Vietnam's benchmark VN index fell 1.6 per cent in midday trading, hitting its lowest level since may 19th. The index is down 10% from its recent closing high on July 2 and is set to enter a technical correction.

"investors are now worried about the spread of COVID-19 's epidemic across the country," said Toshifumi Sugimoto, chairman of Capital Asset Management Co., a capital asset management company.

Commercial Bank of Vietnam (Vietcombank) and Techcombank were the main drag on the index, falling at least 3.1 per cent.

The VN index is up 16% year-to-date.

The Vietnamese stock market hit an all-time high earlier this month. The benchmark index became the world's worst-performing stock index this month after surging 28 per cent in the first six months of the year.