Community waterborne outbreak linked to a firefighting response during the COVID-19 emergency.

Background: On 6 March 2020, a big fire in a village forced the firefighters to draw water simultaneously from many sources, including the Adige river. From 9 March, an increasing number of inhabitants reported gastrointestinal symptoms. We describe the outbreak and the challenges linked to the concurrent COVID-19 spread.

Methods: Residents with enteric symptoms and their relatives were interviewed and samples from some of the patients and public water pipelines were tested for enteric pathogens with microbiological and molecular methods.

Results: By 20 March, 182 people reported symptoms and 131 met the case definition. Norovirus GI/GII and other pathogens were found in human and water samples.

Conclusions: Contamination of the public water network with sewage-contaminated river water through the firefighters pressurized water tank was the suspected source of the outbreak. The investigation was partly hampered due to the SARS-CoV-2 emergency. Control measures included avoiding tap water, alternative water supplies and chlorination of public water.