As the highly infectious BA.5 variant spreads across the US, experts say they're wearing masks outdoors, especially in crowded settings, to protect against contracting COVID-19. The BA.5 Omicron subvariant appears to better escape the disease-fighting antibodies produced after vaccination or prior infection than other subvariants, which means people are more likely to become infected, irrespective of prior immunity — though vaccines will still stop most from getting sick