Despite getting vaccinated against COVID-19, Colin Powell remained vulnerable to the virus because of his advanced age and history of cancer, highlighting the continued risk to many Americans until more of the population is immunized.

Powell, 84, had been treated over the past few years for multiple myeloma, a blood cancer that impairs the body’s ability to fight infections -- and to respond well to vaccines.

“The more people that are vaccinated, the less we have viral spreading in the community, the less chances of people like him getting infected to begin with,” said Dr.

Moreover, people with weakened immune systems because of illnesses like cancer -- or cancer treatments -- don’t always get the same level of protection from vaccinations as healthier people.

Several studies have found as few as 45% of people with multiple myeloma may develop protective levels of coronavirus-fighting antibodies after getting the vaccine.