Key Points

More than six months after the first case appeared in the department, the COVID-19 outbreak continues in Mayotte. The peak of the outbreak was observed in early May. The incidence rate, which had then reached its peak (139 cases per 100,000 inhabitants), subsequently declined gradually, falling below the threshold of 50 cases per 100,000 inhabitants by early July. At the same time, there was a steady increase in the testing rate, reflecting a gradual improvement in testing capacity (easier access to testing, increased testing capacity, expanded testing criteria, and more frequent testing campaigns). Since the start of the epidemic, 24,349 people have been tested, representing 9% of Mayotte’s population. Due to the relatively stable and reassuring situation during the southern winter, Mayotte is no longer under a public health emergency.

Epidemiological surveillance remains essential, however, to detect any changes in the epidemic, both in terms of its dynamics and its severity (severe cases and mortality). Santé publique France continues its efforts, in collaboration with the ARS, the CHM, the private laboratory, and all surveillance partners. Consequently, since late August, a deterioration in epidemiological indicators has been observed. The end of the winter break was accompanied by a resurgence of COVID-19 cases. One hundred sixteen cases were detected in week 38 of 2020, corresponding to an incidence of 42 per 100,000 inhabitants. The incidence rate is rising across all age groups except for those over 65. Although it has increased
slightly in recent weeks, the incidence among those under 14 remains well below the average incidence rate.

This situation is notably linked to the increase in the number of clusters occurring in various settings. Since week S34, 11 new clusters have been identified, representing more than one-third of all clusters recorded since the start of the epidemic. These clusters, some of which have led to secondary and tertiary transmissions, have generated 139 cases. Particular attention must be paid to the northern part of the island and to school settings, where nearly half of the new clusters have been identified.

Investigations have shown their limitations in comprehensively identifying contacts during large gatherings (religious ceremonies, evening parties, etc.). The issue of unidentified contacts—some of whom are infected individuals who are unaware of their status—contributes to the persistence of transmission chains across the entire territory. While the incidence has been rising since the start of the school year, the testing rate has been declining. This suggests that the population has been relying less on testing in recent weeks. This phenomenon is part of a broader context of reduced vigilance regarding the epidemic. The lull observed during the winter, combined with the limited severity of the epidemic in a particularly young population, likely contributed to this trend. Indeed, the number of hospitalized cases remains low, even though there has been a resurgence of intensive care admissions for Covid-19-related respiratory distress since the start of the school year.