A new strain of Covid-19, more contagious than previous strains, is now circulating in dozens of countries. Other new strains, such as one first detected in South Africa, will almost certainly emerge. Aside from the challenges these mutations pose to public health, they will also be a test of our moral and political principles. As exhausted as we all are from making stressful judgments throughout this pandemic, we are about to face some of the most difficult trade-offs yet.
Preliminary data indicate that the new strain in the U.K. allows the virus to spread from one person to another more easily. The practical upshot is that even the strict lockdowns of early 2020, such as the one just ordered in the U.K. by Prime Minister Boris Johnson, may not be enough to reverse the spread of the virus.
