The ARS, the SEM (operator of the public drinking water network), the Metropolitan Authority, and the Rousset
City Hall immediately launched initial environmental investigations. Without
waiting for the results, a bottled water distribution program was set up, first for vulnerable
groups (nursing homes, daycare centers) and then for the entire population.
At the same time, Santé publique France Paca-Corse and the ARS launched epidemiological investigations
. An online questionnaire was distributed on April 17 to
residents and visitors to the town.

To date:

• more than 1,000 people have responded, of whom more than 750 reported symptoms
  ;
• the vast majority (85%) are residents or had visited the town a few
  days before symptoms appeared;
• approximately 90% of those affected reported one or more episodes of diarrhea and/or vomiting
  . Other symptoms such as fatigue, abdominal pain,
  nausea, or fever were also reported.

Although 25 short-term hospitalizations were reported, no severe cases were
identified. Analysis of the epidemiological data indicates that the outbreak peaked on April 14,
followed by a sharp decline in the days that followed. Even though a few cases are still being reported,
the trend observed over the last few days seems to indicate the end of the outbreak.

At this stage, the hypothesis of an origin linked to the drinking water distribution network is
favored, without a clear identification of the cause of the contamination. Environmental investigations
are ongoing.
The latest water analyses are compliant, and close monitoring of water quality has
been implemented.

Pending the results of the latest investigations, all precautions must be
maintained, and the restriction on water use therefore remains in effect.