Robert F. Kennedy Jr., the health secretary, isn’t just a vaccine skeptic. He especially dislikes one type of vaccine: those that use mRNA technology, such as the first Covid shots. He has canceled nearly $500 million to make mRNA immunizations and a bird-flu vaccine that Moderna was developing.
This is a relatively new technology, and it’s worth remembering the moment the shots debuted for widespread use in late 2020. Three hundred thousand Americans had died from Covid. (The number eventually exceeded a million, the most of any country.) Most schools were still closed. White-collar workers were still mostly remote. Americans were in a mental health crisis. When I got my jab, I hadn’t eaten in a restaurant for a year. The vaccines ended all that.
Kennedy says they’re no good, and he’s halting government support for them. For today’s newsletter, I asked Apoorva Mandavilli, who covers vaccines for The Times, to explain what’s happening.
What is an mRNA vaccine?
Some vaccines use a weakened version of a bacterium or virus to provoke an immune response and train your body’s defenses. Others use a piece of the virus that the body can easily recognize as foreign. MRNA has the instructions for making only one small part of a virus. It directs the body’s cells to make that fragment, which then sets off an immune response.
What is Kennedy’s argument about mRNA?
Kennedy echoes many people’s discomfort with the speed at which the vaccines were developed. But mRNA vaccines had been studied for more than 20 years before Covid struck. His criticisms also go further than most. He has said the vaccines are ineffective because they don’t prevent infection. He has also said they’re dangerous, at one point referring to them as the “deadliest” vaccines ever made.
And what does the evidence show?
Like all vaccines, the Covid mRNA shots have some side effects. Anecdotally, thousands of people reported problems. But extensive studies in the U.S. and elsewhere found only a few serious ones. For example, the vaccines can cause heart problems in a small fraction of young men, and one study said there were seven severe cases of shingles for every million shots administered. This is comparable to the safety record of most other vaccines. It’s not surprising that we’ve heard more about Covid vaccines, because they were given to billions of people worldwide.