Many are unable to service their debts to banks or pay suppliers, and have lost customers, according to a report by the Vietnam Association of Seafood Exporters and Producers (VASEP).
The remaining 30 percent also face operational challenges as costs surge and they can only mobilize 30-50 percent of their workforce.
Average production has fallen by 40-50 percent, and companies also face difficulties in buying packaging and other materials.
VASEP has proposed that workers in the industry should be prioritized for vaccination, which would help workers keep their jobs and factories to remain open.
It also proposed that factories should be allowed to test their workers twice a month and send the samples to health authorities to reduce the burden on government medical personnel who are already overworked.
It wants workers in the industry to be eligible for loans at lower interest rates and a 30-percent reduction in electricity tariffs until the end of this year.