SAN FRANCISCO (CBS SF) – SFMTA officials began rolling out cuts in several “short” lines Monday in anticipation of upcoming staffing shortages due to the COVID-19 vaccine mandate for city employees.

The agency said service is being suspended on some lines including the 1 California Short, 14R Mission Rapid Short (weekends only), 30 Stockton Short and 49 Van Ness Short (weekdays only).

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“We made the difficult decision to cut the supplemental short line service because it may be temporarily eliminated without jeopardizing access to any stops or connections along the full route,” officials said in a statement last week.

SFMTA officials said customers may experience additional crowding and longer wait times.

“The bus was taking a little longer than usual,” Michael Looking said Monday afternoon while waiting for a Muni bus. “Usually that early in the morning, it’s not a problem.”

The transit agency had warned riders about “noticeable service disruptions” starting in November, noting that 275 of the agency’s 6,000 employees had yet to be vaccinated or disclosed their vaccination status as of October 18.

However, by last week, that number had dropped considerably.

“We’ve been able to educate our membership about what’s going on citywide, state wide, nationwide pertaining to the COVID-19 vaccines,” said Roger Marenco of Transport Workers Union Local 250-A told KPIX 5 on Thursday. “And we’ve been able to reduce our numbers drastically. I think it’s less than 100 at the moment.”

The agency reported that 110 transit operators did not work on Monday because they were either not fully vaccinated or had not reported their vaccine status. That figure also includes those requesting an exemption for the vaccine requirement. Some of those workers will receive paid leave as their request is processed, according to Mareno.

“It has an extremely negative trickle down in the sense that if one operator is not here for whatever reason, then that’s one bus or one train,” he said.

While some riders shared the buses seem more crowded that usual on recent trips, the agency says they’re not concerned about the potential increase in virus infections on their buses or trains.

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“Muni is one of the safest places you can be in terms of avoiding and spreading the virus,” said Jeffrey Tumlin, the executive director of SFMTA. “Crowding on transit does not seem to be a significant source of COVID spread.”

Infectious disease experts say riders still need to be cautious even though they live in a city with a high vaccination rate and this mandate ensures the workers they come into contact with on Muni will meet safety requirements.

“Chances are you’re in good company with people who are protected against COVID,” said Dr. Annette Regan with the University of San Francisco’s School of Nursing and Health Professions. “Public transportation is one of those places where we know as much as we try, unfortunately, we’re not always able to maintain that six-foot distance and this is why I wouldn’t back down on mask wearing.”

On Monday afternoon, the agency tweeted that riders on a number of bus lines — the 22, 24, 29, 43 and 45 — could see delays “due to multiple coaches not being in service on each route.”

The agency also said staffing shortages due to the mandate could affect parking enforcement.

SFMTA said it does not have a precise timeline on when service would be restored, but said they are continuing to work with operators to address their vaccination status and that new operators are being hired and trained. Tumlin said he hoped the service would improve by the end of the week because of this particular staffing issue.

The city’s vaccination policy requires all employees to be fully vaccinated by November 1, 10 weeks after the Food and Drug Administration gave full approval to at least one of the authorized vaccines.

Dr. Regan encouraged riders to see if they can be flexible in their schedule and wait for a later or bus or try to catch an earlier trip to avoid crowded buses. A suggestion some have already started practicing.

“The buses have been crowded, especially getting back from Downtown, Financial District,” said Zorah Baptista. “Oh yeah, I’ve waited a few times to take a few different buses just because I’m not going to go ahead and risk it and get on a crowded bus, even when I’m wearing two masks.”

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Shawn Chitnis contributed to this report.