New scientific studies continue to offer fresh evidence that coronavirus vaccines are the instrument that will allow the world to move past the pandemic. Still, many doubts linger about how to make them more effective. Many countries have started to roll out a third booster shot, while others are mixing different vaccines in the hope of enhancing the immunity conferred to people.
However, the slow pace of vaccinations in certain countries has created the conditions for a surge in new variants — against which the efficacy of current immunizers remains uncertain.
Trying to get ahead of future demands, Brazilian...
