Sectors across the economy are feeling the pinch amid the circuit breaker period. But supermarkets are bucking the downturn - by feeding the trend of households where families may now have little choice but to cook at home.

Demand has gone through the roof, with customers buying more, while extra staff have been hired to help with the rush and to restock shelves.

While most retail categories registered a double-digit decline in sales in March, when the coronavirus outbreak began to affect consumer sentiment, supermarkets and hypermarkets recorded a 35.9 per cent rise in sales compared with the same month last year.

Supermarket chain Sheng Siong reported a 49.9 per cent jump in net profit to $29 million for the three months to March 31.

The firm says staff, excluding directors, will be rewarded with an additional month of salary for working hard during such a busy period.

A Sheng Siong spokesman told The Sunday Times last week that staff have put in longer hours to meet the surge in demand and "have gone beyond their call of duty and worked very hard".

FairPrice has hired 3,500 temporary and casual workers this month, with more recruiting underway.

Its chief executive Seah Kian Peng declined to disclose exact figures but says the company has seen a "significant increase in sales" due to far more customers visiting the physical and online stores.

He added that the average shopper's basket size has also increased significantly in the last three months compared with the same period last year.

Shoppers are making a beeline for rice and oil, instant noodles and paper products as well as fresh and frozen foods, dairy, condiments and snacks. Flour has also been flying off the shelves as more try their hand at baking at home.

Mr Seah adds that all FairPrice staff will receive a special package in appreciation of their efforts, but no details were given.

Sales have also shot up at Dairy Farm Group, which operates Cold Storage, Giant, Market Place and Jasons Deli.

Mr Chris Bush, chief executive of South-east Asia Food, says the recent months have been the "busiest-ever sales for a sustained period of time" across all the group's supermarkets.

He adds: "Sales across all our brands and formats have seen a change in customer shopping patterns - with frequency of customer visits declining due to the stay-at-home advice but the spending per trip increasing substantially."

The firm has worked with various hotels, including Fairmont Singapore and Mandarin Oriental, to take on more than 100 staff to work temporarily at the supermarkets as cashiers, sales and retail assistants.

They remain employees of the hotels and continue to be on their payroll, while Dairy Farm pays the hotels the salaries it would normally pay staff in those positions.

Supermarket staff have certainly noticed the increase in workload.

Mr Denesh Kumar, 38, director of operations at Cold Storage Singapore, said work has changed tremendously in the past few months.

Though staff do not have to put in longer hours because there is more manpower, he said that the workload during each shift has increased since shelves have to be restocked more often and cleaning frequency at each outlet has increased.

Cold Storage outlets used to have stock arriving every day between Mondays and Saturdays but deliveries are now made on Sundays and public holidays as well.

Mr Kumar says: "Besides staples like fresh produce and rice, lots of people are also stocking up on wine and we've seen a big spike in baking goods. Everyone is trying to bake bread and cakes at home."

He notes: "We usually get so busy only during the festive periods but every day is busy now.

"To me, the staff are real superstars. We all support one another and look out for one another."

Mr Khew Kah Chai, 64, a stacker who has worked at Sheng Siong for more than 22 years, says work has doubled in the last few months: "Even during the Sars period it was not so busy.

"But I am happy to work. I'm not worried about the virus since the company has given us gloves and masks and we make sure to keep a safe distance from customers and other staff."

Correction note: An earlier version of this story wrongly identified Dairy Farm as FairPrice. We are sorry for the error.