Three highly contagious COVID subvariants have fueled a 120% increase in COVID cases in LA County from a month ago, public health officials said Thursday.
Among the 3,100 or so new cases each day is NBC4 Investigative reporter Joel Grover, who decided to find out what subvariant infected him.
After coughing for a few days, Grover took a rapid home test, thinking he just had a cold. In under 25 seconds the test showed a positive result.
The positive result was a surprise, since Grover continues to mask up in public places, including in the NBC4 newsroom, and mainly gathers with people only outdoors.
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The good news is, we have great effectiveness at preventing severe illness.
Dr. Saahir Khan, USC Keck Medicine
"Some of the newest subvariants out right now are some of the most transmissible agents I’ve ever encountered," said Dr. Peter Chin-Hong, a top infectious disease expert at UCSF.
Infectious disease experts like Dr. Chin-Hong tell the I-Team these subvariants are more contagious than previous Omicron and Delta variants, but produce symptoms that tend to be milder.
The I-Team's Grover wondered what subvariant he was infected with, so the laboratory at USC's Keck Medical School agreed to analyze, or "sequence," his test sample, using a state-of-the-art method developed by USC's Dr. Ha Youn Lee.
The lab's analysis found Grover was infected with a strain of BA.5, one of the three subvariants infecting most people in LA County; the others are BQ.1 and BQ.1.1--which now account for 55% of cases in the county-- and are in the same family as BA.5.
"We don’t think that these subvariants produce more severe disease than previous variants, but we think that they are more contagious," said infectious disease expert Dr. Saahir Khan of USC Keck Medicine.
"What we’re seeing right now with BA5 and some of the children of BA5 is that the symptoms are generally mild…runny nose, congestion, headache," said Dr. Chin-Hong.
But experts say these newer subvariants are so transmissible it's possible to get infected even outdoors, especially in a crowded gathering, even though outdoor settings remain safer.
"With family outdoor gatherings, especially with family that come from all over, it is possible that you could get infected with these hyper transmissible variants, UCSF's Dr. Chin-Hong told NBC4.
Infectious disease experts say if you're infected, it helps to have been vaccinated and boosted, especially with the latest bivalent booster, which was formulated with BA.5 in mind.
Experts say the fact that the I-Team's Grover had received five shots, including the bivalent booster in October, accounts for his mild symptoms.
"None of these interventions [shots] are 100%. The good news is, we have great effectiveness at preventing severe illness," USC's Dr. Khan told the I-Team.
But beware, doctors tell the I-Team the BA.5 subvariant especially can produce false negatives on home tests.
When Grover began feeling cold-like symptoms ten days ago, the first two home tests he took were negative; the third test was positive.
"BA5 is notorious for causing false negative home testing. The trick is to not stop testing if you have symptoms…do three home tests over 36 hours, or do a PCR test," said Dr. Chin-Hong.
And, keep in mind researchers say you can get COVID more than once, sometimes just a few months apart.
"You can get it again, but you’d probably have very mild symptoms. And the more times you get it, the milder and milder they get," said Dr. Chin-Hong.
LA County Public Health officials worry that the daily case number could go even higher after December 25.
So they're urging people to take precautions this holiday season, including masking up when indoors with others, and trying to have gatherings outdoors whenever possible.
Perhaps most importantly, "If you tested positive for COVID, stay home and away from others," said LA Public Health Director Dr. Barbara Ferrer.
