On Saturday morning, I finally rolled up my sleeve for the vaccine I’d been waiting for all summer: my annual flu shot, a technological marvel that I want to receive every fall.
In times without a pandemic, the flu vaccine is a hot fall product that holds a coveted place in the public health spotlight. Recently, however, the shot has been dwarfed by the importance of its COVID-blocking cousins, fueled by debates over boosters and mandates. It’s also been a while since we had to deal directly with the flu. Thanks to the infection prevention measures the world took at the beginning of the pandemic to combat SARS-CoV-2, many other respiratory viruses have disappeared. Last winter we had “no flu season at all,” says Florian Krammer, virologist at the Icahn School of Medicine on Mount Sinai. The human attention span is short; the short sabbatical of the flu may at an inopportune time cleared it from our minds.
An absent virus isn’t necessarily an extinct one, and the return of the flu has always been a matter of if, not if. And with the weather getting cooler, experts fear that skipping a sick season could come at a cost if we don’t raise our flu shields again. Immune defense can rust and crumble; Flu viruses may return to find a number of hosts more vulnerable than before, especially now that kids are back in classrooms and mask boredom continues to rise across the country. “I worry we’re not careful,” said Hana El Sahly, an infectious disease doctor and vaccine expert at Baylor College of Medicine. So flu shots are especially valuable this year– perhaps more than it has been in a long time.
Concerns about coming back to the flu are not new. As early as February, when I first wrote about the lull in flu cases, experts already warned that truancy of the bugs could make them more unpredictable. Flu viruses, already a known threat to our immune system, distribute less easily than SARS-CoV-2, which made it easier to stamp them out with masks, physical distancing, school closings, and international travel bans, even if compliance was spotty. Cases around the globe crashed. But “nobody expected the flu to go away forever,” said Mary Krauland, an infectious disease modeller at the University of Pittsburgh.
Now we are swaying on the edge of the cold turn of the year as Pandemic Restrictions grow and shrink. Many experts suspect that one flu season may be worse than the previous one there the previous one was so mild. The threshold for an outbreak this year could very well be lower. “I’m probably 60-40: 60 we’ll have a season, we’ll not be 40,” said Richard Webby, an influenza expert at St. Jude Children’s Research Hospital in Tennessee. “My gut feeling is that when it comes back there will be a little more punch.”
The absence of the flu had positive effects. It will save health workers, hospitals and the general population a second winter sickness decline, on top of an already overwhelming pandemic. Our non-flu season also starved the hosts’ viruses, where they can multiply, change, and persist. Some experts hope that certain lines may have been completely pushed out of existence, or at least have come close. This could mean that in the future we will have fewer flu flavors and will have to vaccinate against them, although their disappearance is not yet certain.
But the past season did not leave our sometimes forgetful immune cells with an important annual reminder: Influenza viruses do exist and can cause serious damage to the body. Reasonable Well Last winter’s flu shot certainly shook our body’s memories. But without the extra alarms caused by the actual illness – which occurs during normal times many millions of the people in the United States alone – people’s bodies may not be as fit as they should be. “You really need the seasonal waves to boost population immunity and prevent large outbreaks,” said Helen Chu, a doctor and immunologist at the University of Washington.
Infants and young children may be particularly at risk this year, as a larger number of them than usual may never have come into contact with a flu virus. Schools are reopened, many without masking requirements, which increases the risk for both children and those who interact with them. “When it comes to influenza,” said El Sahly, “children are the transmission engine in the community.” A preview of this pattern unfolded as early as spring and summer with the respiratory syncytial virus, another airway-loving pathogen that hits children particularly hard . Like flu viruses, RSV almost evaporated last winter but was able to sneak back into the American population in early April when many COVID-19 restrictions were eased.
Two youngest Models by Krauland and her colleagues at the University of Pittsburgh, published in preprint papers last month, indicate how much it costs to miss our annual immune boost. Flu cases and hospital admissions, the studies said, could both see a surge this year, possibly beyond the typical seasons – an added burden the pandemic-ridden health system can hardly afford. This is especially likely if the COVID precautions keep falling away or if we are affected by a particularly contagious flu virus that our body does not recognize well. Worryingly, other experts pointed out that influenza viruses and SARS-CoV-2 could even invade some of the same people at the same time, causing very serious flare-ups in those at risk.
These are not things that can be taken for granted, said Kyueun Lee, who led one of the studies. Our social behavior is still not at the pre-pandemic level; even temporary masking, distancing and the like could put a damper on the upcoming flu campaign. In Australia, a nation that countries in the global north usually consider epidemic stage, flu levels have stayed pretty low, which could be a good sign for the United States, told me Ibukun Kalu, a pediatric infectious disease doctor at Duke University (though she added that the American approach to COVID containment is “largely” different from the Australian one). Case numbers could be somewhere between last year’s surprising low and the pre-pandemic norm.
We also have an exceptionally powerful but underutilized tool in our arsenal: an immunity-boosting vaccine. The flu shot usually just reaches about half of the US population, but Lee believes it is important to increase that percentage this year as it could help close some of the rifts COVID mitigations have left in our anti-flu armor. “Getting a flu vaccine this season can be especially important,” wrote Lynnette Brammer, who leads the CDC’s influenza surveillance team, in an email. But there is one more catch. Monitoring centers located around the world are normally able to many thousands of viral genome sequences to get a good read on what versions of the flu virus are floating around – which ones may be ready to reappear on occasion. Scientists gain this wealth of data when selecting varieties for annual intake. But last winter this genetic source dried up. “It’s hard to decide if you don’t have a clear picture of what’s out there,” Krammer told me.
But there was enough Data to make an informed decision reassured me experts. “The game is always a game of chance,” said El Sahly, who Member of the committee who advise the FDA on the final vaccine formulation. “Even high transmission in advance does not guarantee that the variety selection will be just right.” In general, the effectiveness of influenza vaccination against disease is a factor about 60 percent. But like most other vaccinations, the vaccine is excellent at containing the disease Heaviness of symptoms and keeping people out of the hospital; even a slightly unsuitable vaccine could have a huge impact on the viruses’ effectiveness. “No matter what, it’ll protect you at least a little,” Chu said.
Influenza vaccinations are also a good way to hedge bets. The standard “tetravalent“Formulation contains safe, inactivated representatives of four branches on the flu tree: H1N1 and H3N2, subtypes belonging to the influenza A family, and B / Victoria and B / Yamagata, lines of the influenza B family. Influenza A viruses generally change faster than their B-list cousins, so these ingredients change more frequently. The recording I got this weekend contained two updates, compared to last year’s recipe which will hopefully prepare me better for the flu stress du jour. (Kalu pointed out another benefit: we’re still waiting for the official go-ahead for COVID-19 vaccines for those under 12, but the flu shot is now available for children from six months.)
No matter how the flu hits us this winter, my new vaccine is an insurance policy: Either way, I’m better protected than I was. Recording was easy too. I was able to get an appointment on the first try; The injection itself, which was free and painless, only took a second at my local CVS. (By the way, flu and COVID-19 vaccinations can be in the same time.) It was clearly the awakening that my body needed: within hours my arm was a little swollen; eventually, the lymph nodes next to it did so too, probably as they were filling with hordes of grumpy, flu-sensitive immune cells, some of which likely woke up from a two-year slumber. I felt a little bit painful, a little bit tired. I felt so much better than before.
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Thank You For Reading!
Reference: www.theatlantic.com
