BERLIN, Aug 10 (Reuters) - Investor sentiment in Germany deteriorated for the third month in a row in August on fears that rising COVID-19 infections and a fourth wave of coronavirus cases could hold back the recovery in Europe’s largest economy, a survey showed on Tuesday. The ZEW economic research institute said its survey of investors’ economic sentiment fell to 40.4 from 63.3 points in the previous month. A Reuters poll had forecast a fall to 56.7. “This points to increasing risks for the German economy, such as from a possible fourth COVID-19 wave starting in autumn or a slowdown in growth in China,” ZEW President Achim Wambach said in a statement. A separate ZEW gauge of current conditions rose to 29.3 from 21.9 in July. That compared with a consensus forecast for 30.0 points. “The clear improvement in the assessment of the economic situation, which has been on-going for months, shows that expectations are also weakening due to the higher growth already achieved,” Wambach added. (Reporting by Michael Nienaber Editing by Madeline Chambers) Our Standards: The Thomson Reuters Trust Principles.