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. 2021 Aug 31:M21-2965. doi: 10.7326/M21-2965

Figure 1. Cumulative infections with 50% vaccination coverage and testing targeted to the unvaccinated population alone.

Figure 1. Cumulative infections with 50% vaccination coverage and testing targeted to the unvaccinated population alone. The figure illustrates the findings of the model under baseline input data assumptions, assuming 50% vaccination coverage. The curves report the expected cumulative infections in the population over a 120-day semester (y-axis) under alternative frequencies of routine, asymptomatic testing of unvaccinated persons (ranging from no testing to testing every day). The R* is inversely related to the aggressiveness of NPI measures, such as masking and distancing. In the absence of any testing (purple curve), cumulative infections may be held below 5% of the campus population (horizontal red dashed line) if R* is < 1.5 (that is, implementation of aggressive NPIs). With testing twice a week (yellow curve), that level of cumulative infections could be achieved at R* values of < 3.5; with daily testing (blue curve), it could be achieved at R* values of < 5.25. NPI = nonpharmaceutical intervention; R* = on-campus, effective reproduction number.

The figure illustrates the findings of the model under baseline input data assumptions, assuming 50% vaccination coverage. The curves report the expected cumulative infections in the population over a 120-day semester (y-axis) under alternative frequencies of routine, asymptomatic testing of unvaccinated persons (ranging from no testing to testing every day). The R* is inversely related to the aggressiveness of NPI measures, such as masking and distancing. In the absence of any testing (purple curve), cumulative infections may be held below 5% of the campus population (horizontal red dashed line) if R* is < 1.5 (that is, implementation of aggressive NPIs). With testing twice a week (yellow curve), that level of cumulative infections could be achieved at R* values of < 3.5; with daily testing (blue curve), it could be achieved at R* values of < 5.25. NPI = nonpharmaceutical intervention; R* = on-campus, effective reproduction number.