2/ For those who don't know, herd immunity is when a large portion of the population has immunity to an infectious disease. This forms a "cushion" to stop the infection from reaching people who do not have immunity. @JohnsHopkinsSPH's quick definition: jhsph.edu/covid-19/artic…
3/ While herd immunity might be achieved through vaccination, herd immunity through "getting it over with," achieved through allowing lots of people to get infected, is NOT a good public health strategy. coronavirus.jhu.edu/from-our-exper…
Here are 4 reasons why:
4/
Reason 1: Many people will still get infected even if 70% are recovered.
This is because Covid infects fairly frequently: Its “R-naught (R0),” or the average number of people a person with #COVIDー19 will infect, is between 2-3 (compared to the flu at around 1.3).
5/
Reason 2: Many people would die.
The percentage of people who die from COVID-19 is, depending on the model, 0.5-1.1%. Even so, if we estimate that 70% of the population must become infected to reach immunity, that would mean a lot of deaths. npr.org/2020/04/24/844…
6/
Reason 3: It would overwhelm our #healthcare system 🏥
For example, in New York, it is anticipated that perhaps 20% have been infected and recovered.
Even with only ~1 in 5 people infected, our hospitals were overwhelmed and many people died.
7/ Reason 4: We don’t know enough about immunity in COVID-19
While we don’t have evidence that people can be reinfected with COVID-19, we don’t know how long people would be (if they are) immune.
We also don’t know if people can become reinfected but be asymptomatic.
8/ While it is unlikely that we don’t mount sufficient immune response (like in HIV) or that the virus mutates quickly, rendering our old response inadequate (like with the seasonal flu virus)..
**We still need long-term data to be confident that infection confers immunity!!
1/ Q: Has almost everyone been infected with COVID by now?
A: Recent estimates suggest around 58% of the population in the US and over 70% in England have been previously infected, with BIG increases during the Omicron wave.
3/ ➡️ During the Omicron wave from December 2021-February 2022, this estimate increased from 33% to 58%.
➡️ Rates vary a lot by age, ranging from 33.2% for those over age 65 to 75% for those under age 18.
2/ Not likely. If your kids are suddenly getting sick a lot, this is likely due to “catching up” on exposures rather than a weakened immune system.
3/ Many families w/ young kids have been hunkered down for the better part of 2 years– a good % of a young child’s entire life. While isolation had *many* downsides, we can agree that not having to suction snot out of infant noses or clean up norovirus puke was a happy upside.
1/ Q: Are cases peaking? That means it’s all downhill from here, right?
A: Sort of…. Remember that even if cases come down as quickly as they rise, there will be as many cases *after* the peak as before (think area under the curve).
2/ ➡️ And if the downward slope is *slower* than the rise, we will see *more* cases during the decline from a surge.
3/ Burning fast could be a silver lining of super transmissible #Omicron. Cases rose & fell quickly in S. Africa (w/ hospitalizations & deaths still lagging). The UK appears to have turned the Omicron corner. Many US states appear past their peak in cases, w/ regional variation:
Unfortunately, this includes New Year’s Eve plans. The perfect storm of a new variant & holiday get-togethers is hitting communities & health care w/ FORCE! Testing is in short supply.
3/ Health care is under extreme pressure with surging cases. If you can avoid even one additional contact, you are helping. This is a temporary and urgent request (from a health care provider).