With fall coming into view, public health officials across the country are turning to the annual task of persuading legions of Americans to get vaccinated against some combination of influenza, Covid-19, and respiratory syncytial virus, three bugs that sicken mass numbers of people over the winter months, often overwhelming hospitals and health care delivery in the process.
The standard advice — get your shots, get them at the same time, don’t wait too long to roll up your sleeves — is designed to maximize convenience and compliance, in a way that is manageable for the delivery enterprise, say experts familiar with the enormous effort it takes to turn vaccines into vaccinations. But is it the right approach for you?
Possibly not, though unfortunately, there is no one-size-fits-all answer here. Because while we talk about cold and flu season, in reality these viruses strike at different times in different years, and they do not give us advance notice of their plans. The immunity we develop from the available vaccines — at least those for Covid and flu — erodes in the months after we get them. If flu season takes off in January, a shot administered in August won’t have the impact of a shot received in late October.
But figuring out how to maximize the benefit of these vaccines by calculating the optimal time to get them is never going to be an exact science.
“If we could have a crystal ball, then we’d be able to time things just right. There’s risk in waiting, and there’s risk in getting it too soon,” said Scott Hensley, a professor of microbiology at the University of Pennsylvania.
STAT spoke with a number of experts to ask their advice on when people should get their shots, and whether it’s best to get two or three at once (depending on whether you qualify for an RSV vaccine), or to space the vaccines out.
The clear consensus was that if you are likely to only have the time, the inclination, or the patience to make and keep one vaccination appointment, by all means, get your flu and Covid shots together — and RSV, if you are eligible for it. (More on RSV later.) The Centers for Disease Control and Prevention says it is acceptable to get all these vaccines in one go.
Veteran influenza researcher Arnold Monto, co-director of the Michigan Center for Respiratory Virus Research and Response and a professor emeritus of epidemiology at the University of Michigan, favors timing the vaccines to when you’ll get the most from each of them individually. But he added: “It’s better to get both together than not to get one or the other.”
If you’re willing and able to make and keep more than one vaccination appointment, there are a variety of factors to take into consideration about when to time the shots, with the current Covid surge being experienced across the country complicating that decision-making process. Since Covid activity is currently high and newly approved or authorized Covid vaccines are starting to show up in pharmacies and doctors’ offices, let’s start there.
If you’re eligible for only a single Covid shot per year: Young children getting their first Covid shots need two doses of Moderna’s pediatric vaccine or three doses of the Pfizer version. The only other people entitled to get more than one Covid shot per year are people aged 65 and over, who can get two in a 12-month period, and people who have some illnesses that compromise their immune system. People who are moderately or severely immunocompromised can get multiple Covid shots per year, with the agreement of their doctors, though they should wait at least two months between doses, the CDC says.
If you can only get one, this year poses a dilemma. Do you get it now, or do you wait until later in the fall in the hopes you’d get more protection over the winter? We’ve had Covid activity every winter since the SARS-CoV-2 virus emerged in the United States in 2020. And it’s perhaps easier to evade infection when restaurant patios are open and get-togethers can be outdoors than when cold weather descends and holiday travel is a priority.
Covid vaccines offer pretty durable protection against getting sick enough to require hospitalization, but the immunity they generate against getting sick at all is more short-lived. Still, some people hope the shots will protect them from any disease, at least for a while. Katelyn Jetelina is one of them. An infectious diseases epidemiologist who writes the popular Your Local Epidemiologist substack column, Jetelina admitted she’s struggled this year to figure out when to get her Covid shot.
“I know that with the vaccines, the primary purpose is [to prevent] severe disease. But I’m using them for their secondary purpose, to help reduce disruptions in my life, even if that’s imperfect and short term,” Jetelina said. “And so I’m thinking of it like: Might as well wait for that winter wave, which will coincide … with fun holiday activities that I don’t want to miss.”
She’s currently planning on getting both a Covid and a flu shot together, around Halloween.
But a number of the experts STAT spoke with suggested getting a Covid shot now makes a lot of sense — as long as you haven’t recently had Covid or another dose of Covid vaccine. The CDC recommends people wait at least three months after a bout of Covid before getting vaccinated, and it advises people to leave at least four months between Covid vaccinations.
Jetelina isn’t a fan of this three-month versus four-month intervals advice, saying it is overly complicated for the average vaccination seeker. “I cannot believe trying to figure it out if you’re the average Joe on the corner. I mean, it’s very confusing.”
But she’s the granddaughter of a 96-year-old, and is concerned about the Covid risk he currently faces, given the high levels of transmission right now. “I am suggesting that he gets it sooner rather than later,” she said. She’s also suggesting he get his flu shot a little later, though she acknowledged this could be a challenge; her grandfather no longer drives.
Even people who aren’t that old might want to book a Covid shot soon, said Florian Krammer, an influenza virologist at Mount Sinai’s Icahn School of Medicine in New York City.
“Right now there’s a lot of SARS-CoV-2 cases and so if people didn’t have SARS-CoV-2 in a while, it might be good to get a vaccine relatively quickly … because that reduces your chances of getting infected or getting symptomatic disease in the near future,” Krammer said.
But might that not leave a person less protected during the winter, when Covid is also likely to circulate? “That is a valid concern. It’s hard to weigh the risks and say: ‘Okay, it would be better to take a risk now and be better protected later versus better protected now, and maybe less well protected later,’” he admitted. “I think to make these calculations … in a quantitative way, that would be really hard.”
That said, Krammer plans to get a Covid shot soon.
If you are immunocompromised or aged 65 and older: The timing decision is easier for people in these categories. The CDC, on the recommendation of its expert panel, the Advisory Committee on Immunization Practices, allows these people to get more than one shot a year. So if you’re 65 or older, a Covid shot in early September could be followed by another at some point early in the new year.
Michael Osterholm, director of the University of Minnesota’s Center for Infectious Disease Research and Policy, who is eligible for two shots, didn’t wait for the arrival of the updated Covid boosters. He opted instead to get one of the previous iterations of the vaccines about a month ago, because of the high levels of Covid transmission this summer. He’ll get one of the new shots later in the winter.
The challenge of deciding when to get Covid shots stems from the fact that the SARS-2 virus does not yet follow a seasonal pattern. (Will it ever? We’ll know when we know.) So while the Food and Drug Administration and the CDC have been basing the Covid vaccination effort on the annual flu shot campaign — and trying to synchronize the two — the reality is that the early September launch of Covid vaccination efforts may make sense from a delivery point of view, but not necessarily in a way that provides people with the best shot at being protected, the experts admitted.
“I think it’s complicated in general right now because influenza and SARS-CoV-2 behave differently,” Krammer said.
How to time your flu shot: If you want a Covid booster soon and you want to get your flu shot at the same time, you probably won’t be getting as much protection from the latter as you might if you timed it differently. That said, better early than never, Krammer said.
If you’re willing to book separate Covid and flu vaccination appointments, waiting a while for your flu shot makes sense. The CDC recommends that you get your flu shot by the end of October.
Though influenza activity was non-existent in the first winter of the Covid pandemic, and unusually early in 2022-2023 — the first year in the Covid era with a true flu season — there is a degree of predictability about when flu activity occurs in our part of the world. Flu is a winter illness, with transmission often peaking in the period from late December until mid-to-late February. (Some years the peak comes a little earlier; some years there is a second peak, sometimes in March.)
Like Covid vaccines, flu shots are better at preventing serious illness than they are at blocking infection entirely. And the immunity they generate declines over time.
“What we need to communicate is that these vaccines will keep you from severe illness and death. And they do very well for that,” said Kanta Subbarao, a professor of microbiology at Laval University in Quebec City.
“What I think that the public wants, and is fed up with vaccines because they think they’re not getting, is protection from infection. And that is true for flu vaccines. It’s true for the Covid vaccines. So the messaging has to be that you take these vaccines to keep yourself from getting severely ill — ill enough to require hospitalization, or to have complications, and so on.”
Subbarao, who is the former chair of the committee that advises the World Health Organization on Covid vaccine composition, plans to get a Covid booster as soon as Canada makes the shots available. But she’ll wait to get a flu shot.
“What I want is protection from November to March. And I think we get six months of protection from flu [shots],” she said. “And so if I want to be protected from November to March, then what I would say is that I think I could get vaccinated in late September or October.”
Monto, who has studied influenza for decades, gets his flu shot in late October. Osterholm recommends holding off — if you can — until flu is actually circulating where you live.
“I urge people to wait until we start seeing flu activity in the community and not just sporadic cases but sustained transmission,” he said. “I realize that’s a challenge to get scheduled at that point. But at the same time, you don’t want to lose the protection you have from the vaccine in its earliest days after administration compared to what may be a 20% to 50% reduction over the winter season from the time you got the vaccine.”
That approach, however, requires you to pay attention and be able to move quickly when the time comes. And recall, it takes about two weeks after getting a flu shot for the vaccine’s protection to really kick in. “You can get caught flat-footed if the virus does start circulating early,” Hensley noted.
Now about RSV vaccine: With the exception of pregnant people (more on them in a bit), RSV vaccines are available for older adults only. Two of the three available vaccines — Pfizer’s Abrysvo and Moderna’s mResvia — are currently licensed for people 60 and older; GSK’s Arexvy is licensed for that age group as well as for people aged 50 to 59 who are at high risk of serious illness if they catch RSV. They are all new vaccines: The GSK and Pfizer were licensed last year, the Moderna one followed in May.
There are a couple of hitches with these vaccines, which means that substantially fewer people are eligible to get one of them this fall.
For starters, it’s not yet known how often people will need to be re-vaccinated, though it is clear that for at least the GSK and Pfizer vaccines, annual vaccination is not needed. So any older adult who has already received an RSV shot isn’t eligible to get another at this time. The other twist relates to a recent change in CDC policy that will affect who can get these vaccines covered by their health insurance. At a meeting in late June, the agency’s vaccines advisory committee, ACIP, changed its recommendation on who should get an RSV shot. Previously the policy had been that people 60 and older could get a shot, if they and their doctors agreed it was needed. Doctors complained this approach, known as shared decision-making, was too confusing and time-consuming, so ACIP revisited the policy.
The new policy recommendations, which the CDC adopted, suggest that people 75 and older should get an RSV shot — if they haven’t had one already. People aged 60 to 74 who have health conditions that increase their risk of becoming seriously ill from RSV infection should also get one, if they haven’t yet. Those health conditions include chronic heart or lung diseases, severe diabetes, or a weakened immune system; people living in long-term care also qualify here.
Anyone else in the 60-74 age category can get one, but without a recommendation from the ACIP and CDC, they will likely find the hefty cost of the shots — about $300 plus administration fees — will come out of their own pockets.
The ACIP decided not to make a recommendation about at-risk people aged 50 to 59, saying the panel had too little data at this point on which to base a recommendation, a move that surely disappointed manufacturers that hoped to expand the pool of people getting these shots.
RSV season typically begins in the fall and peaks in the winter. The CDC recommends that people who are getting an RSV shot do so in late summer or early fall.
What should pregnant people do?: Pfizer’s Abrysvo is also licensed for use in pregnant people, to protect their babies from RSV after birth. The CDC recommends that pregnant people who will be giving birth during RSV season — from September through January in most parts of the U.S. — get a shot between week 32 and week 36 of each pregnancy.