Unfortunately, flu incubates about 1-4 days before showing symptoms and you can be infectious while asymptomatic a day or so prior to developing symptoms of your own. So there is definitely a risk.
At least a half dozen people have died in the Chicago area already this season, and the hospital I work for requires all employees with patient contact to be vaccinated; those with medical conditions preventing them from being safely vaccinated have to wear masks when with a patient, regardless of whether either of them is showing symptoms. This is being taken seriously.
Missed the edit: I wrote with the assumption that no one was vaccinated, as I figured that would have been an important thing to mention.