Amazon.com Inc on Thursday said it could post its first quarterly loss in five years because it is spending at least $4 billion in response to the coronavirus pandemic, including plans to test its workforce for Covid-19.

Shares of Amazon, the world’s largest online retailer, fell 5 per cent in after-hours trade.

Jeff Bezos, the company’s founder and the world’s richest person, said in a statement, “We’re not thinking small”, a sign that the e-commerce company would invest heavily during the pandemic. Rival brick-and-mortar retailers have had to shut stores, while Amazon hired 175,000 people.

This quarter, withUS government-mandated lockdowns in full swing, Amazon said it could see a 28 per cent rise in revenue to $81 billion.

Under normal circumstances, Amazon would earn an operating profit of at least $4 billion in the current second quarter, but its costs will rise by that amount or more so it can respond to the pandemic, the company said. The Seattle retailer forecast operating income will range from a loss of $1.5 billion to a profit of $1.5 billion, versus earnings of $3.1 billion in the same period a year prior.

Amazon has unsettled investors in the past with heavy spending on cloud data centers, streaming video and voice-controlled gadgets, which often paid off in the form of new businesses. Since mid-February, Amazon’s shares have risen by more than 10 per cent, including Thursday’s after-hours drop, while the broader stock market has sunk.

Bezos’ personal stake alone has grown by some $5 billion in that time.

The company is increasing investments because of the novel coronavirus in a similar way, said Kim Khan, US markets analyst at Investing.com.

“Amazon built its commanding position by spending all its cash to grow before it became the profit-making machine it is today. It’s doing the same thing during this lockdown period and will likely come out a winner again,” Khan said.

At the same time, Amazon is facing new labour risks. The virus has infected workers at dozens of locations, igniting small protests and prompting labour organisers to demand site closures.

Amazon has rolled out masks and temperature checks to all its US and European warehouses, announced software to monitor for social distancing and taken other measures to ensure it stays operational.