"When you are treating a person with an underlying health condition like cancer or some autoimmune diseases you are actually affecting their immune system. So, the medications that people are taking or even the disease itself may actually make your immune response not as good as a healthier individual," said Dr. Yvonne Maldonado, Stanford Prof. Global Health and Infectious Disease.
Dr. Yvonne Maldonado, Stanford University's Professor of Global Health and Infectious Diseases believes Powell's breakthrough case is a prime example that even when vaccinated there is always a risk of infection. Especially if you are 65 years old or older or have underlying health conditions.
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"No vaccine is 100% and I think people are expecting a miracle. This is a miracle the fact that we can prevent 5 to 20% of infection with the vaccine, it's a miracle and you know people want one simple answer. Yes, I got my vaccine and I can go out and take my mask off and never worry again. That is just never going to happen," said Dr. Maldonado and added, "We also know that after four to six months there is evidence that the immunity overall drops."
We met with UCSF's Dr. Timothy Henrich, he's been leading a study on breakthrough cases to understand what's causing severe disease. He believes some patients could benefit from multiple booster shots.
"Patient or have blood cancers or other conditions that suppress the immune system that sometimes a third and even potentially a fourth dose is needed in order to develop the same antibody and same immune response that those without immune compromise conditions achieve," said Henrich.
The latest CDC data shows a total of 7,178 breakthrough cases of COVID-19 have resulted in death. Of those breakthrough cases 85% were among people age 65 and older and 57% were among men.
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"We know for example that there might be biological differences between males and females that prevent males from fighting that very initial infection during the first few days or week or so. There may also be higher amounts of risk factors, hypertension, obesity, diabetes for example in older males. Also, males may be approaching the medical system later in the national history of disease," said Henrich.
One of Powell's longtime spokespeople confirmed to ABC7 News that Powell was scheduled to receive a booster shot.
Breakthrough cases are extremely rare. More than 187 million people in the U.S are fully vaccinated and there have been 31,000 breakthrough cases. That's a 0.017% of a chance.
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According to a Nature study that focused on people with multiple myeloma only 45% of them developed an "adequate" immune response after receiving either the Pfizer or Moderna vaccines. The study also pointed out that 22% had a "partial" response.
That's why Dr. Hernich believes those who are immune compromised could benefit from boosters shots.
Dr. Maldonado doesn't believe booster shots are necessary for everyone, "We don't think there is very strong evidence that the vaccines are wearing off for everybody but people over 65," said Dr. Maldonado.
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