Key Points

Chikungunya

• 70 cases of chikungunya were reported in Week 12 in Mayotte, representing a 37% decrease compared to Week 11 (111 cases), although these data have not yet been finalized;

• Viral circulation remains active throughout the territory, requiring increased vigilance;

• Transmission could continue or intensify, given current weather conditions that favor mosquito proliferation.

Smallpox B (Mpox)

• Three new confirmed cases of Mpox have been identified in the territory after four weeks without any reports, bringing the total number of cases since the beginning of the year to 13 (including 10 locally acquired cases and 3 imported cases). This indicates limited but persistent local transmission, requiring continued surveillance of this disease;

• The three new cases identified in S12 are linked to intra-family transmission;

• Geographic distribution: of the 13 cases recorded since the beginning of the year, nearly all (10 out of 13) are located in the municipalities of Bouéni and Mamoudzou (5 cases each).

Bronchiolitis

• Since the epidemic peak in S09-2026, a decrease in bronchiolitis activity has been observed, with 18 positive samples in S12 (positivity rate: 30.5%), but the region remains in the epidemic phase.

• Emergency department activity remains high among infants, with 24 visits in S12, including 11 hospitalizations.

• Bronchiolitis accounted for 31% of pediatric emergency department activity in S12-2026.