WASHINGTON, United States (AP) — 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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Earlier AP article related with Omicron – FEB 9, 2022
Can you get long COVID after an infection with omicron?
It’s too early to know for sure, but many doctors believe it’s possible to have long-term effects from the omicron variant of the virus.
Long COVID is usually diagnosed many weeks after a bout with COVID-19. Any long-lasting effects typically appear about 90 days after symptoms of the initial infection go away, Maria Van Kerkhove of the World Health Organization said this week.
Overall, some estimates suggest more than a third of COVID-19 survivors will develop some symptoms of long COVID. Symptoms include fatigue, brain fog, shortness of breath, anxiety and other problems. The lingering illness is more likely if you’ve been hospitalized with COVID-19, but research shows it can happen even after a mild infection.
Omicron began its race around the world late last year. The variant generally causes milder illness than the delta version of the coronavirus, but has still overwhelmed hospitals.
Van Kerkhove said she hasn’t seen any research indicating that the portion of COVID-19 survivors who get long COVID will change with the omicron variant.
Dr. Linda Geng of Stanford University, who co-directs one of the many clinics specializing in long COVID, said that though she can’t say for sure, a new wave of patients is likely.
“We have to be very cautious and very careful and prepared,” Geng said.
In the meantime, scientists are racing to figure out what’s behind the mysterious condition. Some theories? It may be an autoimmune disorder. Tiny microclots may be causing the disabling symptoms. Or perhaps latent viruses in the body have been reactivated.
Scientists are also looking at whether vaccines could be part of the answer. A Yale University team is studying the possibility that vaccination might reduce long COVID symptoms. And two other studies offer early evidence that being vaccinated before getting COVID-19 could help prevent the lingering illness or at least reduce its severity.
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Newsroom | theworldmail.co.uk
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