The value of decreasing the duration of the infectious period of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection

Abstract

Finding medications or vaccines that may decrease the infectious period of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) could potentially reduce transmission in the broader population. We developed a computational model of the U.S. simulating the spread of SARS-CoV-2 and the potential clinical and economic impact of reducing the infectious period duration. Simulation experiments found that reducing the average infectious period duration could avert a median of 442,852 [treating 25% of symptomatic cases, reducing by 0.5 days, reproductive number (R0) 3.5, and starting treatment when 15% of the population has been exposed] to 44.4 million SARS-CoV-2 cases (treating 75% of all infected cases, reducing by 3.5 days, R0 2.0). With R0 2.5, reducing the average infectious period duration by 0.5 days for 25% of symptomatic cases averted 1.4 million cases and 99,398 hospitalizations; increasing to 75% of symptomatic cases averted 2.8 million cases. At $500/person, treating 25% of symptomatic cases saved $209.5 billion (societal perspective). Further reducing the average infectious period duration by 3.5 days averted 7.4 million cases (treating 25% of symptomatic cases). Expanding treatment to 75% of all infected cases, including asymptomatic infections (R0 2.5), averted 35.9 million cases and 4 million hospitalizations, saving $48.8 billion (societal perspective and starting treatment after 5% of the population has been exposed). Our study quantifies the potential effects of reducing the SARS-CoV-2 infectious period duration.

Fig 1

Percent reduction in SARS-COV-2 cases at the epidemic peak for various reductions in the average infectious period duration when treating various proportions of symptomatic and all infected cases with a reproductive rate (R₀) of A) 2.0, when starting treatment after 5% of the population has been exposed, B) 2.0, when starting treatment after 15% of the population has been exposed, C) 2.5, when starting treatment after 5% of the population has been exposed, D) 2.5, when starting treatment after 15% of the population has been exposed, E) 3.5, when starting treatment after 5% of the population has been exposed, and F) 3.5, when starting treatment after 15% of the population has been exposed.

Fig 2

Median number of SARS-CoV-2 cases averted by reducing the average infectious period duration when treating various proportions of symptomatic and all infected cases when A) starting treatment after 5% of the population has been exposed with an R₀ of 2.5, B) starting treatment after 15% of the population has been exposed with an R₀ of 2.5, C) starting treatment after 5% of the population has been exposed with an R₀ of 3.5, and D) starting treatment after 15% of the population has been exposed with an R₀ of 3.5.

Fig 3

Median number of A) hospitalizations averted, and B) ICU admissions averted, by reducing the average infectious period duration when treating various proportions of symptomatic and all infected cases when starting treatment after 15% of the population has been exposed with an R₀ of 2.5 and 3.5.