Hong Kong (CNN Business) Hong Kong stocks recorded their worst day in more than five months after renewed concerns about how the city is handling ongoing protests, and as a new virus spreads throughout China.

Hang Seng Index HSI The city's benchmarkended down 2.8% as it received a double dose of bad news. First, Moody's downgraded the city's credit rating to Aa3 from Aa2, citing an "absence of effective response and lack of clarity" on how the government plans to address political and economic concerns. The city has been gripped by pro-democracy protests for months.

Second, China confirmed that the Wuhan coronavirus — a disease that has killed at least four people and sickened more than 200 in the country — can be transmitted between humans

There have been no confirmed cases of the virus in Hong Kong. But there have been 14 cases in neighboring Guangdong province, including one in nearby Shenzhen.

Shares of Hang Seng components were down across the board. Major property developers like Wharf Real Estate Investment Company and Hang Lung Properties were among the worst performers, having lost more than 4%. Chinese car maker Geely Auto was the worst performer — down 5.3%.

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