The 14-day lockdown in Samut Sakhon to contain a new outbreak will cost manufacturing and logistics in the province 1 billion baht daily and affect 345,284 Thai and migrant workers, Federation of Thai Industries (FTI) estimates.
The government has imposed drastic measures, including a 10pm-5am curfew, following a new surge of more than 500 infections over the weekend, with the Central Shrimp Market believed to be an epicentre for the contagion.
The outbreak is causing grave concerns because, according to FTI chairman Supant Mongkolsuthree, Samut Sakhon is a major production base for food processing, garments and textiles, auto parts and rubber products.
"Samut Sakhon has a total of 6,082 factories, with 233,071 migrant workers and 122,213 local workers," he said.
Some 334 factories, employing 91,395 workers, are FTI members. They are mostly in the food processing industry.
The outbreak in Samut Sakhon erupted amid growing worries over illegal border crossings from Myanmar, which has been suffering from high infection numbers. Border authorities have been tasked with preventing illegal entry of migrant workers from Myanmar.
The government has so far regulated employment of foreign labourers through a memorandum of understanding (MoU) signed with neighbouring countries.
The FTI has called on the government to use MoUs as part of efforts to solve illegal entry of migrant workers. Many of them end up becoming cheap labourers in factories.
"We support the government to make agreements with Myanmar, Cambodia and Laos. The government should set an appropriate quota for workers," said Mr Supant.
A total of 3.2 million foreign workers, mostly from Myanmar, have registered with the government while up to 37.6 million Thai workers are registered with authorities.