There are three ways to stop any disease: Vaccine; prevention, which is not currently available for coronavirus. Cure; anecdotally, several are available but they are only in use in some places, by some doctors, which is a self infliction of sub-optimization. And finally establishing herd immunity.
What is herd immunity?
We reach herd immunity when enough people become immune to the disease so the disease has nowhere to go and dies off. Every person who has had the disease and recovers plus those who had it though remaining asymptomatic contributes to herd immunity.
Herd immunity is reached when a high enough proportion of the population is immune to a disease. At that point new cases are not likely to spread to others. That point varies with different diseases. The important characteristics are the method of transmission and the infectiousness of the disease itself.
Influenza is transmissible in airborne droplets. For it the herd immunity threshold range is from 33%-44% of the population. Measles uses airborne transmission and its threshold range is 92%-95% of the population. Ebola requires transmission through bodily fluids and its threshold range is 33%-60% of the population.
Given the accuracy of modeling for Covid 19 the information may as yet be unreliable. The method of transmission is airborne droplets and the threshold range is 29%-74%. That’s a very wide range.
Watching Sweden
Many are watching Sweden’s response to the coronavirus. Sweden is pursuing a much more normal mitigation strategy. It is practicing social distancing, and communicating prevention techniques but avoiding a national lockdown.
Approximately 20% of Swedes may have gotten the disease with many now immune to the virus. Sweden’s top epidemiologist, Dr. Anders Tegnell expects the nation to achieve herd immunity in several weeks’ time.
Just Asking…
What is absolutely certain is Sweden is not incurring the same level of economic damage America is. The questions are: What will the difference in the death toll be? What will the difference in economic damage be? Will the disease overwhelm either country’s healthcare system?
Does any state have the right to lock down their population without information to demonstrate sufficient lethality? What is sufficient lethality? Is fear alone enough to require forced suppression of civil liberties? Whose fear must it be? Is it limited to diseases or can we suppress civil liberties for fear of guns or snakes or spiders? Should we suspend civil liberties until a cure for death is in place? Is that where we are going? It pretty much feels like it.