Four months after receiving the J&J vaccine, I want to know if it makes sense to get the Pfizer or Moderna vaccine as a booster shot. Unfortunately, living in the United States does not make it easy.
There are several issues that I am considering.
First: The Delta Variant
Some good news is that 49% of the U.S. population is fully vaccinated, with 57% partially vaccinated. My state of Massachusetts is 62% fully vaccinated. These numbers are slowly rising.
The bad news is COVID-19 cases are skyrocketing. Over the span of a month, the U.S. quintupled the number of daily positive cases – from 10,000 in June to 50,000 in July. The CDC says the Delta variant is responsible for 83% of new cases. Other variants such as Lambda are also making news, albeit on a smaller level.
Second: The J&J Vaccine
Johnson & Johnson announced data at the beginning of July that indicated immune response lasts for eight months, and that its vaccine protects people from the Delta variant.
While published in a scientific journal, the study used a small sample of 20 participants. Critics argue that more people are needed.
A subsequent independent study from New York University concluded that the J&J vaccine may reach less than 50% protection against variants.
The New York Times interviewed scientists on both sides of the issue and explained why nobody is in agreement.
CNN published a well-written profile of doctors who recommend supplementing the J&J vaccine with a mRNA vaccine. Other doctors in the piece suggest that until federal agencies authorize or approve booster shots, the status quo should be maintained.
Third: Mixing Vaccines
While U.S. agencies research the reliability and safety of mixing COVID-19 vaccines, this practice is already in place around the world. German Chancellor Angela Merkel made waves last month when she received a Moderna dose two months after getting an AstraZeneca one.
J&J and AstraZeneca built vaccines with a similar architecture that use a modified adenovirus. After injection, the body creates a spike protein and then develops antibodies. Pfizer and Moderna vaccines use mRNA.
Canada Prime Minister Justin Trudeau and Italy Premier Mario Draghi also received mixed vaccines of both AZ and either Moderna or Pfizer.
Italy, Germany, Spain, South Korea, and Thailand are among many countries that allow residents to get second doses of other vaccines.
The New York Times wrote on July 20 that the AZ vaccine has 33% protection against the Delta variant. (This is aligned with the above-mentioned NYU study about the J&J vaccine having less than 50% protection.)
Fourth: Breakthrough Cases
Breakthrough cases are defined as people who test positive after being fully vaccinated.
Here in Massachusetts, the latest weekly data indicated breakthrough cases represented 43% of new positive cases. In other words, nearly half of new COVID-19 cases are from people who are fully vaccinated.
The numbers may be low in contrast to the total vaccinated population, but looking at data from earlier this month, 303 breakthrough cases were hospitalized and 79 died.
While it’s true that about 99% of Delta cases are among the unvaccinated, does this mean that I should wait for breakthrough case numbers to increase before pursuing additional vaccination?
The National Institute of Allergy and Infectious Diseases (which Dr. Anthony Fauci directs) is recruiting J&J vaccine recipients for a clinical trial to investigate long-term effects of mixed vaccines.
The kicker is that the estimated study completion date is in May 2025.
If that’s my benchmark, that’s a long time to wait for the U.S. government to decide if 13 million U.S. residents who received the J&J vaccine should be able to get another vaccine.
In the meantime, I asked my primary care physician for his thoughts if I should get a booster. He implied that the government may recommend it in the future and added, “Until then, it’s up to you.”