July 19 (Reuters) - Wall Street’s main indexes fell sharply at the open on Monday, with economy-linked value and travel stocks taking a hit after a spike in global COVID-19 cases raised fresh concerns about slowing economic growth. At 09:31 am, the Dow Jones Industrial Average fell 463.52 points, or 1.34%, to 34,224.33, the S&P 500 lost 50.24 points, or 1.16%, to 4,276.92 and the Nasdaq Composite lost 163.29 points, or 1.13%, to 14,263.95. (Reporting by Devik Jain in Bengaluru; Editing by Sriraj Kalluvila)