The Supreme Court on Tuesday declined to immediately halt enforcement of a coronavirus vaccine mandate for health-care workers in Maine.

In a brief order, and without explanation, Justice Stephen G. Breyer rejected a plea to stop the mandate from being enforced at the end of the month. The high court has rejected similar requests to block vaccine requirements for Indiana University staff and students and New York City teachers.

Health-care workers in Maine asked the Supreme Court to intervene last week after a Boston-based appeals court issued a one-sentence order leaving the mandate in place while the legal challenge continues.

The requirement is unconstitutional, the health-care workers say, because it does not include exemptions based on religious objections. Maine officials must “provide protections to employees who have sincerely held religious objections to the Covid-19 vaccines,” according to the emergency petition.

Breyer, who handles such requests from that part of the country, said the workers could renew their request to the high court after the U.S. Court of Appeals for the 1st Circuit issues a decision on the merits of the case or if it does not rule before the state begins enforcing the requirement on Oct. 29.

Breyer did not refer the issue to the full court or ask for a response from state officials in Maine.

In the Indiana case, Justice Amy Coney Barrett, without explanation, similarly rejected the petition from a group of university students.

In New York City, public school teachers are required to show proof of vaccination or to obtain a religious or medical exemption. Justice Sonia Sotomayor denied an attempt earlier this month to block the mandate. She, too, did so without comment.