The deadly coronavirus has been the impetus for these new codes.

ICD-10-CM has significantly changed in that we are now getting updates, albeit limited ones, twice a year. The bulk of changes and additions are made on Oct. 1, but on April 1 of next year, we are getting a few as well. COVID-19 has been the impetus for this evolution of adaptation, and the upcoming codes relate to the virus: (

There is not a good way to monitor breakthrough infections currently, unless one were to read the medical record in its entirety. We were instructed (and I concurred) to not use Z28.3, Underimmunization status in the context of COVID-19. If the vaccines are being administered under an emergency use authorization (EUA) and there is no general mandate, then how can you conclude that someone is underimmunized? The intent of that code was to identify infants and children who have not undergone the recommended vaccination regimen.

It is no April Fool’s joke that on April 1, 2022, this code set is expanding. The upcoming codes are:

  • 310, Unvaccinated for COVID-19;
  • 311, Partially vaccinated for COVID-19; and
  • 39, Other underimmunization status.

“Unvaccinated” is obvious. Defining “partially vaccinated” is going to be problematic. A person is considered fully immunized two weeks following the second dose of Pfizer or Moderna, or two weeks after a single-dose vaccine, e.g., Janssen/Johnson & Johnson (J&J). But we have determined that immunity wanes.

As of Friday, Nov. 19, the Centers for Disease Control and Prevention (CDC) expanded eligibility for booster shots to all adults. They are recommending booster shots for all J&J recipients at least two months post-initial dose, essentially rendering it a two-dose series. For Pfizer and Moderna, the recommendation is that a third full-dose shot be given to patients who are immunocompromised. For others, a booster shot is now suggested. Moderna’s booster shot is a half-dose, whereas Pfizer’s is administered in the same dosage as the first two shots. The CDC is also now allowing for mixing and matching manufacturers.

Some states had already taken the extraordinary step of expanding eligibility for COVID-19 boosters for everyone 18 and older, exceeding the recommendations of the Food and Drug Administration (FDA) or CDC; Arkansas, California, Colorado, New Mexico, and West Virginia had done so.

What is ultimately going to constitute “fully vaccinated?” Two weeks after a second dose of Pfizer or Moderna, and within six months after completing the primary series, a person is fully vaccinated. But after the six months have elapsed, am I now considered only partially vaccinated? What happens if we discover we need a yearly booster shot? Those vaccination cards are really not going to fit into our wallets!

It seems to offend some folks’ sensibilities that a code was created for this single virus vaccination. COVID-19 has infected over 250 million people worldwide and caused over 5 million deaths, with more than 750,000 deaths in the United States alone. It is the only airborne pandemic of this magnitude that we have lived through. Coronaviruses do not mutate at the speed with which influenza morphs. It is very important to capture data on who is coming down with breakthrough infections.

We are so fortunate that scientists were able to develop such safe and efficacious Coronavirus vaccines in such an expeditious fashion. Overall, there are 14 immunizations or series recommended for all adults over the age of 18: (

My sister was a guinea pig for the chicken pox vaccine, and I don’t remember any societal resistance in 1995, when varicella vaccine was added as a mandatory vaccine by each state and Washington, D.C. for children in school or daycare, unless they had permanent natural immunity from having had the disease. No one pitched a hissy fit when a safe rotavirus vaccine was added to the childhood vaccination schedule in 2006 (, either. The CDC has not been able to add COVID-19 to its list yet because of the political climate, and who knows if it ever will.

We are going to have to see what the official guidance is regarding the concept of partial vaccination. All I know is that Z28.311 is a code that will never grace my medical record. If they told me I need a booster every six months, I’d do it. I consider myself lucky to have side effects heralding the development of antibodies and protection.

Please have a safe and happy Thanksgiving! It is still not advisable to have huge gatherings, especially if people are unvaccinated. The prevalence is trending up again, especially in cold climates. If you can request that your guests be vaccinated and eat outside, open some windows, or use an air filter, you will be safer. If everyone gets vaccinated, maybe next year the holidays can go back to the old normal.

Programming Note: Listen to Dr. Erica Remer live today when she co-hosts Talk Ten Tuesdays with Chuck Buck at 10 Eastern.

Share This Article