Gen. Colin Powell died Monday morning from COVID-19 complications, according to his family.

Powell is considered a pioneer, a man who broke down racial barriers both in the military and in government. Powell was the first Black secretary of state, national security advisor and chairman of the Joint Chiefs of Staff.

Powell’s family posted a statement on Facebook saying the 84-year-old was fully vaccinated. “We have lost a remarkable and loving husband, father, grandfather and a great American.”

According to multiple news reports, Powell was being treated for multiple myeloma, a form of blood cancer, at Walter Reed National Medical Center before his death.

He was also reportedly living with Parkinson’s disease, which is a progressive nervous system disorder that affects movement.

Doctors say these factors most likely contributed to Powell's death despite being vaccinated.

“Vaccination is not perfect. Vaccination is very, very effective and very important. What I know about Colin Powell. He was 84. He was male and he had a history of a condition that impacts directly on the immune system. A condition called multiple myeloma. These are all factors that make anybody more vulnerable to the COVID virus, “says Dr. Bruce Hirsch, Northwell Health infectious disease expert.

Diana Berrent had COVID-19 in March 2020 and now runs Survivor Corps, dedicated to helping educate and connect patients and survivors.

She says that some cancers or treatments for cancer impede the production of antibodies.

“So, it is important that everybody be vaccinated because there are so many people, we don’t know are battling things behind the scenes and are not fully vaccinated even though they received all of their dosages,” Berrent says.

Powell’s chief of staff confirmed to news stations that Powell had his second Pfizer vaccine in February.

He was reportedly scheduled to get his booster shot this past week but fell sick and wasn’t able to receive it.