(TNS) — As people frantically stock up to prepare for possible coronavirus home quarantines, some are outsourcing their panic buying, using delivery services like Postmates or Instacart for groceries, Amazon for a wide variety of goods and DoorDash or Uber Eats for restaurant meals.

Whether delivery companies can keep up is another question.

Amazon notified customers of its Prime Now delivery service on Monday that it's taking longer than normal to deliver orders, with the app sometimes displaying a message that no delivery windows were available. The scarcity of couriers also affected Amazon Fresh, according to Bloomberg News, which attributed the delays to a surge in demand.

"It's like it's Christmas all over again," said Nestor Vela, a full-time Amazon delivery driver in California's East Bay who works for ONCI Logistics, an Amazon contractor. "Our loads are a lot heavier and there's been a bunch of big orders."

Amazon did not immediately reply to a request for comment.

Instacart, the grocery delivery service headquartered in San Francisco, has also seen a wave of orders, against a backdrop of store shelves emptied by people preparing for a possible pandemic.

"Over the last few days, we've seen a surge in customer demand for household essentials such as bottled water, as well as personal care products like hand sanitizer," the company said, adding that it remained "fully operational across North America and aimed for uninterrupted service.

Relying on others for shopping may be a positive, said Karan Girotra, a professor of operations and technology at Cornell Tech in New York.

"Going into a large public place like a grocery store is less desirable," because of the risk of contagion, he said. "Delivery services can serve an important role by decreasing how much people get together in big stores."

Of course, the delivery workers themselves may be at risk if they're bringing goods to the homes of sick people. For the gig workers responding to app orders, who generally are independent contractors, there's another wrinkle: They only get paid if they work, which means they have to balance making money versus the possibility of exposure.

"Most of the prepper orders I did, the customer didn't tip well, they don't want to go to the store (because) they might get sick, but they think nothing of the person who is shopping in that store for them," said Krystal Asche, an East Bay Instacart shopper and delivery driver, in an email. "I have been coughed on and sneezed on so many times these past few days."

She's also concerned about hand sanitizer and disinfectant wipes being sold out and wishes stores would limit quantities to prevent hoarding.

"I need that stuff to do my job, so I don't pass anything onto somebody with a compromised immune system," Asche said. "I have enough hand sanitizer for a few more days, after that I don't know what I will do. Driving around shopping and delivering, I don't have access to a sink to wash my hands all the time."

For the gig companies, there's a delicate balance: They may be limited in what they can tell workers because exerting control is among the factors that could result in workers being reclassified as employees under AB5, California's new gig-work law. No on-demand companies responded to questions about whether they are concerned about this, or whether they're noticing reluctance among workers even while demand surges.

DoorDash, Uber, Instacart, Postmates, UPS and FedEx all said they are informing their drivers and couriers about public-health officials' recommended hygiene precautions, such as frequent hand washings and staying home if sick.

"The safety and health of our community of employees, merchants and Dashers is always our top priority," DoorDash said. "We are closely monitoring this situation and have shared the CDC guidelines with Dashers and merchants. We will remain in close contact with them as we learn more."

Uber likewise said safety is a top priority. "We have formed a dedicated global team of Uber operations, security and safety executives, guided by the advice of a consulting public health expert, to respond as needed in each market where we operate around the world," it said.

UPS noted that, according to the World Health Organization, packages are not at risk of contamination. "From previous analysis, we know coronaviruses do not survive long on objects, such as letters or packages," the company said.

San Rafael cannabis delivery company Moonflower Delivery said it is keeping antibacterial wipes and hand sanitizer in vehicles for drivers to use after deliveries, since payment involves using a touchscreen.

"We also have drivers disinfect the phone screens since customers have to sign the digital receipt," co-owner Alexa Wall wrote in an email.

In China, where millions are under home quarantine, delivery people have become essential. While most households can only send someone out for supplies every three days, scooter-driving couriers are still allowed on the streets.

The couriers have become a lifeline for food and necessities -- but also are particularly vulnerable to infection. The government has ordered them to hang packages on doorknobs or leave them outside gates, rather than handing them over in person, according to the Wall Street Journal.

Bay Area public health officials didn't respond to questions about whether they were developing extra protocols for delivery drivers here.

"A lot of the delivery folks will become frontline individuals supplying things to people and protecting them from the spread of the virus, as we saw in China," said Girotra, the Cornell Tech professor. Companies "should expect more business and should protect their (workers), providing personal protective equipment as much as they can. These are high-risk jobs."

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