This study had three limitations of note. First, detailed information about the ventilation systems and size of the restaurant are not available , so fluid dynamics analyses could not be performed. Therefore, the possibility of a long-range airborne route was not evaluated, and its relative importance versus the fomite route could not be accurately determined . Second, due to the limited understanding of some of the parameters of norovirus transmission, some parameters in the model, such as the rate of transfer from hands to porous surfaces (Table S2), were estimated from those of other viruses or even bacteria. This might have reduced the accuracy of the results. Third, given the lack of real-time observation data, the model included many assumptions about the common surfaces and the actual behaviors and movements of the guests and waiters (Table S4), which might have affected the infection risk distributions shown in Figure 2 and Figure S1. In general, more detailed outbreak information, laboratory measurements and human behavioral observations would be required to provide a more accurate analysis of norovirus transmission in this outbreak.