CHELSEA, Mass. — After months as a high-risk red community, Chelsea partially threw off the shackles of Covid in mid-February.
That’s when the city of 40,000 slipped into the yellow, moderate zone. And for the next six weeks, cases here kept dropping.
And then came April.
While the city remains yellow, cases rose in each of the last two weeks. While the percent testing positive is just slightly above the state average (2.57% vs. 2.54%) in Chelsea, it’s the highest proportion in weeks.
And there’s a likely reason why Chelsea, along with more than 200 other Massachusetts communities, saw a rise in Covid cases last week, according to the Department of Public Health.
“We know that most of the Covid in Massachusetts is related to the B.1.1.7 variant,” said Brian Hollenbeck, MD, Chief Medical Officer and Chief, Infectious Disease at New England Baptist Hospital. “We’re doing a lot of variant testing and sampling across the state. Really at this point, there’s no neighborhood that’s unaffected by the variant.”
One place B.1.1.7 is showing up for sure is in wastewater samples from towns served by the MWRA.
“Wastewater sampling is going to give us a population look at certain neighborhoods or certain areas that may be more under pressure from Covid,” Hollenbeck said. “So we can see certain pockets of increased spread that may go beyond people presenting themselves for testing.”
Keeping in mind many Covid infections still present with few or any symptoms -- even though viral residues may be excreted from host gastrointestinal tracts.
B.1.1.7 is much more transmissible than the previously circulating variant -- and it is also considered more pathogenic.
“A greater percentage of individuals infected with that variant end up being hospitalized,” said James Musser, MD, Chair of the Department of Pathology and Genomic Medicine at Houston Methodist Hospital in Texas.
Could the variant get any worse? Actually, it has -- but only in small numbers.
“Generating mutants, evolutionary genetics, that’s a common thing that every pathogen does,” Musser said. “And it just depends on the particular pressures that are put on the pathogen.”
One pressure B.1.1.7 has to deal with: annihilation by antibodies.
But it may be finding a way around that.
Recently, U.K. researchers discovered a few B.1.1.7 samples that also contained the same mutation found on such vaccine-stubborn variants as P.1.
It is known as E484K.
“These variants have a specific mutation within the genome of the virus that changes the way that the spike protein looks to our immune system,” Hollenbeck said.
Could this mutant on top of a mutant become dominant? Possibly... but it’s not looking that way, at the moment.
“I don’t see that coming in high frequency in the near future,” Musser said. “I think it’s always possible we could have a small number of additional cases.”
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