Figure 3
Representativeness of the dataset of COVID-19 confirmed cases on buses. The daily numbers of (a) all infectious passengers, (b) infectious passengers who are healthcare workers, (c) all infectious individuals in the entire city, and (d) infectious individuals who are healthcare workers in the entire city. For healthcare workers, we highlight an unexpected emergence of a single peak in the daily numbers of infectious individuals within buses and in the entire city, which contrasts to the first and the second waves of COVID-19. We conjecture that the explanation for this behavior may be the lack of Personal Protective Equipment (PPE) in hospitals during the first wave or the herd immunity of healthcare workers during the second wave. (e) The fraction of all infectious passengers. (f) The fraction of infectious passengers who are healthcare workers. These results show that the percentage of infectious passengers with respect to all infectious individuals in Fortaleza was higher than 1% during most of the epidemic period (dashed gray line). All solid lines represent moving averages with windows of 7 days.
