I'm in the #4 COVID hotspot of the world...nearby town still having cases. But our hospital has ZERO right now. What does that tell you? Herd immunity. I personally know people of all ages that have had it, the kids are friends of my kids, the adults are customers, they recovered and live normal lives. My wife knows patients that have died, probably why she's so scared. But health is about more than masks, it's what you eat, what you drink, how you live...every death is not 'preventable.' I would argue it's more personal decisions about lifestyle than anything.
What will it take to achieve herd immunity with SARS-CoV-2?
As with any other infection, there are two ways to achieve herd immunity: A large proportion of the population either gets infected or gets a protective vaccine.
- In the worst case (for example, if we do not perform physical distancing or enact other measures to slow the spread of SARS-CoV-2), the virus can infect this many people in a matter of a few months. This would overwhelm our hospitals and lead to high death rates.
- In the best case, we maintain current levels of infection—or even reduce these levels—until a vaccine becomes available. This will take concerted effort on the part of the entire population, with some level of continued physical distancing for an extended period, likely a year or longer, before a highly effective vaccine can be developed, tested, and mass produced.
- The most likely case is somewhere in the middle, where infection rates rise and fall over time; we may relax social distancing measures when numbers of infections fall, and then may need to re-implement these measures as numbers increase again. Prolonged effort will be required to prevent major outbreaks until a vaccine is developed. Even then, SARS-CoV-2 could still infect children before they can be vaccinated or adults after their immunity wanes. But it is unlikely in the long term to have the explosive spread that we are seeing right now because much of the population will be immune in the future.
Why is getting infected with SARS-CoV-2 to “get it over with” not a good idea?
With some other diseases, such as chickenpox before the varicella vaccine was developed, people sometimes exposed themselves intentionally as a way of achieving immunity. For less severe diseases, this approach might be reasonable. But the situation for SARS-CoV-2 is very different: COVID-19 carries a much higher risk of severe disease and even death.
The death rate for COVID-19 is unknown, but
current data suggest it is 10 times higher than
for the flu. It’s higher still among vulnerable groups like the elderly and people with weakened immune systems. Even if the same number of people ultimately get infected with SARS-CoV-2, it’s best to space those infections over time to avoid overwhelming our doctors and hospitals. Quicker is not always better, as we have seen in previous epidemics with high mortality rates, such as the
1918 Flu pandemic.
https://www.jhsph.edu/covid-19/articles/achieving-herd-immunity-with-covid19.html
We have never achieved herd immunity without a vaccine, Zricky.. Sorry ol' chap.