2nds San Diego Breakthrough Death

Another San Diego County resident has succumbed to COVID-19 in a second so-called local "breakthough" case.

In so-called coronavirus breakthrough infections, fully vaccinated people get the illness anyway, despite the fact that the vaccines typically offer strong protection against severe disease. There are rare cases, however, that result in hospitalizations and, rarer still, deaths.

On June 9, a county spokesman said an "older" San Diego woman who was fully vaccinated and had "many pre-existing medical issues" and was sickened by the coronavirus and later died.

At that time, Michael Workman, the county's director of communications, said that of the 1,677,291 San Diegans who at that point were fully vaccinated, there were 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.

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NBC 7's Omari Fleming details the deadly case, and spoke to another "breakthrough" COVID-19 patient.

On Wednesday, Workman sent updated figures to NBC 7, confirming the death of a second victim who was full vaccinated. He also said the county was now aware of 908 breakthrough cases. Seven fully vaccinated San Deigans who were sickened by the coronavirus have required hospitalization.

“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."

As more Americans get fully vaccinated against the coronavirus, the number of breakthrough infections is expected to rise, too. Here’s what you need to know about this medical phenomenon.

According to an Associated Press report, nearly all COVID-19 deaths in the U.S. now are in people who weren’t vaccinated. Its analysis of available government data from May shows that “breakthrough” infections in fully vaccinated people accounted for fewer than 1,200 of more than 107,000 COVID-19 hospitalizations. That’s about 1.1%.

And only about 150 of the more than 18,000 COVID-19 deaths in May were in fully vaccinated people. That translates to about 0.8%, or five deaths per day on average.

The pandemic has been blamed for the deaths of 3,780 people in San Diego since Feb. 14, 2020. As of June 28, San Diego County Health and Human Services Agency (HHSA) officials have reported 282,498 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.

Do San Diegans need to return to wearing masks now with increased concerns of COVID-19’s Delta variant? NBC 7’s Audra Stafford has more on the back and forth.

"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.

The Associated Press contributed to this report -- Ed.