On the same day that local health officials announced that San Diego County would be shifting on Wednesday to the state's least restrictive, yellow tier, they also said a San Diegan who was fully vaccinated had died from COVID-19-associated illness in a "breakthough" case.
In so-called coronavirus breakthrough infections, fully vaccinated people get the illness anyway, but the vaccines typically offer strong protection against severe disease. There are rare cases, however, that result in hospitalizations and, rarer still, deaths.
Michael Workman, the county's director of communications, said the person who died was an "older" woman who had "many pre-existing medical issues" and "had been sick and then hospitalized before succumbing."
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Workman said that of the 1,677,291 San Diegans who are now fully vaccinated, there have been 458 breakthrough cases, representing 0.4% of all county COVID-19 cases this year. Of those 458 infections, four people have been hospitalized with the illness, and there was one fatality.
“We expect to see those numbers," the county’s deputy public health officer, Dr. Eric McDonald, said in April in reference to the county's first breakthrough cases. "They are very, very low and emphasize how good the vaccines work."
The pandemic has been blamed for the deaths of 3,764 people since Feb. 14, 2020. San Diego County Health and Human Services Agency (HHSA) officials have reported 280,807 positive COVID-19 cases since the beginning of the pandemic.
Approximately 25% of people who test positive as a breakthrough case are asymptomatic, according to a report issued in late May by the Centers for Disease Control and Prevention. The report also showed that most of the breakthrough infections are contracted by women.
"The report cautions, however, that these cases are likely an underestimate because most people who have been fully vaccinated aren't being regularly tested," NBC News reported in May.
The CDC, in an effort to focus on severe breakthrough cases, is no longer regularly reporting mild breakthrough cases, NBC News also reported.