<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class="StoryBodyCompanionColumn css-1fanzo5" style="margin: 0px auto 1rem; padding: 0px; border: 0px; font-family: -webkit-standard; font-size: 18px; line-height: inherit; vertical-align: baseline; display: flex; flex-direction: row; height: 132px; width: 1200px; color: rgb(51, 51, 51);"><div class="css-53u6y8" style="margin: 0px 0px 0px calc((100% - 600px) / 2); padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; width: 600px; max-width: 600px;"><div style="margin: 0px; padding: 0px; border: 0px; font-family: nyt-imperial, georgia, 'times new roman', times, serif; font-size: 1.25rem; font-style: inherit; font-variant-caps: inherit; line-height: 1.875rem; vertical-align: baseline; width: 600px; max-width: 100%;" class="">If we cannot resume economic activity without causing a resurgence of Covid-19 infections, we face a grim, unpredictable future of opening and closing schools and businesses.</div></div><aside class="css-ew4tgv" aria-label="companion column" style="margin: 0px 0px 0px auto; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; display: flex; width: 210px; -webkit-box-align: center; align-items: center;"></aside></div><div class="StoryBodyCompanionColumn css-1fanzo5" style="margin: 0px auto 1rem; padding: 0px; border: 0px; font-family: -webkit-standard; font-size: 18px; line-height: inherit; vertical-align: baseline; display: flex; flex-direction: row; height: 132px; width: 1200px; color: rgb(51, 51, 51);"><div class="css-53u6y8" style="margin: 0px 0px 0px calc((100% - 600px) / 2); padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; width: 600px; max-width: 600px;"><div style="margin: 0px; padding: 0px; border: 0px; font-family: nyt-imperial, georgia, 'times new roman', times, serif; font-size: 1.25rem; font-style: inherit; font-variant-caps: inherit; line-height: 1.875rem; vertical-align: baseline; width: 600px; max-width: 100%;" class="">We can find a way out of this dilemma by exploiting a key property of the virus: its latent period — the three-day delay on average between the time a person is infected and the time he or she can infect others.</div></div><aside class="css-ew4tgv" aria-label="companion column" style="margin: 0px 0px 0px auto; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; display: flex; width: 210px; -webkit-box-align: center; align-items: center;"></aside></div><div class="StoryBodyCompanionColumn css-1fanzo5" style="margin: 0px auto 1rem; padding: 0px; border: 0px; font-family: -webkit-standard; font-size: 18px; line-height: inherit; vertical-align: baseline; display: flex; flex-direction: row; height: 165px; width: 1200px; color: rgb(51, 51, 51);"><div class="css-53u6y8" style="margin: 0px 0px 0px calc((100% - 600px) / 2); padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; width: 600px; max-width: 600px;"></div></div><a href="https://www.nytimes.com/2020/05/11/opinion/coronavirus-reopen.html?action=click&module=Opinion&pgtype=Homepage" class="">https://www.nytimes.com/2020/05/11/opinion/coronavirus-reopen.html?action=click&module=Opinion&pgtype=Homepage</a></body></html>