, Morocco: Insights from a capture-recapture Study

In Morocco, poisoning surveillance is ensured by a vigilance system developed and implemented by the Moroccan Anti-Poison Control Centre (MPCC) since 1980. The aim of this study is to estimate the total number of carbon monoxide poisoning cases reported in the Tanger-Tetouan-Al Hoceima region of Morocco. The study focuses on cases of carbon monoxide poisoning cases identified by the Moroccan Poison Control Centre (MPCC) and those recorded in the registries of provincial hospitals in the study region between 2014 and 2016. The completeness of the surveillance system was assessed using the capture-recapture method. During the study period, the two data sources identified 1,767 cases of carbon monoxide poisoning: 800 cases were reported by the Moroccan Anti-Poison Control Center, and 1,183 cases were recorded in the hospital registers, with 216 duplicate cases. Using the capture-recapture method estimated the total number of cases was estimated to be 4381 (95% CI: 3,930-4,833). The completeness of poisoning surveillance was estimated at 27% based on MPCC data and 18.26% based on hospital registries in the region. The results of this study highlight the limited completeness of poisoning surveillance in the population.