WHYY By COVID vaccine in syringes ready for inoculations. (Nelvin C. Cepeda/The San Diego Union-Tribune via AP, Pool) Delaware now has open second-dose slots at its mass vaccination event at Dover International Speedway for people who received their first shot elsewhere before Jan. 22. Previously, the ongoing event where about 3,000 people are getting the critical second inoculation dose a day had only been open to residents whose first shot came at these four Division of Public Health events: Dover Division of Motor Vehicles, Jan. 16-18. Salesianum School in Wilmington, Jan. 18. Delaware City Division of Motor Vehicles, Jan. 22-24. Georgetown Division of Motor Vehicles, Jan. 23-24.