BEIJING, Aug 24 (Reuters) - The benefits of China"s zero-tolerance approach to COVID-19 continue to outweigh the costs but it should cut back on excessive measures that risk exhausting people, a former Chinese disease control official said on Tuesday. Zeng Guang, former chief epidemiologist at Chinese Center for Disease Control and Prevention, said "flood-like" measures and policies that prove inefficient should be avoided even though China has the financial resources to keep pursuing the goal of zero local infections. Since late July, China has brought under control clusters of infections driven mainly by the highly transmissible Delta variant of the new coronavirus. That was achieved by swift contact tracing and locking down areas deemed high-risk, even when only a handful of cases were detected. In cities where most infections were found, multiple rounds of testing on local populations were undertaken and travel restrictions imposed. Those measures have required significant human resources and have disrupted the tourism, services and logistics sectors, prompting analysts to downgrade forecasts for China"s economic growth for the quarter ending in September. "It becomes more difficult for us to have zero infections with the Delta variant, and the cost (of achieving that) has increased," Zeng told an online presentation. "But we still have to continue to (aim for) zero infections, because the dividends of doing so still exists." Zeng was part of a top team at China"s National Health Commission when the virus started to spread from the central city of Wuhan to other parts of China last year. Noting that China was the only major economy to grow last year, Zeng said "we have the financial resources" to support the zero-tolerance strategy. "If we want to, we can tap (the equivalent of) one-tenth of our GDP growth to deal with Delta," he added.