By Tuesday, their number skyrocketed by 90 percent from four days earlier when they had not received the kits, ride-hailing firm Gojek told VnExpress. It has managed thousands of orders in the last few days as a result, it said.

Since September 25, Gojek has been distributing the free test kits provided by the government at 36 locations. It requires one third of its drivers pick up the kit between 6 a.m. and 4 p.m. every day since the frequency of testing is once every three days.

They self-test on the spot under the supervision of specialized staff. "On average, there are 10-15 drivers every hour at a test point," Gojek said.

Food delivery startup Baemin also said more drivers returned to work after it began distributing the free test kits.

A company spokesperson said: "The number of drivers has increased by about 35 percent compared to September 24. Many drivers like this policy and are excited to go out on the road".

Another food and grocery delivery service said in the past four days thousands of its shippers had done the quick tests at home. It also allows drivers to get tested at medical facilities, and grants them VND500,000 ($21.88) for testing if they complete 60 deliveries between September 24 and 30.

The company with the largest number of delivery workers in Ho Chi Minh City, Grab, has also seen a large number of drivers come to receive the free kits.

Grab said there has been no congestion or large gatherings at the kit distribution spots.