When it comes to the one-two punch delivered by two doses of COVID-19 vaccines, this is the second shot that really falters.
Kristen Choi can testify to that. Choi, a nursing researcher at UCLA, had a bunch of symptoms, including fever that reached 104.9 degrees after she got her second shot last year. But the consequences passed quickly – and it was worth the much-needed protection against the pandemic, she said.
“I am very grateful that I got the vaccine and was able to get the protection, and really want to see the opportunity made available to everyone,” Choi said.
As more Americans opt for the COVID-19 vaccine, some are anxious about the two-dose side effects, which tend to be stronger than the first. But experts believe the symptoms, ranging from a sore arm to headaches and nausea, are a sign that the second dose is doing its job: the immune system responds to the initial dose of turbocharging and thus delivers more vigorous and longer lasting protection against the virus.
Two of the three vaccines allowed in the US – one made by Pfizer and BioNTech, the other by Moderna – require two doses, three and four weeks apart respectively. (Johnson & Johnson’s vaccine is a one-time agreement.)
There is no special secret sauce in the second dose: both the first and second shots are exactly the same. The first makes the immune system primer so that it is ready to start a more robust response when it is time to roll up a sleeve again.
“It’s basically a reinforcement of the same process that is happening for the first time,” said Dr. Diane Griffin, an expert in infectious diseases at the Johns Hopkins Bloomberg School of Public Health, said.
Common side effects include pain, redness and swelling on the arm that gets the shot, according to the Centers for Disease Control and Prevention. Typical side effects elsewhere in the body include fatigue, headaches, muscle aches, chills, fever and nausea.
And if you do not experience any side effects, it is ‘absolutely fine’, said Dr. Grace Lee, an expert on infectious diseases at Stanford Children’s Health, said. Your body is still doing its job.
“The good thing is, not everyone gets a response,” Lee said.
The Pfizer and Moderna vaccines work by giving the body cells a blueprint to make a replica of the vein protein of the virus. Before an immune cell responds to the offending replica by destroying it, the defender develops a memory of the protein so that it can attack again in the future.
“The fever, headache, etc., that you experience are due to the inflammatory proteins that do their job in the body to get rid of what he thinks is an outsider,” said Dr. Jasmine Marcelin, an expert in infectious diseases. at the University of Nebraska Medical Center, explained in an email.
Choi experienced it first hand. She volunteered for a clinical trial to test the Pfizer BioNTech vaccine and got her first chance in August. There were virtually no side effects – just a sore arm.
But after Choi’s second dose, her arm quickly became much more painful at the injection site. At the end of the day, she suffered from chills, nausea and headaches. Around midnight she wakes up with an arm that is so sore that she can barely lift it. At 5:30 a.m., she developed a terrifying high fever.
She takes Tylenol and drinks water. Her fever turned about 99.5 degrees for the rest of the day. The next morning, her symptoms disappeared (except for a sore, swollen bump at the injection site).
Choi described her experiences in an essay published in JAMA Internal Medicine in December. Since then, she has said she has received emails from hundreds of people, many of whom have said they have come across her account, saying it is reassuring to know that these reactions are common, and OK. (Choi learned after publication that she had indeed received the vaccine and not a placebo.)
To make it clear, it is rare to have such intense symptoms as those experienced by Choi: only 4 out of a subset of 8183 participants in the larger clinical study experienced fever above 104 degrees (and two of them were in the placebo group) , according to data published in the New England Journal of Medicine and posted on the CDC website.
Besides arm pain, fatigue and headaches were the most common side effects after the second dose.
Although there are some cases of severe allergic reactions with both the Pfizer-BioNTech and Moderna vaccines, it is extremely rare. Just to be safe, the CDC recommends that people be monitored for 15 to 30 minutes after receiving their shot so that they can receive immediate treatment if necessary. Someone who experiences symptoms such as swelling in the throat, itching, hives or breathing problems after leaving the vaccination site should seek medical attention immediately, experts said.
Those who have an “immediate allergic reaction” to a first dose of the Moderna vaccine or the Pfizer-BioNTech vaccine should not receive a second dose, the CDC says. But for all the others, the experts agree: Get the second chance.
Compared to suffering from a real attack with COVID-19 – not to mention the possibility of fighting long-term complications of the disease, there is actually no fight, said Lee, the expert on infectious diseases for children. .
“Vaccines are a much safer way to develop immunity,” she said.
And if you have never been infected with this coronavirus, you need the second dose of vaccine to ensure that your immune system is strong and that it will last over time, experts said.
Choi noted that people aged 55 and younger suffer more from side effects than the older crowd. There is a reason for this, she said: “When you are younger, your body has a stronger immune system and a little more ability to boost the immune response.”
So as more vaccine becomes available and younger people act for their shots, it is important to let them know what to expect, and that side effects are a normal part of the process.
“It’s a sign that the vaccine is working,” she said.