Epidemiological Situation

Following an unusually low level of dengue virus circulation in 2017, including during the southern hemisphere winter, the number of dengue cases has been increasing since the beginning of 2018. An intensification of viral circulation has been observed each week since January 29. During the past week (April 2–8), 237 locally acquired cases and 1 case imported from Mauritius were reported, bringing the total number of locally acquired dengue cases reported in Réunion in 2018 to 992. Since the beginning of 2017, a total of 1,086 locally acquired cases and 10 imported cases have been confirmed.

The cases reported last week are mainly located:

• in the west (St-Paul, Gare routière, and Etang; 53 cases), Bois de Nèfles and La Plaine (47 cases), St-Gilles-les-Bains (16 cases), St-Gilles-les-Hauts (12 cases), La Saline (8 cases), La Possession (7 cases), Le Port (20 cases), and St-Leu (6 cases).

• in the south in St-Pierre (19 cases) and Ravine des Cabris (26 cases)

During the week, isolated cases were also identified; they reside in Saint-Denis/Ste Clotilde (1 case), Sainte-Marie (1 case), Saint Paul (Le Guillaume, 1 case), Etang-Salé (1 case), Saint-Louis (3 cases), Le Tampon (3 cases), and Saint-Joseph (3 cases). Ongoing investigations will help identify their presumed place of infection.

Since early 2017, the predominant serotype has been DENV-2 (534 genotypes). The other viruses identified are DENV-1 (4 genotypes) and DENV-4 (1 genotype), primarily in imported cases in 2017.