Moderna Inc said on Thursday its Covid-19 vaccine was about 93% effective through six months after the second dose, showing hardly any change from the 94% efficacy reported in its original clinical trial.<br /><br />However, the company said it still expects booster shots to be necessary ahead of the winter season as antibody levels are expected to wane.<br /><br />It and Pfizer Inc and partner BioNTech SE, which make a similar messenger RNA-based vaccine, have been advocating for a third shot to maintain a high level of protection against Covid-19, especially as more contagious variants of the virus spread widely.<br /><br />-Reuters -
