(Reuters) - Federal courts in some parts of the United States are imposing new vaccine and masking requirements or reducing in-person court proceedings and trials in January in response to a rising number of COVID-19 infections and the fast-spreading Omicron variant. For the most part, federal courts from California to New York are avoiding shutting their doors entirely as they did at the start of the pandemic in early 2020, when states imposed business lockdowns and stay-at-home orders pre-vaccines. But some are taking extra measures to protect their staff, lawyers and jurors in the face of the Omicron variant, which the World Health Organization says is causing infections in people already vaccinated or who have recovered from COVID-19. Chief U.S. District Judge James Bredar in Maryland in a Wednesday order called the Omicron variant "an impediment to recovery" as he announced new restrictions and the postponement of jury selection until Jan. 25. He said that while his court had already re-implemented virtual hearings for some cases, those steps were "insufficient to fully mitigate the risks posed by the present circumstances." In Manhattan, the Southern District of New York starting Monday will require anyone in its courthouses to wear N95 or KN95 masks "in light of the numbers in New York City," said Edward Friedland, the district court executive, said Thursday. U.S. District Judge Alison Nathan alluded to the requirement on Wednesday when she told jurors in British socialite Ghislaine Maxwell"s sex abuse trial that when they returned on Monday, the court would provide them such masks. "Please stay safe over the long weekend," Nathan told them. Friedland said the court currently plans to still conduct trials in January given other previously adopted safety protocols, such as increasing the size of jury boxes and having witnesses testify from plexiglass booths. But some trials in other courts are being bumped. In the Eastern District of New York, on Wednesday, a Jan. 10 trial in Central Islip of an alleged MS-13 gang associate was delayed to March 14. In Boston, U.S. District Judge William Young on Wednesday delayed a Jan. 18 trial of a man accused of stealing trade secrets from a technology company to March 1 "in the light of the emergent public health situation." At the appellate level, the San Francisco-based 9th U.S. Circuit Court of Appeals in a Tuesday order said staff and attorneys appearing in-person will have to get their booster to meet a previously imposed vaccination requirement. The patent-heavy U.S. Court of Appeals for the Federal Circuit in Washington, D.C., on Wednesday revised its safety protocols and mandated that everyone regardless of vaccination status present a negative COVID-19 test to attend hearings. Read more: "Stay safe," judge says, as Maxwell jury breaks for Christmas amid COVID surge