S&P Global Ratings affirmed its'AAA'long-term rating on the Loudoun County Economic Development Authority , Virginia's (the authority) series 2022 revenue bonds and series 2019A fixed-rate capital appreciation revenue bonds, issued for Howard Hughes Medical Institute (HHMI), Maryland. In addition, S&P Global Ratings affirmed its'AAA/A-1+'issuer credit rating (ICR) on HHMI. S&P Global Ratings also affirmed its'AAA/A-1+'dual rating on various series of bonds, issued by the authority and Maryland Economic Development Corp., on behalf of HHMI. The outlook is stable. HHMI's general obligation full faith and credit secures the bonds. The ICR reflects our view of the obligor's general creditworthiness, focusing on its capacity and willingness to meet financial commitments as they come due. The ICR