"Second Dose of Pfizer Vaccine After 4 Weeks?" [Correspondent Diary]

Principle Changed to 3 Weeks After First Dose for Pharmacy Convenience
Criticism Arises After Media Coverage Leads to Reversion to 3-Week Rule

A pharmacist at a CVS pharmacy is preparing for vaccination. In American pharmacies, pharmacists administer vaccines. (Photo by Baek Jong-min)

[Asia Economy New York=Correspondent Baek Jong-min] The United States is aggressively rolling out COVID-19 vaccinations. With over 200 million doses administered, both the reporter and family members were able to receive the vaccine. It has been about four months since vaccinations began.

Although vaccinations are rapidly increasing, with nearly 10,000 new COVID-19 cases daily in New York and New Jersey (population approximately 29 million), vaccination remains essential.

All three family members were vaccinated at different locations. They were at Walgreens (a major U.S. pharmacy chain included in the Dow Jones Industrial Average as Walgreens Boots Alliance) and CVS.

At the vaccination sites, only ID verification against the reservation list was required before receiving the vaccine.

However, there was something puzzling. Unlike other places, Walgreens did not specify the vaccine type at the time of reservation. Because the automatically set interval for the second dose was 4 weeks, it was naturally assumed that the Moderna vaccine was being administered.

The reporter's vaccine appointment status indicates that the Pfizer vaccine will be administered at 4-week intervals.

The vaccination certificate received afterward had a sticker with the serial number of the Pfizer vaccine.

The U.S. Centers for Disease Control and Prevention (CDC) recommends a 3-week interval for Pfizer vaccinations. Other major pharmacy chains like CVS and Rite Aid not only specify the vaccine type but also follow the CDC’s recommended dosing intervals.

Because of this, the reporter’s daughter, who received the Pfizer vaccine at CVS a week later, had her second dose scheduled on the same day as the reporter’s second dose.

Vaccinees who were confused about the dosing interval inquired with Walgreens, but the only response was that the CDC’s position is that the second dose can be administered within 6 weeks after the first dose.

Those uneasy about the dosing interval found it practically impossible to change their appointments to the 3-week interval. Due to difficulty in making reservations, changing appointments was out of the question.

Walgreens’ 'trick' was revealed through reporting by The New York Times (NYT). Walgreens explained to NYT, "Administering the second dose at a 4-week interval is faster and more convenient for the pharmacy than doing it at 3 weeks, so we chose to do it that way."

Handling both Moderna, which has a 4-week interval, and Pfizer, which has a 3-week interval, Walgreens unified the dosing schedule to 4 weeks for the convenience of the pharmacy.

With growing concerns about vaccine side effects such as blood clots from Johnson & Johnson and AstraZeneca vaccines, vaccine recipients are naturally sensitive to even small changes. For those eager to complete vaccination as soon as possible, a one-week difference is significant. A one-week delay could potentially reduce vaccine effectiveness and increase the risk of infection.

NYT criticized Walgreens for prioritizing their convenience over the health of vaccine recipients in choosing the dosing interval. Amid growing controversy, Walgreens has now decided to administer Pfizer vaccines at the 3-week interval going forward.

However, NYT also reminded readers that some argue extending the dosing interval is necessary to expand early vaccine coverage. Since the first dose provides substantial protection, delaying the second dose to increase the number of people receiving the first dose may be a better vaccination strategy, according to some experts.

In fact, Canada is focusing on expanding first-dose coverage by extending the interval for the second dose up to 4 months.