A new phrase has been creeping into our coronavirus vocabulary lately: “breakthrough case.” That’s when someone who’s been fully vaccinated against the virus becomes infected.
On Tuesday, the Centers for Disease Control and Prevention recommended that vaccinated people in areas with high or significant levels of transmission should go back to wearing a mask in public indoor spaces. By the CDC’s definition, that would include all of the Charlotte area.
How worried do you need to be if you’ve already gotten your vaccine as the highly contagious delta variant spreads rapidly?
WFAE’s health reporter, Claire Donnelly, spoke with "Morning Edition" host Marshall Terry.
Marshall Terry: Claire, how many breakthrough cases have there been in North Carolina?
Claire Donnelly: There have been roughly 4,660 breakthrough cases, according to preliminary state numbers. But that's only through July 11 — so more than two weeks ago. The state says that of those cases, 321 people were hospitalized and 61 died.
Terry: How does that compare to the total number of people in the state who have been vaccinated?
Donnelly: It’s a minuscule percentage. The state has vaccinated some 4.9 million people. Those breakthroughs are only about one-tenth of a percent of that.
Terry: Those are the state numbers. But how do they break down at the county level?
Donnelly: We don’t know specific numbers for Charlotte or Mecklenburg County yet, and it seems like the county doesn’t know either. County health officials say they need to get those numbers from the state ... which is a work in progress.
Terry: Why does the county need to get its breakthrough numbers from the state?
Donnelly: We don’t know and county officials didn’t say. But what we do know is that to find these cases, the state health department is linking up its vaccine database with its disease reporting system. Basically, they’re comparing their statewide list of vaccinated people with their statewide list of who’s tested positive for COVID-19.
Also, in Mecklenburg County, health department workers are still doing contact tracing. Remember, that’s after someone tests positive for the virus and workers try to notify everyone that they came into contact with. Now that process also includes asking people whether they’ve been vaccinated, according to county medical director Dr. Meg Sullivan.
Terry: How worried should fully vaccinated people be?
Donnelly: Sullivan says it can’t hurt to take a few extra precautions because there is more virus circulating than there was before, and the delta variant is highly contagious.
Sullivan (recording): I think the reason, though, that we all have to have a level of precaution is to understand — and we’ve said this from the beginning — the vaccine is not 100% effective at preventing someone from testing positive or necessarily preventing someone from spreading it. It absolutely is highly effective. It significantly reduces your chances of either one of those. So a fully vaccinated individual, we’re still asking, right, to take some level of precaution.
Donnelly: Even if you’re vaccinated, Sullivan says you should get tested if you have COVID-19 symptoms. And just Tuesday, the Centers for Disease Control and Prevention said that fully vaccinated people in some places should go back to wearing masks in public, indoor spaces. And we know that masks prevent the spread of the virus.
According to Sullivan, you should be most worried if you’re not vaccinated. Unvaccinated people make up the vast majority — around 94% — of new cases in North Carolina and 99% of people hospitalized with COVID-19.
