Key Points

Surveillance system for 2021, May 1 through November 30

Surveillance for chikungunya, dengue, and Zika relies on an enhanced surveillance system during the active season of the Aedes albopictus “tiger” mosquito, estimated to be from May 1 to November 30.

Upon receiving any positive laboratory result for one of these three diseases, clinicians and/or laboratories are required to immediately report it to the ARS by any appropriate means (flowchart below) using the clinical information form accompanying the specimen or the appropriate Cerfa notification form.

The reporting of a positive biological result immediately triggers epidemiological investigations. These aim to determine the case’s period of exposure and viremia, as well as to identify the various locations visited and movements during this period. Depending on the results of the investigation, appropriate entomological investigations and vector control measures (VCM) are carried out, including the destruction of larval breeding sites and, if necessary, targeted adulticide or larvicide treatments within a 150- to 200-meter radius of the locations frequented by the cases during the viremia period.

Therefore, immediate reporting of any confirmed case to the ARS is recommended in order to promptly initiate mosquito control operations if necessary, thereby reducing the risk of secondary indigenous cases occurring among contacts of cases returning infected from an endemic area.

As of May 17, 2021, two imported cases of dengue fever have been reported in Occitanie.