Sonoma County and Bay Area public health experts weigh in on omicron variant
Local public health and infectious disease experts on Friday urged both calm and vigilance amid escalating global concerns about a new COVID-19 virus mutation that some experts fear could be more transmissible than existing strains.
Though little is known about the new coronavirus variant, dubbed “omicron” by the World Health Organization on Friday, global health officials said they were particularly concerned about the large number of mutations in its spike protein, which plays a key role in virus transmission.
WHO officials said preliminary evidence suggests an increased risk of reinfection with the omicron variant, compared to other strains. The number of omicron variant cases appears to be increasing in almost all provinces in the country of South Africa. Health officials there first reported the variant to WHO on Nov. 24.
Dr. Sundari Mase, Sonoma County’s health officer, said until more is learned about the variant there is little cause for local alarm, though she urged continued vigilance and adherence to existing pandemic precautions. State and local epidemiologists are on the lookout for the variant, she said.
“The state is aware of the variant and is tracking it, and at this time there is no cause for concern – we haven’t seen that particular variant here at this time,” Mase said. “Since we don’t really have a shortage of vaccine, if you haven’t got a booster shot and are eligible this would be a good time to get that.”
The county’s public health lab is equipped with genetic sequencing equipment that will be able to detect the omicron variant. The delta variant continues to be the most prevalent of genetically sequenced mutations, at 75% of 2,185 genotyping results as of Nov. 15.
The state Department of Public Health conducts regular genotyping surveillance, while local health officials will be looking for tell-tale signs that a more transmissible or vaccine resistant strain has arrived. Mase said that includes sudden spikes in new COVID-19 cases, as well as in increase in breakthrough among vaccinated residents.
“We’ll definitely be looking for this mutation in Sonoma County,” she said.
Dr. John Swartzberg, a UC Berkeley infectious disease expert, said one of the most troubling aspects of the new variant is the sheer number of mutations to the spike protein, which allows these viruses to penetrate host cells and cause infection. He said some 32 such mutations have been detected with the omicron variant, compared to the delta strain, which has nine mutations on its spike protein.
But again, he said, its still not clear whether this makes the omicron variant more troublesome, including whether it can evade existing COVID-19 vaccines.
Dr. Anthony Fauci, the nation's top infectious disease expert, told CNN Friday that the presence of specific mutations in the new variant “can give you a hint or a prediction that it might evade the immune response.” He said U.S. infectious disease teams will be conducting tests to determine the variant’s resistance to vaccines.
News of the new COVID-19 variant sent chills across the globe, with markets plunging sharply and many countries quickly announcing restrictions on travel from southern Africa. United States officials on Friday afternoon restricted travel from South Africa, Botswana, Zimbabwe, Namibia, Lesotho, Eswatini, Mozambique and Malawi. The U.S. ban goes into effect on Monday.
Such restrictions, though probably politically necessary, are not likely to halt the spread of the new variant, which has already been detected in Hong Kong, Israel and Belgium, said Swartzberg.
“Closing borders, in the long run, is not going to help much,” Swartzberg said. “It may slow up transmission but ultimately it’s not going to stop this from spreading around the world.”
Swartzberg reiterated that not much is known about the new variant and many more tests are needed before it can be determined whether the variant is going to “outcompete“ other strains of COVID-19, particularly the delta variant. But preliminary data shows the omicron variant is spreading much more rapidly than other strains in South Africa, he said.
“Delta was 70% more transmissible than the ancestral strain and this one, according to preliminary data, is maybe twice as transmissible as delta,” Swartzberg said.
The UC Berkeley expert said the good news is that current PCR diagnostic tests for COVID-19 may actually detect the variant, making it possible to “flag” the presence of the mutation while more complex genetic sequencing is being conducted.
Both Swartzberg and Mase said it is not yet known if the omicron variant is more virulent and causes more severe illness than existing strains of COVID-19.
But they said the appearance of a new variant is yet another reminder that the pandemic is not over and people need to continue with pandemic-era practices such as masking indoors and avoiding crowds of people if unvaccinated.
You can reach Staff Writer Martin Espinoza at 707-521-5213 or martin.espinoza@pressdemocrat.com. On Twitter @pressreno.
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