OAKLAND (CBS SF) — COVID infections among frontline workers at the Alameda-Contra Costa Transit District will result in delays on bus routes beginning Friday, the district said.

AC Transit said a spike in positive cases has been reported throughout employee ranks since the New Year’s holiday. COVID-related sick calls among bus drivers, mechanics and other employees are now resulting in “a discernable impact” on service.

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COVID protocols on testing, along with isolating employees who test positive, have symptoms, and who have been in close contact with anyone COVID-positive have caused staffing shortages that will effectively mean a route scheduled for 15-minute frequency may now mean a 30-minute wait for riders.

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AC Transit said that in isolated instances, the district could be forced to temporarily cancel a bus line.

“Nevertheless, in keeping with our pandemic policies, we will equitably prioritize bus lines, including those to under-resourced, transit-dependent, and high-demand communities,” the district said in a press statement.

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Before planning their next commute, riders were asked to realtime bus arrivals at actransit.org/actransit-realtime.