A new study suggests that the effectiveness of the Pfizer-BioNTech COVID-19 vaccine may decrease over time, particularly in older adults. The research found that vaccine protection against infection dropped from 88% to 47% in people aged 75 and older after four months. This highlights the importance of booster shots to maintain immunity, especially for vulnerable populations. The findings underscore the need for ongoing monitoring of vaccine efficacy and the potential need for additional doses to combat the virus.
