Recent data from the Epic Health Research Network has found that breakthrough Covid-19 infections, while uncommon, are significantly more likely to affect elderly and immunocompromised individuals.
The demographics of breakthrough infections
The Wall Street Journal analyzed data from Epic Health, which includes records for 19.5 million people who have been fully vaccinated against Covid-19.
The Journal found that, so far, about 1.2% of fully vaccinated people have experienced a breakthrough infection.
The data also showed that people ages 65 and older were significantly more likely to be hospitalized with a breakthrough infection than younger people. Also, about 80% of deaths from breakthrough infections occurred among those 65 and older.
Separately, the Journal reviewed aggregated state data and found that among more than 21 million fully vaccinated people, there have been over 1.89 million breakthrough cases; 72,000 hospitalizations; and 20,000 deaths this year.
The Journal found that people with diabetes, chronic lung disease, kidney disease, and compromised immune systems were the most at risk of severe outcomes from breakthrough cases.
'The Never Again Plan': Moderna CEO Stéphane Bancel wants to stop the next Covid-19—before it happens
For example, data from South Carolina showed that 79% of people hospitalized with a breakthrough infection had at least one underlying health condition, as did 88% of those in the ICU with a breakthrough infection.
According to Andrew Goodwin, section chief of critical care at the Medical University of South Carolina (MUSC), almost all of the fully vaccinated Covid-19 patients in MUSC's ICU have weakened immune systems from other health conditions.
2021 Covid-19 deaths surpass 2020's toll
Meanwhile, the number of Covid-19 deaths in the United States in 2021 surpassed the death toll of 2020, according to federal data and data from Johns Hopkins University. The Journal notes, however, that deaths may have been undercounted in 2020, when the disease was new and testing was scarce.
As of November 20, the total number of Covid-19 deaths in 2021 in the United States hit 770,800 according to Hopkins' data, more than twice the 385,343 deaths reported in 2020, according to CDC data.
Epidemiologists argue that low vaccination rates and fatigue with Covid-19 precautionary measures such as masking led the highly contagious delta variant to rapidly spread in 2021, especially among unvaccinated individuals, the Journal reports.
"Heading into this year, we knew what we needed to do, but it was a failure of getting it done," said Abraar Karan, an infectious diseases doctor at Stanford University.
CDC data shows that Vermont, the most vaccinated state, with 72% of its population vaccinated, has had the lowest Covid-19 death rate per 100,000 people since the start of the pandemic. Mississippi, which has a 47% vaccination rate, has had the highest.
Covid-19 deaths occur primarily among older people, CDC data shows, but younger people are representing a growing number of deaths as they disproportionately remain unvaccinated, the Journal reports. Last year, 81% of Covid-19 deaths occurred among those ages 65 and up, compared to 69% so far this year.
Covid-19 deaths among younger people are rarer. However, 20,563 people under the age of 45 have died from Covid-19 so far this year, more than double the number of deaths in that age group from Covid-19 last year.
"There are plenty of what we call the young invincibles who just didn't get around to getting a vaccine," said Olveen Carrasquillo, chief of the internal medicine division at the University of Miami's Miller School of Medicine, "and a lot of meetings with family where they say, 'Oh, he's so stubborn, we told him to get vaccinated, but he wouldn't.'" (Kamp/Evans, Wall Street Journal, 11/21; Kamp et al., Wall Street Journal, 11/20)