"The development of covid-19 vaccines was a scientific triumph. Converting it
into medical benefits has required getting shots into the arms of as many
people as possible, a process fraught with political and logistical hurdles.
Nonetheless, a new study finds that jabs cut the disease’s death toll by 63%
during their first year.
To calculate the number of lives saved by vaccines, researchers at Imperial
College London needed to estimate how many people would have died without the
jabs. They simulated this scenario using an epidemiological model, which
calculates the shares of the population that are susceptible to a disease; get
exposed; get infected; die or recover; and are vulnerable to reinfection. Each
of these rates depends on factors like the transmissibility and severity of the
pathogen, how much people interact with each other, demography, health-care
quality and, crucially, vaccination.
Such models can simulate any disease. The authors customised theirs for covid
by finding the mix of impacts of these variables that yielded the best
predictions of deaths in each country in each week. Because official tallies
tend to undercount mortality caused by covid, the study relied on The
Economist’s model of excess deaths, which estimates how many more people have
died of all causes during the pandemic than normally would have.
The authors then used this model to predict how many additional deaths would
have occurred during the year starting on December 8th 2020—the day of the
first jab—if no vaccines had been given, but all other factors remained the
same. Excluding countries with tiny populations and China, where our
excess-mortality figures are highly uncertain, the answer was 19.1m-20.4m, 170%
more than our estimate of the actual death toll during this period."
Via Future Crunch
issue 189: https://futurecrunch.com/
*** Xanni ***
Chief Scientist, Xanadu
Partner, Glass Wings
Manager, Serious Cybernetics