Cashier Joanne Sim has seen plenty in her two decades working at a supermarket, but the sight of shoppers panic-buying last weekend was a first for her.

"Every cashier counter had long queues, and I was very surprised as I have never seen this happen before," she said.

"But I also understand that the customers were taking precautions to protect their loved ones."

Shoppers rushed to stock up on essential items such as rice, instant noodles and toilet paper after the alert level rose to orange on Feb 7.

Supermarket shelves across the country were cleared out that weekend with long queues at checkouts.

Ms Sim, who is a cashier at Eccellente by Hao Mart at Kinex Shopping Mall, said: "Looking at the queues, I didn't want any customers to go home empty-handed.

"I was willing to work longer so that all customers could check out but, thankfully, we were still able to close by our usual time of 11pm."

The anxiety did not seem to have affected Ms Sim, 58, who was the face of calm when asked about working as a front-line staff amid the virus outbreak.

"Life goes on, right? It has to," she said with a shrug.

Her husband, she noted, is potentially in an even more vulnerable position as he works as a customer service agent at Changi Airport.

"Things happen, but we still have to go about our daily lives and go to work. As long as we maintain good hygiene and keep calm, I think it'll be fine."

All the cashiers have face masks, she added, which she dons whenever she serves customers. She also takes pains to wash her hands more regularly throughout the day and she wipes down the checkout counters whenever possible.

Ms Sim takes vitamin C tablets every day to boost her immunity.

"So I'm really not worried about falling sick. The only thing I'm worried about is when the outbreak will be over so that I can go on holidays again. I love to travel," she said.