On Thursday, the Yosemite National Park reported that 170 people had experienced a gastrointestinal illness, and two of them have been confirmed to be a norovirus.
Cruise ship passengers aboard the Marella Explorer 2 reported feeling unwell during their vacation in the Mediterranean Sea.
"They are hand-cleaning every single knob on the climbing wall," one passenger said.
Passengers and sympathizers took to social media to vent their frustrations.
A norovirus outbreak has spread across evacuation shelters for the Camp Fire in California as smoke decreases the air quality to hazardous.
The highly contagious virus sent more than 30 people, most of whom were children, to the hospital.
Holland America was hit especially hard in 2017.