* Delta coronavirus variant is a risk factor for stocks and economy
* Surging Delta cases delay if not reverse plans to bring workers back to offices
* Scientists say plan for Covid-19 vaccine booster shots next month is premature
* China OKs sweeping privacy law that will curb data collection by tech firims
* US Philly Fed Mfg Index indicates slower growth in August
* US Leading Economic Index reports ‘another large gain in July’
* US jobless claims fell to a new pandemic low last week: