The 41, who are factory workers aged between 19 and 34, pleaded guilty under Rule 6(1) of Prevention and Control of Infectious Diseases (Measures within the Infected Local Areas) Regulations.
The charges were read to them in Burmese by an interpreter.
They committed the offence on April 12 at the Kilang Hartalega hostel here.
Deputy public prosecutor Nurul Faraheen Yahya urged the court to impose a deterrent sentence against the workers.
Their lawyer G Rajasingam however urged the court to impose a minimum sentence, saying they were low-wage earners.
Police had arrested 62 Myanmar nationals for participating in a gathering for the traditional water festival at their hostel.
A 30-minute video clip shared on social media showed a group of foreign workers dancing and singing to celebrate Songkran at a factory.
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