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From The Asian Reporter, V32, #3 (March 7, 2022), page
7.
Is omicron leading us closer to herd immunity
against COVID?
By Victoria Milko
AP Science Writer
AP Illustration by Peter Hamlin
Is omicron leading us closer to herd immunity against
COVID-19?
Experts say it’s not likely that the highly transmissible
variant — or any other variant — will lead to herd immunity.
"Herd immunity is an elusive concept and doesn’t apply to
coronavirus," says Dr. Don Milton at the University of Maryland
School of Public Health.
Herd immunity is when enough of a population is immune to a
virus that it’s hard for the germ to spread to those who aren’t
protected by vaccination or a prior infection.
For example, herd immunity against measles requires about 95%
of a community to be immune. Early hopes of herd immunity
against the coronavirus faded for several reasons.
One is that antibodies developed from available vaccines or
previous infection dwindle with time. While vaccines offer
strong protection against severe illness, waning antibodies mean
it’s still possible to get infected — even for those who are
boosted.
Then there’s the huge variation in vaccinations. In some
low-income countries, less than 5% of the population is
vaccinated. Rich countries are struggling with vaccine
hesitancy. And young children still aren’t eligible in many
places.
As long as the virus spreads, it mutates — helping the virus
survive and giving rise to new variants. Those mutants — such as
omicron — can become better at evading the protection people
have from vaccines or an earlier infection.
Populations are moving toward "herd resistance," where
infections will continue, but people have enough protection that
future spikes won’t be as disruptive to society, Milton says.
Many scientists believe COVID-19 will eventually become like
the flu and cause seasonal outbreaks but not huge surges.
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