(Bloomberg) –
Anecdotes tell us what the data can’t do: People who have been vaccinated seem to catch the coronavirus at a surprisingly high rate. But how often is not clear exactly, nor is it certain how likely the virus is to spread to others. And now there is a growing concern that vaccinated people are more likely to develop serious illnesses than previously thought.
There is a lack of scientific studies with concrete answers, forcing public policy makers and business leaders to make plans based on fragmented information. While some are renewing mask mandates or delaying office reopening, others report a lack of clarity to stay on track. Anyone can feel like a mess.
“We have to be humble about what we know and what we don’t know,” said Tom Frieden, former director of the Centers for Disease Control and Prevention and president of the nonprofit Resolve to Save Lives. “There are a few things we can say definitively. The first is that this is a very difficult question to answer.”
In the absence of clear public health messages, vaccinated people are confused about how to protect themselves. Their vulnerability is an important variable, not only for public health officials trying to figure out, for example, when booster doses might be needed, but also making decisions about how to reverse reopening during a new wave of the virus. On a smaller scale, the unknowns left music fans unsure if watching a concert was a good idea and sparked another round of parental tension about what the school was like.
In place of the answers, a series of case studies have emerged that present slightly different pictures of the infection. Variables, such as when the studies were conducted, whether a delta variable was present, how many populations were vaccinated, and even what the weather was like at the time, make it difficult to compare results and infer patterns. It’s hard to say which data will ultimately carry more weight.
“It’s clear we’ve made more breakthroughs now,” said Monica Gandy, an infectious disease expert at the University of California, San Francisco. “We all know someone who has one. But we don’t have great clinical data.”
One of the most famous outbreaks of the disease among vaccinated people occurred in a small beach town in Provincetown, Massachusetts, where thousands of vaccinated and unvaccinated people gathered on dance floors and at house parties over the weekend of July 4 to celebrate the holidays — and what seemed Like a turning point in the epidemic. About three-quarters of the 469 infections were among people who had been vaccinated.
The authors of a case study for the Centers for Disease Control and Prevention (CDC) said this could mean they are just as likely to transmit Covid-19 as the unvaccinated. They cautioned, however, that as more people get vaccinated, they may also naturally be responsible for a higher proportion of Covid-19 infections, and this study wasn’t enough to draw any conclusions. The incident prompted the CDC to withdraw a recommendation it had made just a few weeks earlier and again urged it to hide vaccinations in certain places.
However, according to Gandhi, the specifics of that cluster of cases may have made the outbreak particularly bad.
“The prevalence of mild symptoms in this population was higher due to a lot of indoor activities (including intimacy), weekend rains, less time outdoors, and a mixture of people with a different vaccination status,” she said in an email. . .
Meanwhile, a recently released and much larger case study from the New York State Centers for Disease Control and Prevention (CDC) on infections found that numbers of superbugs have risen steadily since May, accounting for about 4% of cases by mid-July. . These researchers cautioned that factors such as the easing of public health restrictions and the emergence of a highly contagious delta variant could influence the results.
Another CDC case study, in Colorado, found that the infection rate in one county, Mesa, was significantly higher than the rest of the state, at 7% versus about 5%. The report indicated that this may be due to the prevalence of the delta variant there, but also indicated the ages of patients in Mesa and that low vaccination rates may have played a role.
Research conducted in Israel has strongly shown that immunity to the virus declines in the months following vaccination, and more recently, advanced cases may eventually lead to an increase in hospitalization.
Case studies and data from some states in the United States have also shown an increase in cases of piracy over time. But now that the delta variant has also increased, it’s hard to determine whether reduced immunity to any type of coronavirus infection is the cause, or whether the vaccines are not particularly effective against the delta variant. Of course you can do both. Behavioral change in vaccinated people could also be a factor, as they return to social gatherings, travel and eating indoors.
However, there are some hard facts at this point. People who have been vaccinated and infected with the virus are less likely to go to hospital, have a lower chance of intubation and die less quickly from the disease. There is no doubt that vaccines provide excellent protection. But most of the nation — nearly 30% of adults in the United States — is not immune, a fact that has conspired with a highly contagious Delta strain to push the country into another wave of outbreaks.
“The big picture here is that the vaccines are working and the reason for the sudden rise in the United States is that we’re not getting enough of the vaccine,” Frieden said.
To some extent, a hack is to be expected for any virus. In clinical trials, no vaccine for Covid has been 100% effective – even the best vaccines have never been. The more the virus spreads, the greater the chance of blisters developing. It is also common for some aspects of viral immunity to naturally decrease over time.
There are now simply more questions than answers. Does paranormal infection increase due to delta variant, weakened immunity, or return to normal life? Are vaccinated people more likely to develop serious illnesses than previously thought? How common is superinfection? For everyone’s guess.
“Overall, we should make public health decisions based on incomplete data,” Frieden said. “But there is a lot we don’t know.”
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