A wedding in Oklahoma that resulted in 15 vaccinated guests becoming infected with the coronavirus. Loud July 4th celebrations that dispersed the virus from Provincetown, Massachusetts, in dozens of places across the country.
As Delta variant spreads across the country, reports so-called "revolutionary" infections in vaccinated people have become more and more frequent, including, more recently, when at least six Texas Democrats and one help from speaker Nancy Pelosi tested positive.
The highly contagious variant, combined with the near absence preventive restrictions, is fueling a rapid increase in cases in all states, and hospitalizations in almost all. It now accounts for about 83% of diag infections.Nosticated in the United States.
But worrying as the trend may seem, breakthrough infections in vaccinated people are still relatively rare. , say experts, and even more those that cause serious illness, hospitalization or death. More than 97% of people hospitalized for Covid-19 are not vaccinated.
" The message Remember, if you're vaccinated, you're protected, ”said Dr. Celine Gounder, infectious disease specialist at Bellevue Hospital Center in New York. "You are not going to end up with serious illness, hospitalization or death.
Reports of breakthrough infections should not be interpreted as meaning that vaccinesare not working, Dr Anthony S. Fauci, the Biden administration 's senior pandemic adviser, said Thursday.
"This does not mean in no case you're dealing with an unsuccessful vaccine, ”he said. “The success of the vaccine is based on the prevention of the disease.
However, vaccinated people can contract infections, mostly asymptomatic to mild. This may come as a surprise to vaccinated Americans, who often assume that they are completely free from the virus. And breakthrough infections raise the still unresolved possibility that vaccinated people could spread the virus.
With the virus on the rise in much of the country, some scientists say it is time for vaccinated people to consider wearing face masks. indoors and in crowded spaces like subways, malls, or concert halls - a recommendation that goes beyond current guidance from the Centers for Disease Control and Prevention, which recommend masking only for unvaccinated people.
The agency does not plan to change its guidelines unless it 's 'there is a significant shift in science, said ial federal official speaking undercoverrt of anonymity because he was not authorized to comment on the subject.
Agency advice already gives local leaders the latitude to adjust their policies based on transmission rates in their communities, he added. Citing the rise of the Delta variant, health officials in several California jurisdictions are already urging a return to interior masking; Los Angeles County is requ iring it.
"Seat belts reduce risk, but we must always drive safely," said Dr. Scott Dryden -Peterson, infectious disease physician and epidemiologist at Brigham & Women 's Hospital in Boston. "We are still trying to figure out what it is to 'drive safely' in the Delta era, and what we should do.ary. "
The uncertainty about Delta's results in part from how it differs from previous versions of the coronavirus. Although its mode of transmission either the same - it's inhaled, usually in indoor spaces - Delta is thought to be about twice as contagious as the original virus.
Significantly , early evidence also suggests that people infected with the Delta variant may wear roughly a a thousand times more viruses than those infected with the original virus. While that doesn't seem to mean they get sicker, it probably means they're more contagious and for longer.
Dose matters too : a vaccinated person exposed toa low dose of the coronavirus may never or not be significantly infected. A vaccinated person exposed to extremely high viral loads of the Delta variant is more likely to have their immune defenses overwhelmed.
The problem worsens as community transmission rates are increasing as dose and number exposures increase. Vaccination rates in the country have stalled, with less than half of Americans are fully immunized, leaving the virus with plenty of room to spread.
Unvaccinated people "don't take precautions, for the most part, and that's what makes everyone tick," said Dr Eric J. Rubin, medical specialist infectious diseases and editor of New England Daynal of Medicine. "We are all sensitive to the behavior of anyone in this epidemic. The coronavirus epidemic ›
Dr. Gounder likened the protection offered by vaccines to a golf umbrella that keeps people dry during a rainstorm." But if you're in a hurricane you're still going to get wet, she said. "This is the kind of situation the Delta variant created, where there's still a lot of community spread.
For the average vaccinated person, a breakthrough infection is probably harmless, causing little or no symptoms. But scientists fear that a few people vaccinated.infants who become infected can develop a long Covid, a poorly understood constellation of symptoms that persists after the active infection resolves. Image Masked travelers passing through Union Station in Los Angeles, where the mask warrant was reinstated on July 17. Credit ... Mario Tama / Images
Delta's ability to bypass the immune system caused quite a stir. In fact, all existing vaccines appear to be able to prevent serious disease and variant death (although questions have recently been raised about the Johnson & Johnson vaccine). In laboratory studies, Delta was actually shown to be a milder threat than Beta, thea variant first identified in South Africa.
The fact that a vaccinated person is infected can affect how the antibodies have increased after vaccination, the potency of these antibodies against the variant and whether the level of antibodies in the person's blood has decreased since the vaccination.
In In any case, the immune defenses primed by the vaccines should recognize the virus soon after infection and destroy it before significant damage occurs.
" This is what explains why people get infected and why people don't get seriously ill, "said Michel C. Nussenzweig, immunologist at Rockefeller University in New York. "It's almost inevitable, unless you give people very frequent reminders." variant are more common or more likely to spread toother people. The C.D.C. recorded around 5,500 hospitalizations and deaths among those vaccinated, but it is do not track more benign breakthrough infections .
Additional data is emerging from the Covid -19 Sports and Society Workgroup, a coalition of professional sports leagues that work closely with the CDC The group's sports teams test more than 10,000 people at least daily and sequence all infections, according to Dr. Robby Sikka, a doctor who worked with the Minnesota Timberwolves in the NBA.
Breakthrough infections in the leagues appear to be more common with the Delta variant than with Alpha, the variant first identified in Britain, he said. As you would expect, vaccines significantly reduce the severity and duration of illness, with players returning less than two weeks after being infected, compared to nearly three weeks earlier in the pandemic.
But while sick, players carry very large amounts of the virus for seven to 10 days, compared to two or three days in people infected with Alpha, said Dr Sikka. Infected players are required to quarantine themselves, so the project has not been able to determine if they have spread the virus to others - but it is likely they would. , he added.
"If they are unwillingly reintegrated into society, I think you will spread from there 'vaccinated individuals,' he added. "They don't even recognize they have Covid because they think they are vaccinated.
Elyse Freitas was shocked to discover that 15 vaccinated people were infected during her marriage. Dr Freitas, 34, a biologist at the University of Oklahoma, said she had been very cautious throughout the pandemic and had already postponed her marriage once. But after much deliberation, she performed the wedding indoors on July 10.
Based on the symptoms, Ms. Freitas believes that the initial infection occurred during a bachelorette party two or so days before the wedding, when a dozen vaccinated people unmasked themselves in bars in downtown Oklahoma City; seven of them then tested positive. Eventually, 17 wedding guests were infected, almost all with mild symptoms.
"Looking back, I should have paid more attention vaccination rates in Oklahoma and the emergence ofDelta variant and I have adjusted my plans accordingly, ”she added. "We must continue to be vigilant and careful. Image A Covid treatment area of a hospital last week in Springfield, Missouri, where cases have increased. Credit ... Nathan Papes / The Springfield News-Leader, via Associated Press
An epidemic in Provincetown, Massachusetts illustrates how quickly a cluster can grow, under the right conditions. During its famous July 4th celebrations, the small town hosted more than 60,000 revelers unmasked, dancing and mingling at crowded bars and home parties.
The crowds this year were much bigger than usual, said Adam Hunt , 55, an executive who has lived in Provincetown part-time for about 20 years. But bars and clubs only opened when they were allowed to, said Hunt: “We thought we were doing the right thing. We thought we were fine. "
Mr. Hunt was not infected with the virus, but several of his vaccinated friends who had come from Places as far away as Hawaii and Alabama have tested positive after returning. In total, the cluster has grown to at least 256 cases - including 66 visitors from other states - about two-thirds of those vaccinated, according to Steve Katsurinis, president of the Provincetown Board of Health.
"I didn't expect people to be vaccinatedare becoming positive at the rate they were, "Katsurinis said. Provincetown has moved quickly to contain the outbreak, reinstating a mask warrant and stepping up testing. It performs 250 tests a day, up from around eight per day before July 1, Katsurinis said.
Health officials should also help the public understand that vaccines are what they do. 'they're supposed to do - keep people from getting seriously ill, said Kristen Panthagani, a geneticist at Baylor College of Medicine who runs a blog explaining complex scientific concepts.
News reports often cite the percentage of hospitalized people who are vaccinated as a measure of vaccine effectiveness, but this numberIt's easy to misinterpret, she warned. The proportion of vaccinated people who become ill will increase over time as the vaccinated population increases and fewer people are hospitalized for Covid-19, she noted.
And as more people are vaccinated, reports of groundbreaking infections will also increase.
"The effectiveness of vaccine is not 100%, it never is, "she said. “We also shouldn't expect Covid vaccines to be perfect. This is too high an expectation. "