covid vaccine san diego
A health care worker at the Sharp Healthcare vaccination site in Chula Vista in 2021. / Photo by Adriana Heldiz

New COVID-19 cases seemed to be declining in recent days. That trend didn’t hold. 

San Diego County reported more than 1,600 new positive COVID-19 tests on both Tuesday and Wednesday, bringing the numbers back up to the mid-June surge level.

There were also 10 new deaths and 24 new COVID-19 hospitalizations just between Sunday and Wednesday. 

The county’s dashboard shows 83.7 percent of eligible county residents are fully vaccinated and 94.6 percent have at least one dose. Yet only 57.3 percent of eligible people are boosted — and that’s putting the county at a greater risk of COVID-19 reinfections and new variants. 

Eric Topol, the founder and director of the Scripps Research Translational Institute, said in a tweet that the highly transmissible omicron variant now accounts for 35 percent of new cases in the United States. In San Diego County, omicron variants account for 99 percent of confirmed cases from Jan. 1 to June 17. 

Citing a Centers for Disease Control and Prevention analysis, Topol said that new omicron variants BA.4 and BA.5 allow for a greater risk of reinfections, which means someone was infected, recovered, then later became infected again. Before omicron, the chance of reinfection was less than one percent.

“Reinfections carry substantial risk, as shown in this new analysis, so please keep your guard up,” Topol tweeted.

This is because being infected from BA.1 omicron is not protecting people from new variants that look very different. Topol told KPBS these new variants are “the most immune-invasive and transmissible of the whole pandemic.” 

The new variants are not yet dominant, but when they get to 70-80 percent of cases in the county, we’ll likely see a jump in hospitalizations, Topol said.

CDC research published in April 2022 found that in this omicron-predominant period, vaccine effectiveness against reinfections leading to hospitalizations was about 35 percent after a second dose but about 68 percent after a booster. The booster has also shown some effectiveness against the new omicron variants Topol mentioned.

The County of San Diego published a statement on Thursday “strongly” recommending vaccines and boosters, especially for residents over 50. 

“Because immunity from the COVID-19 vaccine wanes over time, boosters help to give you added protection against the virus and its strains, both in terms of reducing infections and severe outcomes,” county Public Health Officer Wilma Wooten said in the news release. “People over age 50 are more susceptible to severe illness and complications from COVID-19. If you are eligible, you should get the recommended boosters as soon as possible to protect yourself and those around you.”

Click here to view the county’s COVID-19 daily highlights in a new tab.

Despite the fluctuating COVID-19 cases, there are stark differences for those vaccinated and not. 

The county’s most recent COVID-19 report showed a case rate and death rate for people not fully vaccinated that are two times higher than those fully vaccinated. Last week’s report showed a death rate three times higher. 

The hospitalization rate for residents not fully vaccinated is 1.6 times higher than residents who are fully vaccinated and boosted.

San Diego County spokeswoman Sarah Sweeney said the county defines COVID-19 hospitalizations as patients who either tested positive at the hospital and received care or were already there for some other reason but tested positive upon patient screening.

The county determines this data by looking at average daily cases per 100,000 people who are 12 years and older. People not fully vaccinated had a case rate of 75.59 while people fully vaccinated and boosted had a case rate of 42.13. For people vaccinated without a booster, the case rate was 25.06. 

Shane Crotty from the La Jolla Institute for Immunology told Voice of San Diego during the omicron surge in December that the booster dose of Pfizer or Moderna has “impressive neutralizing antibodies” against omicron. Two doses or less doesn’t quite cut it. 

“The antibodies are mutating,” Crotty said. “It’s a learning process. It’s basically, you go take a class twice and you learn some things. You go to the third class, and you learn some more things. It literally is your immune system learning each time it recognizes it.”

Catherine Allen

Catherine Allen is an intern at Voice of San Diego.

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  1. That was among the most informative, easy to understand piece I’ve seen on the reinfection issue in a while.

    And you are just an intern?

  2. The recovery rate for the HogWash virus in America is 99% whether you take the vaccine or not.
    Worldwide 1 million of the 6 million who have died from the HogWash virus are Americans.
    Americans who are 5% of the world population are reporting 12% of the deaths.
    The media fails to report that this is a biological weapon that was released in China that targets the American population.

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