O'FALLON, Mo. -- Missouri teachers and other school workers are now eligible for COVID-19 vaccines, even as the leader of the state's largest jurisdiction said Missouri's "fumbled vaccine rollout" continues to frustrate urban residents.

Phase 1B, Tier 3, of Missouri's vaccination plan went into effect Monday, adding educators and school staff along with transportation and infrastructure workers to those eligible for shots. The state has estimated the new group includes about 550,000 people.

Democratic St. Louis County Executive Sam Page stressed the importance of vaccinating teachers so schools can return to full in-person learning. But he noted the St. Louis region is still a long way from vaccinating those in earlier groups, and he declined to estimate how long it will be before doses can go to all teachers who want them in the county of 1 million residents.

Leaders in Kansas City and St. Louis have complained that while some rural counties are getting more vaccine than they need, the urban areas are getting so little it has become common practice for people to drive hundreds of miles for shots.

"The fumbled vaccine rollout has added frustration to a process," Page said during a news conference. "Conversations on vaccine equity should have happened before any distribution plan was executed. And seeing our residents drive several hours to snag an appointment or wait in hopes that there are surplus shots at the end of a vaccination event is no way to provide a service critical to ending a pandemic."

Kelli Jones, spokeswoman for Gov. Mike Parson, said conversations about the distribution plan occurred for several months before the rollout. She said the plan finalized in October "has been executed exactly as planned."

Jones said as of last week, 35% of the state's total vaccine allocation has been shipped to the St. Louis region, which makes up 37% of the Missouri's population.

Data on the state health department's COVID-19 dashboard indicates 19.1% of Missouri residents have received at least one shot. The state data shows vaccination rates of 17.3% in Kansas City, 17.4% in Jackson County, 18.1% in St. Louis County and 12.5% in St. Louis city. Leaders in those regions have said the numbers would be worse if people weren't driving to rural vaccination sites.

St. Louis city began vaccinating hundreds of teachers Monday. Page said the county is working with school administrators and expects to announce a plan within a week.

"In-person learning is the ideal setting and our children need to be in a place where they can socialize, develop interpersonal skills and share life experiences with their friends," Page said.

Missouri has reported 483,748 confirmed cases of the coronavirus and 8,310 deaths since the pandemic began. One man who narrowly escaped death was iconic St. Louis Cardinals player and broadcaster Mike Shannon.

Shannon, 81, told the St. Louis Post-Dispatch he spent 15 days in a hospital in October and November with COVID-19.

"I was going down," he said. "I was probably going to die."

After several medicines were tried unsuccessfully at St. Luke's Hospital in St. Louis County, Shannon said doctors turned to the same antibody drug given to President Donald Trump after he contracted the virus and "that turned the trick."

Shannon still is receiving physical therapy three times a week and is working just six innings a game during spring training. But he said his battle with the virus won't deter him from his 50th season in the broadcast booth.

"Just another challenge, you know," said Shannon, whose playing career ended and life was threatened in 1970 by nephritis, a kidney ailment. "It is what it is. But if you're going to step on your bottom lip ... you're just wasting time."