The US Centers for Disease Control and Prevention released new guidance on Wednesday offering "best practices" for managing second doses of Covid-19 vaccine and making sure people get their second shots so that they are fully vaccinated.
The Pfizer/BioNTech and Moderna Covid-19 vaccines authorized for emergency use in the United States are administered as two doses, 21 and 28 days apart, respectively.
"If it is not feasible to adhere to the recommended interval, the second dose may be scheduled for administration up to 6 weeks (42 days) after the first dose," according to the new guidance posted to the CDC's website.
The guidance notes that "jurisdictions and providers must carefully manage vaccine inventory to ensure completion of the vaccine series. At present, jurisdictions receive sufficient supply of doses to vaccinate all persons who receive a first dose."
Local health officials were told on Tuesday during a phone call with the White House that the guidance provided recommendations around what to do if patients miss their second-dose appointments, Lori Tremmel Freeman, chief executive officer of the National Association of County and City Health Officials, told CNN on Wednesday.
"This guidance that is coming out is intended to share how health departments -- and others who are distributing the vaccine -- can deal with people who miss their second appointments and how long they should save that vaccine for that patient," Freeman said.
"This guidance is meant to provide some protocols that health departments can use so that they can address missed appointments."