People 80 years and older can start getting a COVID-19 vaccine this week as Ohio opens up to Phase 1B.The process can only move so fast as the supply still slowly trickles in.Some in Phase 1A still have not completed their doses.Officials said there are challenges ahead.Last week, Hamilton County launched a website to give people information about how to get on the list for a shot, but the struggle starts with supplies."I think that's where we are living right now, trying to do our best work with the limited doses that we're getting," Hamilton County Commissioner Denise Driehaus said.As Ohio's Phase 1B starts with people 80 and older, Driehaus said there are 28,000 people over the age of 80 in the county and there are about 8,000 doses of vaccine coming for distribution.It quickly shows there's a lot of demand but little supply."You've got 1A, right, still getting their doses. Then, you add in the 80-year-old and older. A week later, we add in 75 and older. So, the 80-year-olds are still on the list, they haven't all gotten vaccinated and now we're adding another group and then a week after that, we've got 70 and older added to the group. It's like, wait a minute," Driehaus said.At Hamilton County Public Health, work is underway to schedule people 80 and older for vaccinations this week."Our agency is anticipating 500 doses of Pfizer vaccine," Hamilton County Health Commissioner Greg Kesterman said.That's a small number of doses compared to the interest Kesterman sees building by the day.He said more than 37,000 people of all ages have registered online wanting a vaccine."It's really important to realize that availability of vaccine right now is limited," Kesterman said.The goal is getting shots in arms quickly, as officials navigate a slow pipeline of product."I think the confusion's going to be, 'Oh man, where am I on the list?' and so, it's just, it's going to get complicated here," Driehaus said.The big hurdle right now is figuring out when even more doses are coming.There's also hope that more vaccines will get the Food and Drug Administration's Emergency Use Authorization soon to help with the slow, trickling supply.Seniors can learn more about the vaccine by calling the United Way's 211 number in Hamilton County.The county has also launched this website with more information about who is eligible for the COVID-19 vaccines and where people can sign up.