person to ever hold office, but fit for duty according to walter reed. one note of observation was an increase in the president's throat clearing and coughing. the doctors say that's the result of acid reflux in the throat. and they looked at the president's walking abnormality and it's due to normal wear and tear and no specific treatment is needed. this is biden's first exam since taking office in january. there was a brief moment of history for 85-year-old -- 85 minutes, kamala harris was madam president. the cdc gave its final stamp of approval for pfizer and moderna hours after the fda gave them the green light. >> nbc's anne thompson tells us