Former Secretary of State Colin Powell died of complications related to Covid-19 despite being fully vaccinated—leading health experts to stress the importance of mass vaccination to reduce community spread and protect the vulnerable.

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Elderly and immunocompromised

When Powell died, he was 84 years old and fighting multiple myeloma, a cancer that attacks the body's plasma cells, which build antibodies that provide essential immune protection, the New York Times reports.

Multiple myeloma can also attack a person's bone marrow, preventing healthy plasma cells from developing. The disease is rare and accounts for just 1.8% of all cancers in the United States, according to the National Cancer Institute.

Powell had been fully vaccinated with the Pfizer-BioNTech vaccine and planned on getting a booster shot but fell ill before his appointment, according to a spokesperson.

Because of his cancer, Powell was in an especially vulnerable group: He was both elderly and immunocompromised. "He had two strikes against him already," said Celine Gounder, an infectious disease specialist. "He was just not going to respond as well to the vaccines."

Recent CDC data has shown that, among vaccinated individuals, the risk of dying from Covid-19 is highest among those ages 80 and older—although the death rate in this group is still lower than that in unvaccinated people ages 50 to 64, the Washington Post reports.

One factor is that the immune system in elderly individuals may mount a sluggish response to vaccination. A recent study, which has yet to be peer reviewed, found that among residents of long-term care facilities in Canada—whose median age was 88—neutralizing antibody levels after vaccination were about five- to six-fold lower than staff members, whose median age was 47.

"This puts them at risk for not only getting infected by Covid but also having severe consequences," said Anne-Claude Gingras, lead author of the study and a senior investigator at Lunenfeld-Tanenbaum Research Institute at Mount Sinai Hospital in Toronto.

In addition, a recent study published in Nature found that, among the participants with multiple myeloma, less than half produced "an adequate response" to the Pfizer-BioNTech and Moderna Covid-19 vaccines.

"That's to be expected if somebody is immunocompromised—their immune systems will not respond as well," Gounder said.

James Berenson, medical and scientific director of the Institute for Myeloma and Bone Cancer Research, explained that treatments for the disease "are indiscriminately knocking off both the malignant and the normal immune cells."

As a result, patients are "at double risk for getting no response to a vaccination and also not responding as well once they get the disease," Berenson said.

Even multiple myeloma patients in remission can have weakened immune systems, Berenson added.

"They usually—not in all cases, but usually—maintain an immune-suppressed state even if they've had a good response to their treatment," he said. "Their antibody levels in most cases don't go back up to normal."

Why vaccinating the community is so important

According to the Post, some vaccine skeptics are using Powell's death as a reason to cast doubt the effectiveness of Covid-19 vaccines. But public health officials say Powell's death actually shows why it's so important for everyone to get vaccinated, as high community vaccination rates can help protect immunocompromised individuals from being exposed to the coronavirus in the first place.

"Breakthrough deaths with vaccinated individuals do occur," said Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine. "But there are certain groups that are at greater risk."

According to an analysis of data from 40 states by the Times, breakthrough infections have accounted for between 0.2% and 6% of all Covid-19 deaths.

The best way for vulnerable groups to be protected is for everyone else to get vaccinated, according to Ashish Jha, dean of the Brown University School of Public Health.

"When there are large numbers of infections happening in the community, it spills over into vaccinated people," he said. "And the vulnerable are really at risk." (Nisen, Bloomberg/Washington Post, 10/18; Kolata, New York Times, 10/18; Linskey, Washington Post, 10/19; Anthes, New York Times, 10/18)