Data from several states and the federal government suggests deaths among Americans fully vaccinated against COVID-19 rose sharply amid the nation’s most recent surge of infections, but experts say that is not unexpected as more of the population gets immunized.
Between Oct. 11 and Oct. 18, the Centers for Disease Control and Prevention’s cumulative count for breakthrough deaths jumped by 51% from 7,178 to 10,857. Some conservatives and vaccine skeptics have pointed to the seemingly drastic increase to bolster arguments against mandatory immunization policies.
“40% of all covid deaths last week were vaccinated. Stop vaccine mandates & forced masking,” Rep. Marjorie Taylor Greene, R-Ga., tweeted in a post Twitter flagged as “misleading.”
However, the CDC stressed the breakthrough data is not collected in real-time and it can take several weeks for a case to be reported, so the change does not represent a sudden week-to-week swell in deaths. The page tracking breakthrough deaths only includes data from 16 state and local health departments, and it is not intended to provide an exact count of U.S. cases at a given time.
"National surveillance relies on passive and voluntary reporting, and data are not complete or representative. These surveillance data are a snapshot and help identify patterns and look for signals among vaccine breakthrough cases," a CDC press officer said.
The death of former Secretary of State Colin Powell last week from COVID-19 complications despite being fully vaccinated cast fresh scrutiny on the risk of breakthrough infections. However, Powell was 84, had Parkinson’s disease, and had been treated for multiple myeloma, a form of blood cancer that can weaken the immune system.
“Colin Powell was probably at as high risk as you could possibly be for a breakthrough infection with COVID,” said Dr. Timothy Murphy, director of the Clinical and Translational Science Institute at the University at Buffalo.
Powell’s death sparked a wave of misinformation and misleading memes on social media as anti-vaccine activists cited the failure of the shots to protect him as proof that they were not as effective as health officials claimed. Experts strenuously disputed that conclusion.
“I hope people don’t take away from this that vaccination is not effective,” Dr. Chris King, a transplant pulmonologist at Inova Fairfax Hospital in Virginia, told WJLA last week. “I think that’s the absolute wrong message. I think the overwhelming thing that’s coming out of the data is that vaccination is effective.”
A CDC analysis conducted in 13 U.S. jurisdictions as the delta variant began to spread between mid-June and mid-July found the fully vaccinated accounted for 16% of deaths, 14% of hospitalizations, and 18% of all new infections. Researchers said the frequency of breakthrough cases was higher than expected and reflected a possible decline in vaccine efficacy, but the vaccines still provided substantial protection against severe outcomes.
That trajectory continued through the summer. In 16 jurisdictions representing 30% of the U.S. population, the death rate among the vaccinated jumped from 0.1 per 100,000 people in late June to 1.2 per 100,000 at the height of the delta surge in August. Among the unvaccinated, though, the death rate per 100,000 people went from 1.9 to 13 during the same period.
According to a CDC report published earlier this month, 85% of breakthrough deaths in the U.S. through August occurred in adults 65 and older. Studies have also shown people with underlying medical conditions are at greater risk for severe breakthrough infections or death.
While research suggests breakthrough deaths and hospitalizations remain relatively rare, it does seem clear that they have become more common. Maryland Gov. Larry Hogan said Monday 30% of recent COVID-19-related deaths in his state – where 86% of adults have received at least one dose of a vaccine – have been among fully vaccinated people with existing medical issues.
“The vaccines are outstanding, but they are not perfect,” said Dr. Martin Blaser, director of the Center for Advanced Biotechnology and Medicine at Rutgers University. “They offer a very high level of protection, but not for all people, especially people who are immunosuppressed, as Gen. Powell was.”
Readily available data on breakthrough cases varies widely by state. Officials are often imprecise about when deaths occurred, warning of lag times of several weeks before cases are included in the total counts, which makes week-to-week comparisons difficult.
“You need to be careful because the way the counting is done can have a big impact on the numbers we see,” Murphy said. “It’s important to look at the trends as opposed to the individual changes that happen over short periods of time.”
In South Carolina, only about 10% of COVID-19 patients whose deaths were reported in June were fully vaccinated, according to the Department of Health and Environmental Control. In August and September, the vaccinated accounted for about 25% of COVID-related deaths.
“We continue to see the majority of severe cases occurring among our fellow South Carolinians who are not fully vaccinated,” Dr. Brannon Traxler, DHEC public health director, said earlier this month. “Not being fully vaccinated puts people at increased risk of being hospitalized or dying if they become infected with COVID-19.”
A report from the Oregon Health Authority last week also showed breakthrough deaths spiked during the delta variant surge, representing 21% of COVID-19 deaths in the state in August and September. Prior to the summer, fewer than 10% of Oregon virus-related deaths involved the fully vaccinated.
“The proportion of vaccine breakthrough cases who have died with COVID-19 has increased over time,” the report stated. “This trend is likely multifactorial and may be associated with increased COVID-19 transmission in our communities, increased disease severity associated with infection caused by the Delta variant, and waning immunity over time in elderly populations.”
In Minnesota, the Department of Health found breakthrough death rates remained steadily below 1 per 100,000 fully vaccinated people from May through mid-September, while the unvaccinated death rate at times topped 10 per 100,000. Amid the delta surge in late summer, deaths among the fully vaccinated 65 and older more than doubled, but they were still about 20 times less likely than among the unvaccinated in the same age group.
“As more people become vaccinated, it is natural to see more cases of vaccine breakthrough (no vaccine is 100% effective),” the department said in its latest weekly update. “However, vaccines remain highly effective at preventing severe disease, hospitalization, and death.”
California similarly experienced a notable rise in hospitalizations and deaths among the vaccinated during the delta surge, but the spike among the unvaccinated was far more dramatic. In recent weeks, the unvaccinated in the state were 10 times more likely to be hospitalized and 15 times more likely to die than those who were fully vaccinated.
The vast majority of the vaccinated continue to be protected from infection. In Washington, D.C., breakthrough cases at times accounted for up to one-third of new infections in August. However, fewer than 2% of fully vaccinated residents have been infected overall.
New Jersey Gov. Phil Murphy reported Wednesday that breakthrough cases represented about 21% of new infections in the state during the week of Oct. 4, but only one of the 124 COVID-19 deaths recorded statewide in that time. Since January, 0.004% of the fully vaccinated in New Jersey have died from the virus.
The latest report from the Ohio Department of Health indicates just over 2% of COVID-19-related deaths and fewer than 5% of hospitalizations since January have been among fully vaccinated individuals. In Maine, though, about 20% of all COVID-19 hospitalizations and deaths since mid-April have been breakthrough cases.
“When you do the math, you find that unvaccinated people are somewhere around 10 times as likely to die if they become infected as unvaccinated people,” Blaser said. “People should understand these numbers, so they can make decisions that will promote their own health.”
Other countries with high vaccination rates have seen similar trends: the vaccinated have accounted for a larger share of raw deaths in recent months, but their death rate is still considerably lower. Data from the United Kingdom indicates most COVID-19-related deaths reported in September were among the vaccinated, but death rates among the unvaccinated were still 2.5 to 9 times higher, depending on the age group.
“When you look at who’s dying, it is people who have underlying illnesses and the elderly,” Dr. Murphy said. “Those are the folks who got the vaccine the earliest and are likely losing a little of their protection.”
The latest guidance from the CDC and the Food and Drug Administration on booster shots underscores concerns that protection from the vaccines could wane over time. The agencies are now recommending boosters for the elderly and high-risk patients who received any of the three vaccines authorized in the U.S., and CNN reported last week they could soon call for anyone over 40 to get an extra shot.
“The evidence shows that all three COVID-19 vaccines authorized in the United States are safe – as demonstrated by the over 400 million vaccine doses already given,” said CDC Director Dr. Rochelle Walensky in a statement. “And, they are all highly effective in reducing the risk of severe disease, hospitalization, and death, even in the midst of the widely circulating delta variant.”
Research from the U.S. and Israel has indicated the protection against COVID-19 transmission provided by the vaccines may fade after several months and an additional dose can help shore up immunity. However, there is still some debate among experts over how urgently boosters are needed and how much they would help.
A preprint study published this week in medRxiv concluded effectiveness of the Pfizer vaccine against infection declines by about 20% after eight months, but a third shot can bolster protection back to 87%. The authors concluded more immunization of unvaccinated people around the world would be the most effective means of containing COVID-19, but a booster dose for the vaccinated offers “sizeable” benefits.
“The only thing that effectively stops the virus in the long-term is immunity,” Blaser said. “The more immunity in a population, the higher the walls against viral spread.”