* More than 30 zones across the city locked down

* Four rounds of mass COVID testing slated this week

* Macau's casinos have been effectively shut for several weeks (Adds details)

By Farah Master

HONG KONG, July 11 (Reuters) - Macau shut all its casinos for the first time in more than two years on Monday as authorities struggle to contain the worst coronavirus outbreak yet in the world's biggest gambling hub.

The city's 30-plus casinos, along with other non-essential businesses will shut for one week and people were ordered to stay at home. Police will monitor flows of people outside and stringent punishments will be imposed for those who disobey, the government said.

Hospitals, pharmacies, supermarkets and fresh food markets are some of the essential services that can remain open.

Macau has recorded around 1,500 COVID-19 infections since mid-June. Around 19,000 people are in mandatory quarantine, according to government figures.

More than 30 zones in the city that have been deemed high risk are now under lockdown, meaning no one is allowed to enter or exit for at least 5 days. While the government said it was not imposing a citywide lockdown, the stringent measures mean Macau is effectively closed.

Macau adheres to China's "zero-COVID" policy that aims to stamp out all outbreaks, running counter to a global trend of trying to co-exist with the virus.

Casinos were last shut in Macau in February 2020 for 15 days.

The government had previously been hesitant to close casinos due to its mandate to protect jobs. The industry employs most of the population directly and indirectly and accounts for more than 80% of government revenues.

Casinos owned by Sands China, Wynn Macau , SJM Holdings, Galaxy Entertainment , Melco Resorts, MGM Resorts, have been effectively shut for the past few weeks, with no gamblers and minimal staffing as per government requirements for people to work from home.

Analysts said it was likely that the suspension could be extended by another few weeks with a recovery in gaming revenue unlikely until the end of the third or fourth quarter.

"Even if the outbreak in Macau gets under control, it will likely be another few weeks before Macau-Zhuhai can remove quarantine requirements," said Terry Ng, analyst at Daiwa Capital Markets in Hong Kong.

Frustration is mounting amongst at the government's handling of the outbreak. Some residents have got into fights at testing centres while others have had to queue for more than 20 hours to access healthcare facilities.

Residents will be required to take part in mass COVID-19 tests four times this week as the government attempts to cut transmission chains.