What the Cape Cod Holidaygoers Can Teach Us
They thought they were fully vaccinated, and came to play. We are learning that even with vaccinations, transmission and infections occur. We still don't know if the Delta variant can be transmitted to children or others, even if those infected are asymptomatic themselves.
As of Thursday, 882 people were tied to the Provincetown outbreak. Among those living in Massachusetts, 74% of them were fully immunized, yet officials said the vast majority were also reporting symptoms. Seven people were reported hospitalized.
The initial findings of the investigation led by the Massachusetts Department of Public Health, in conjunction with the Centers for Disease Control and Prevention, seemed to have huge implications.
Before Provincetown, health officials had been operating under the assumption that it was extraordinarily rare for a vaccinated person to become infected with the virus. And if they did, they probably wouldn't end up passing it on to others, such as children too young to qualify for the vaccine or people who were medically vulnerable.
Vaccines definitely help lessen the symptoms in some, but the tradeoff appears to be the greater transmission rate.
But that assumption had been based on studies of earlier versions of the virus. Delta was known for its "hyper-transmissibility," or as one former White House adviser put it "COVID on steroids."
"What has changed is the virus," said Dr. Anthony Fauci, the nation's top infectious disease expert and Biden's chief medical adviser.
When a vaccinated person gets infected with delta -- called a "breakthrough infection" -- "the level of virus in their nasopharynx is about 1,000 times higher than with the alpha variant," Fauci said in an interview Wednesday with MSNBC
The idea that vaccines halt transmission of the virus was largely behind the CDC's decision in May suggesting vaccinated people could safely go without their masks indoors and in crowds, even if others were unvaccinated.
I think we got overconfident as a country in the power of the vaccines, and the manufacturers are telling us that over time, the vaccines lose some of their effectiveness. Booster shots for the new vaccines are already being explored. Let's be smart and remember that limiting exposing others, even if you are asymptomatic and vaccinated yourself, is the safest option for all. We are not out of the woods yet, and we are learning that the higher transmission rates of the delta variant are not necessarily caused by the unvaccinated, but also by the overconfident vaccinated, like those vacationing at the Cod on the Fourth of July weekend...
#NoBlameNoShameLet'sJustBeatThisThing
"In recent days I have seen new scientific data from recent outbreak investigations, showing that the delta variant behaves uniquely differently from past strains of the virus that causes COVID 19," CDC Director Rochelle Walensky told reporters Tuesday announcing the new recommendations.
"Information on the delta variants from several states and other countries, indicate that in rare occasion some vaccinated people infected with a delta variant after vaccination may be contagious and spread the virus to others," she added. "This new science is worrisome and unfortunately warrants an update to our recommendation."
When asked to release the new evidence, the CDC said more details would be released on Friday.
But Walensky hinted that the biggest driver was new unpublished research on a person's "viral load" -- the amount of virus in a person's nasal passages -- being considerably high even after being vaccinated with a U.S.-approved vaccine.
"What we've learned … is that when we examine the rare or breakthrough infections and we look at the amount of virus in those people, it is pretty similar to the amount of virus in unvaccinated people," she said.
It's like with antibiotics, maybe. The CoVid virus is adjusting to the vaccines and morphing into a new threat that can "beat" the protections we think we have. By lessening the symptoms of infection in the majority, we maybe have created variants that are not only more contagious but that perhaps post greater risks to those who do become infected by the newer variants. Scientific study continues, as more and more human subjects present for testing and treatment. Hold on to your conclusions, friends, it appears the worldwide experiment on how to best combat this supervirus still rages...
Vaccines, isolation when indoors, and masks are tools we can use to fight, but taken alone, it appears none are capable of defeating this evolving virus yet.
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Antibody-dependent enhancement and SARS-CoV-2 vaccines and therapies
Nature Microbiology volume 5, pages 1185–1191 (2020)
Abstract
Antibody-based drugs and vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are being expedited through preclinical and clinical development. Data from the study of SARS-CoV and other respiratory viruses suggest that anti-SARS-CoV-2 antibodies could exacerbate COVID-19 through antibody-dependent enhancement (ADE). Previous respiratory syncytial virus and dengue virus vaccine studies revealed human clinical safety risks related to ADE, resulting in failed vaccine trials. Here, we describe key ADE mechanisms and discuss mitigation strategies for SARS-CoV-2 vaccines and therapies in development. We also outline recently published data to evaluate the risks and opportunities for antibody-based protection against SARS-CoV-2
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