It was an exercise in frustration last week as an editorial writer tried to track down when guidance is coming for those who received Pfizer or Moderna COVID-19 shots months ago and are still waiting for the green light for a booster.

Answers are needed soon from federal health authorities. Minnesota and other states are in the midst of another COVID surge, a troubling place to be as winter weather drives us inside and holidays loom, creating conditions ideal for viral spread.

Emerging scientific findings add to the urgency. A large new study, one published earlier this month in the prestigious journal Science, found alarming drops in protection against infection over the past year for all three vaccines authorized for use in the United States. Thankfully, the vaccines' ability to prevent fatal cases of COVID proved more durable, but researchers also found that this protection varied depending on age and the type of vaccine.

While health officials have cleared many vaccine recipients for an additional shot, there's been a frustrating lack of communication for Pfizer and Moderna recipients who are not yet eligible. The dearth of information is unacceptable and requires remedy.

Boosters have been OK'd for all Johnson & Johnson adult recipients two months after immunization. Adults who got Pfizer or Moderna are also eligible six months after their initial vaccine series if they are 65 and older, reside in long-term care, have underlying medical conditions, or live or work in high-risk settings.

That still leaves out a lot of Pfizer and Moderna recipients. Many who got their shots last spring are now past the six-month mark, the time period when the Science study found vaccine protection waned against infection. They're understandably wondering when it's their turn for boosters.

Unfortunately, federal health authorities continue to neglect this large group of vaccine recipients. An editorial writer's questions last week to the U.S. Centers for Disease Control (CDC) and the Food and Drug Administration (FDA) disturbingly yielded little guidance.

The CDC failed to respond to three separate inquiries about when booster guidance for this group can be expected. The FDA replied, but shed little light. "We are working to accrue additional data as quickly as possible to further assess the benefits and risks of booster doses in lower age groups and plan to update the health care community and public with our determination in the coming weeks,'' a spokeswoman said.

On Tuesday, Canada expanded booster eligibility, authorizing a Pfizer booster for adults over 18. Israel was an early adapter, expanding eligibility in late August to all over 12. Data from Israel's COVID public health dashboard suggests boosters restore high levels of protection against infection and severe disease across age groups.

This week, Pfizer submitted a request to the FDA to authorize a booster for all who are 18 and older. California and Colorado also opened up booster eligibility to all adults this week.

There has been considerable debate among American health officials about authorizing an additional shot for the general population. One objection is that resources are better used to vaccinate the unvaccinated. Or, that vaccines are more urgently needed globally. In a paper published in September, two FDA officials also argued that more evidence was needed to justify broad use of boosters.

Data has accumulated since then. It's unclear why the FDA and CDC are taking so long to make a decision, but it feels as if U.S. is falling behind on vaccine guidance instead being on the leading edge. FDA and CDC scientists and physicians are among the world's top experts. They are faced with momentous, complicated decisions. But that's no excuse for leaving worried vaccine recipients waiting for answers.