A
never-before-seen COVID-19 variant has been identified in Humboldt
County, but Public Health officials say current evidence suggests it
was contained to a single outbreak and there is no indication it has
spread to the broader community.
In
late January, Humboldt County Public Health submitted dozens of
samples from individuals who tested positive for COVID-19 at the
Granada Rehabilitation and Wellness Facility, along with dozens of
random samples from the Humboldt County Public Health Lab (PHL), for
routine genomic surveillance. Genomic sequencing of the samples was
conducted by Chan Zuckerberg Biohub (CZ Biohub), a nonprofit medical
research organization that has been responsible for about 45% of the
genomic surveillance in California.
CZ
Biohub determined that 16 of those samples had the same mutation of
the virus’s spike protein at the N501Y position, which is common
among other COVID-19 variants, and Public Health linked all 16 back
to the Granada facility. Lab studies suggest that this mutation makes
the virus “sticky” or easier for the virus to attach to a cell’s
receptors, which could result in a higher rate of transmission.
Humboldt
County Health Officer Dr. Ian Hoffman said that it appears the
mutation occurred within the Granada facility as the virus spread
among staff and residents. “There is no evidence to suggest that
this variant was brought in from outside of Granada, and data
provided by CZ Biohub indicates that it has not been seen elsewhere
in Humboldt County,” he said. “The good news is there has been no
evidence either through genetic testing or contact investigations to
indicate the variant spread into the broader community.”
Senior
Biosecurity Fellow at CZ Biohub Dr. Patrick Ayscue said, “Mutation
is a natural feature of viruses, so it is not unexpected that we will
see variants occasionally arise in outbreaks.” Dr. Ayscue went on
to say, “What is pretty remarkable here is Humboldt County Public
Health was in a position to identify a new and potentially dangerous
variant, contain it and successfully stop it before it had the
opportunity to spread more broadly. It’s really a credit to the
hard work of local public health and their partners.”
The
Humboldt County PHL has been collaborating with CZ Biohub since June
2020, and the nonprofit has sequenced more than 650 samples from
Humboldt County, accounting for approximately 22% of total cases. PHL
Laboratory Manager Dr. Jeremy Corrigan said, “After we package and
send the samples, our teams work together to analyze the sequencing
data and identify any variants of concern. Sequencing also provides a
measure of quality control because we can monitor for mutations that
could impact the effectiveness of the PCR test we utilize,”
referring to the polymerase chain reaction test used by the PHL. Dr.
Corrigan noted that these kinds of partnerships are a great
opportunity to leverage expertise and resources to better understand
local COVID-19 conditions.
Dr.
Hoffman described the outbreak at Granada as heartbreaking for
residents, their families and caregivers as well as the community at
large. Identifying this variant, he said, offers a better
understanding of why the virus was able to spread through the
facility so quickly. “Genomic sequencing is a tool we’ll continue
to use to help us monitor for and contain variants before they become
a problem,” he said.
With
variants of concern on the rise around the world and here in
California, Dr. Hoffman said, prevention measures are vital to
keeping the spread of COVID-19 in check. “Please continue to wear a
mask when in public, maintain physical distance and wash your hands
regularly.”
Read
more about CZ Biohub’s genomic sequencing at czbiohub.org.
For
the most recent COVID-19 information, visit cdc.gov
or cdph.ca.gov.
Local information is available at humboldtgov.org
or during business hours by contacting covidinfo@co.humboldt.ca.us
or calling 707-441-5000.