New boosters add limited protection against Covid-19 illness, first real-world study shows | CNN





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Updated Covid-19 boosters that carry instructions to arm the body against currently circulating Omicron subvariants offer some protection against infections, according to the first study to look at how the boosters are performing in the real world. However, the protection is not as high as that provided by the original vaccine against earlier coronavirus variants, the researchers say.

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, called the new data “really quite good.”

“Please, for your own safety, for that of your family, get your updated Covid-19 shot as soon as you’re eligible to protect yourself, your family and your community,” Fauci said at a White House briefing Tuesday.

Uptake of the bivalent boosters, which protect against the BA.4/5 subvariants as well as the original virus strain, has been remarkably slow. Only 11% of eligible Americans have gotten them since they became available in early September.

The new study found that the updated boosters work about like the original boosters. They protect against symptomatic infection in the range of 40% to 60%, meaning that even when vaccine protection is its most potent, about a month after getting the shot, people may still be vulnerable to breakthrough infections.

That’s in about the same range as typical efficacy for flu vaccines. Over the past 10 years, CDC data shows, the effectiveness of the seasonal flu vaccines has ranged from a low of 19% to a high of around 52% against needing to see a doctor because of the flu. The effectiveness varies depending on how similar the strains in the vaccine are to the strains that end up making people sick.

The authors of the new study say people should realize that the Covid-19 vaccines are no longer more than 90% protective against symptomatic infections, as they were when they were first introduced in 2020.

“Unfortunately, the 90% to 100% protection was what we saw during like pre-Delta time. And so with Delta, we saw it drop into the 70% range, and then for Omicron, we saw it drop even lower, to the 50% range. And so I think what we’re seeing here is that the bivalent vaccine really brings you back to that sort of effectiveness that we would have seen immediately after past boosters, which is great. That’s where we want it to get,” said Dr. Ruth Link-Gelles, an epidemiologist at the US Centers for Disease Control and Prevention.

“This protection is not 100%, but it is something,” Link-Gelles said. “Especially going into the holidays where you’re likely to be traveling, spending time with elderly relatives, with vulnerable people. I think having some protection from infection and therefore some protection from infecting your loved one is better than having no protection at all.”

Link-Gelles says it also means that people should continue to adopt a layered approach to protection, utilizing rapid tests, good-quality masks and ventilation as a comprehensive approach, rather than relying on vaccines alone.

“This should be sort of one of the things in your toolbox for protecting yourself and your family,” she said. “Personally, we’re my family is all vaccinated up to date, but I think if we go to the airport tomorrow, we’ll be wearing our N95 [masks] because we’re seeing elderly relatives this weekend. And while we of course trust the vaccines, and I’m not super worried about a mild infection in myself or my healthy husband, we certainly would not want to infect his grandmother.”

Link-Gelles added that she expects that vaccine protection against severe outcomes from Covid-19, like hospitalization and death, will be higher, but that data isn’t in yet.

The study, which was led by CDC scientists, relied on health records from more than 360,000 tests given at nearly 10,000 retail pharmacies between Sept. 14 and Nov. 11, a period when the BA.4 and BA.5 subvariants were causing most Covid-19 infections in the US. The study included people ages 18 and up who had Covid-19 symptoms and were not immunocompromised.

The study looked at how effective the boosters were in two ways: Researchers calculated a value called absolute vaccine effectiveness, which compared the odds of symptomatic infection in people who received bivalent boosters with those who reported being unvaccinated. They also calculated relative vaccine effectiveness, which looked at the odds of symptomatic infection in people who received updated bivalent boosters compared with those who had two, three or four doses of the original single-strain vaccine.

Compared with people who were unvaccinated, adults 18 to 49 who had gotten bivalent boosters were 43% less likely to get sick with a Covid-19 infection. Older adults, who tend to have weaker immune function, got less protection. Those ages 50 to 64 were 28% less likely, and those ages 65 and up were 22% less likely to get sick with Covid-19 than the unvaccinated group.

The relative vaccine effectiveness showed the added protection people might expect on top of whatever protection they had left after previous vaccine doses. If a person was two to three months past their last vaccine dose, the bivalent boosters added an average of 30% protection for those who were ages 18 to 49, 31% more protection if they were 50 to 64, and 28% more protection if they were 65 or older. At 3 months after their last booster, people ages 50 and older still had about 20% protection from Covid-19 illness, CDC data show. So overall, the updated boosters got them to around 50% effectiveness against symptomatic infection.

If a person was more than eight months away from their last vaccine dose, they got more protection from the boosters. But Link-Gelles said that by eight months, there was little protection left from previous shots against Omicron and its variants, meaning the vaccine effectiveness for this group was probably close to their overall protection against infection.

Those ages 18 to 49 who were eight months or more past their last dose of a vaccine had 56% added protection against a Covid-19 infection with symptoms; adults 50 to 64 had 48% added protection, and adults over 65 had 43% added protection, on top of whatever was left from previous vaccinations.

John Moore, an immunologist and microbiologist at Weill Cornell Medicine, said it boils down to the fact that that boosters will probably cut your risk of getting sick by about 50%, and that protection probably won’t last.

“Having a booster will give you some additional protection against infection for a short term, which is always what we see with a booster, but it won’t last long. It’ll decline, and it will decline more as the more resistant variants spread,” said Moore, who was not involved in the new research.

The immunity landscape in the United States is more complex than ever. According to CDC data, roughly two-thirds of Americans have completed at least their primary series of Covid-19 vaccines. And data from blood tests shows that almost all Americans have some immunity against the virus, thanks to infection, vaccination or both.

A new preprint study from researchers at Harvard and Yale estimates that 94% of Americans have been infected with the virus that causes Covid-19 at least once, and 97% have been infected or vaccinated, increasing protection against a new Omicron infection from an estimated 22% in December 2021 to 63% by November 10, 2022. Population protection against severe disease rose from an estimated 61% in December 2021 to around 89%, on average, this November.

All of this means the US is in a better spot, defensively at least, than it ever has been against the virus – which is not to say that the country couldn’t see another Covid-19 wave, especially if a new variant emerges that is very different from what we’ve seen, if immunity continues to wane or if behavior shifts dramatically.



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Is It Flu, RSV or COVID? Experts Fear the ‘Tripledemic’


Oct. 25, 2022 – Just when we thought this holiday season, finally, would be the back-to-normal one, some infectious disease experts are warning that a so-called tripledemic – influenza, COVID-19, and RSV – may be in the forecast.

The warning isn’t without basis. 

  • The flu season has gotten an early start. As of Oct. 21, early increases in seasonal flu activity have been reported in most of the country, the CDC says, with the southeast and south-central areas having the highest activity levels. 
  • Children’s hospitals and emergency departments are seeing a surge in children with RSV.
  • COVID-19 cases are trending down, according to the CDC, but epidemiologists – scientists who study disease outbreaks – always have their eyes on emerging variants. 

Predicting exactly when cases will peak is difficult, says Justin Lessler, PhD, a professor of epidemiology at the University of North Carolina at Chapel Hill. Lessler is on the coordinating team for the COVID-19 Scenario Modeling Hub, which aims to predict the course COVID-19, and the Flu Scenario Modeling Hub, which does the same for influenza.

For COVID-19, some models are predicting some spikes before Christmas, he says, and others see a new wave in 2023. For the flu, the model is predicting an earlier-than-usual start, as the CDC has reported.  

While flu activity is relatively low, the CDC says, the season is off to an early start. For the week ending Oct. 21, 1,674 patients were hospitalized for flu, higher than in the summer months but fewer than the 2,675 hospitalizations for the week of May 15, 2022. 

As of Oct. 20, COVID-19 cases have declined 12% over the last 2 weeks, nationwide. But hospitalizations are up 10% in much of the Northeast, The New York Times reports, and the improvement in cases and deaths has been slowing down. 

As of Oct. 15, 15% of RSV tests reported nationwide were positive, compared with about 11% at that time in 2021, the CDC says. The surveillance collects information from 75 counties in 12 states. 

Experts point out that the viruses — all three are respiratory viruses —  are simply playing catchup. 

“They spread the same way and along with lots of other viruses, and you tend to see an increase in them during the cold months,” says Timothy Brewer, MD, professor of medicine and epidemiology at UCLA.

The increase in all three viruses “is almost predictable at this point in the pandemic,” says Dean Blumberg, MD, a professor and chief of pediatric infectious diseases at the University of California Davis Health. “All the respiratory viruses are out of whack.” 

Last year, RSV cases were up, too, and began to appear very early, he says, in the summer instead of in the cooler months. Flu also appeared early in 2021, as it has this year. 

That contrasts with the flu season of 2020-2021, when COVID precautions were nearly universal, and cases were down. At UC Davis, “we didn’t have one pediatric admission due to influenza in the 2020-2021 [flu] season,” Blumberg says. 

The number of pediatric flu deaths usually range from 37 to 199 per year, according to CDC records. But in the 2020-2021 season, the CDC recorded one pediatric flu death in the U.S.

Both children and adults have had less contact with others the past 2 seasons, Blumberg says, “and they don’t get the immunity they got with those infections [previously]. That’s why we are seeing out-of-season, early season [viruses].” 

Eventually, he says, the cases of flu and RSV will return to previous levels. “It could be as soon as next year,” Blumberg says. And COVID-19, hopefully, will become like influenza, he says.

“RSV has always come around in the fall and winter,” says Elizabeth Murray, DO, a pediatric emergency medicine doctor at the University of Rochester Medical Center and a spokesperson for the American Academy of Pediatrics. This year, children are back in school and for the most part not masking, she says. “It’s a perfect storm for all the germs to spread now. They’ve just been waiting for their opportunity to come back.” 

Self-Care vs. Not

RSV can pose a risk for anyone, but most at risk are children under age 5, especially infants under age 1, and adults over age 65.  There is no vaccine for it. Symptoms include a runny nose, decreased appetite, coughing, sneezing, fever, and wheezing. But in young infants, there may only be decreased activity, crankiness, and breathing issues, the CDC says.

Keep an eye on the breathing if RSV is suspected, Murray tells parents. If your child can’t breathe easily, is unable to lie down comfortably, can’t speak clearly, or is sucking in the chest muscles to breathe, get medical help. Most kids with RSV can stay home and recover, she says, but often will need to be checked by a medical professional.

She advises against getting an oximeter to measure oxygen levels for home use. “They are often not accurate,” she says. If in doubt about how serious your child’s symptoms are, “don’t wait it out,” she says, and don’t hesitate to call 911.

Symptoms of flu, COVID, and RSV can overlap.  But each can involve breathing problems, which can be an emergency. 

“It’s important to seek medical attention for any concerning symptoms, but especially severe shortness of breath or difficulty breathing, as these could signal the need for supplemental oxygen or other emergency interventions,” says Mandy De Vries, a respiratory therapist and director of education at the American Association for Respiratory Care. Inhalation treatment or mechanical ventilation may be needed for severe respiratory issues.

Precautions

To avoid the tripledemic – or any single infection – Timothy Brewer, MD, a professor of medicine and epidemiology at UCLA, suggests some familiar measures: “Stay home if you’re feeling sick. Make sure you are up to date on your vaccinations. Wear a mask indoors.”



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