Which factor is crucial in assessing the severity of a bed bug infestation?

In assessing the severity of a bed bug infestation, visual inspection findings play a critical role. This includes identifying the presence of live bugs, their eggs, shed skins, and droppings, which provide concrete evidence of the infestation. Visual inspections allow professionals to determine not only the presence of bed bugs but also their population density and potential hiding spots.

This direct observation can help in assessing the extent of the infestation and inform appropriate control measures. Visual evidence is key for making decisions regarding treatment and helps in monitoring the effectiveness of control efforts over time. While the number of bites reported, the speed of spread, and the location of the infestation can provide valuable information, they do not offer as definitive a measure of the infestation's severity as visual inspection findings do.