It is 10.30pm on a Tuesday night and the bar tables at Bangkok's Sugar Club are filling up. As the deejay turns up the volume, two women in bikinis and face shields stride on stage. Strangers flirt.

Step onto the street outside in Sukhumvit Soi 11, and the party fizzles out. Empty bars blast music into the thoroughfare that teemed with tourists before the pandemic.

Two months after Thailand allowed bars and clubs to reopen, Bangkok's nightlife is slowly coming back from the dead.

But the party capital is now grappling with bisecting fortunes.

Businesses that rely on a Thai clientele are seeing crowds return.

Those geared to tourists are desolate, or have simply closed down.

Before Thursday, when Thailand logged a case of community infection, the country had gone for 100 days without any local transmission. There are so far more than 3,400 cases of infection and 58 deaths from the coronavirus.

Wary of a second wave of infections like in Myanmar and Vietnam, the Thai government has shut its doors to most tourists.

It is still hoping to retain a slice of the long-stay market by experimenting with more relaxed quarantine requirements on Phuket.

But the economic prognosis is grim. The Thai economy is set to shrink by 8.5 per cent this year.

One can hardly tell, judging by the revellers on a Monday night in Bangkok's Thonglor district.

Ainu, a bar with live music, was packed with locals.

"We are getting 100 per cent of our customers back, or maybe even more than before," said its manager Sasitorn Thanawat.

Just before the nightspots were allowed to reopen in July, the Centre for Covid-19 Situation Administration had proposed a long list of rules that required establishments to not just maintain distancing but also shut at midnight and stop guests from singing and dancing.

But operators have quietly ignored some curbs.

"After the first three weeks, everybody was trying to get back to normal," said Mr Sanga Ruangwattanakul, president of the Khaosan Road Business Association.

"We cannot operate entertainment establishments with this kind of practice." Still, bars and clubs make staff wear masks and face shields, clean their hands with alcohol, take their guests' temperatures and limit capacities.

Panthera Group, which runs Sugar Club as well as Insanity - one of the largest clubs in Bangkok - has changed its business model.

"With Sugar, a well-established brand in the Thai market, for the most part we just opened the doors and people were there," said Panthera's marketing director Benjamin Baskins.

But Insanity was badly affected as half of its patrons were from other countries like China, Singapore and Malaysia. To attract more Thai clubbers, Panthera tweaked Insanity's music selection and lowered prices by 30 to 50 per cent.

"We are after break-even," said Mr Baskins. "We have settled on the fact that we are really not going to be in the profit zone."

Sing Sing Theater, an upscale club which reopened in late July but chose to operate four days a week instead of six, is running at full or nearly full capacity every night.

"We have not completely recovered," said its general manager Jonathan Siksik.