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Friday, August 13, 2021

What Is the True Vaccine Breakthrough Rate? The CDC Doesn’t Want You to Know

By refusing to track most vaccine breakthrough cases, the CDC arrived at the strange conclusion that collecting and providing less public health information is in the public's interest.

Image Credit: Flickr-Anthony Quintano | CC BY 2.0 (

Over a recent 12-day period the Milwaukee Brewers had nine players test positive for COVID-19.

While we don’t know the vaccination status of all the players, the team disclosed that most of the players were vaccinated for COVID-19, including former MVP Christian Yelich, who tested positive after experiencing mild flu-like symptoms.

“He did the right thing and reported those mild symptoms,” Brewers GM David Stearns said when it was announced Yelich was heading to the disabled list. “We got him a test … .The test returned positive and we got a confirmation test, which also came back positive.”

The Brewers are not an isolated example of Major League Baseball teams experiencing a rash of vaccination breakthroughs. Teams across the league have experienced similar problems, including the New York Yankees, who saw nine vaccinated players sidelined in May with COVID-19.

“This is the vaccine working,” CDC director Dr. Rochelle Walensky told ABC’s George Stephanopoulos at the time, adding that those who tested positive didn’t get a severe infection.

How Common Are Breakthroughs?

Walensky is correct that data show vaccinated individuals are far less likely to die or become hospitalized with COVID-19 than unvaccinated individuals.

Yet breakthrough cases also appear to be more common than the CDC, media, and public health officials suggest.

CNN says the breakthrough rate is less than one percent, while CBS News reports that 99.7 percent of new COVID cases involve unvaccinated people. The Hill, meanwhile, agrees that CDC data show less than one percent of fully vaccinated people get COVID.

How does this data mesh with anecdotal evidence that suggests many vaccinated people are contracting COVID? To be sure, it’s not just Major League Baseball teams who are seeing spikes of COVID cases among vaccinated individuals.

A recent outbreak in Provincetown, Massachusetts, for example found that the vast majority of COVID cases involved vaccinated individuals.

“Overwhelmingly, the affected individuals have been fully vaccinated for COVID-19,” Town Manager Alex Morse told NBC.

The outbreak, attributed to the rise of the Delta variant, was serious enough to prompt the CDC—which published a report on the outbreak—to reverse its recommendation that vaccinated individuals needn’t wear masks indoors.

But that wasn’t all. The CDC’s study also found, the Washington Post noted, individuals “carried as much virus in their noses as unvaccinated individuals.”

“High viral loads suggest an increased risk of transmission and raised concern that, unlike with other variants, vaccinated people infected with Delta can transmit the virus,” Walensky said.

All of this data suggests two important things.

First, COVID cases among vaccinated individuals appear to be higher than the “less than 1 percent” many claim. Two, vaccinated individuals appear quite capable of transmitting the virus to others, as Walensky states. Indeed, viral loads in nasal passages suggest they could transmit the virus at rates similar to unvaccinated carriers.

A Data Fiasco?

In the world today, we often hear that data is king. The problem is, the data have been a total mess throughout the pandemic. COVID, the New York Times recently observed, has shown the CDC is utterly broken.

Perhaps because of this, I decided to see how the CDC tracks and defines breakthrough cases.

“As of May 1, 2021, CDC transitioned from monitoring all reported vaccine breakthrough cases to focus on identifying and investigating only hospitalized or fatal cases due to any cause,” a statement says. “This shift will help maximize the quality of the data collected on cases of greatest clinical and public health importance.”

Does this mean the CDC isn’t tracking breakthrough cases anymore unless someone is hospitalized or dies? I asked the CDC for clarification. I didn’t hear back from them.

But if one goes to the CDC site, you’ll find information on vaccine breakthroughs that includes only hospitalizations and deaths. The figure—as of August 2—stands at 7,525, which is below the 9,245 breakthrough infections the CDC had documented as of April 26. (The CDC noted the true rate was higher, due to a lack of surveillance and testing.) Since then, three and a half months have eclipsed and nearly 70 million more people have been vaccinated—and the Delta variant has arrived in force.

Unfortunately, what the actual breakthrough rate is, nobody knows—because the CDC stopped collecting and publishing the data, choosing instead “to focus on identifying and investigating only hospitalized or fatal cases.”

In making this decision, the CDC arrived at the strange conclusion that public health would be better served by providing the public with less information.

Is the Breakthrough Rate Less Than 1%?

Because of this, the media are left guessing what the breakthrough rate is.

CNN points out that roughly half of US states report data on breakthroughs, and in those states official statistics put the COVID infection rate of vaccinated people at less than 1 percent, “ranging from 0.01% in Connecticut to 0.9% in Oklahoma.”

A highly cited Kaiser report similarly puts the breakthrough rate at “well below” 1 percent.

An NBC News analysis covering 38 states, meanwhile, found 125,682 breakthrough cases, which represents about 0.08 percent of the 164 million vaccinated Americans.

The actual breakthrough rate appears to be much higher than .08 percent based on anecdotal evidence, however, and a more careful perusal of state data.

Let’s start with Major League Baseball. There are about 750 professional ball players on 30 MLB teams. Applying that rate (0.08%) to MLB baseball players would mean we could expect less than one player (0.6) to experience a breakthrough case. A rate of 1 percent would mean 7 or eight players. But as previously mentioned, the New York Yankees alone had nine breakthroughs in May, and many other teams racked up breakthrough cases.

One could argue that perhaps Major League ball players, for some reason we may not yet understand, are more likely to contract the virus after being vaccinated, but plenty of other examples can be found, including the six vaccinated Texas Democrats who tested positive for COVID after taking a charter plane to Washington, DC. Ask yourself this: how many people do you personally know who contracted the virus after being vaccinated? (I know many.)

A thorough review of the evidence strongly suggests breakthrough cases are far likelier than the claims in headlines. A New York Times story published Wednesday exploring the Delta variant—which now accounts for more than half of COVID cases in the US—hinted at this.

The paper noted that the CDC “does not tally national figures on breakthrough infections that don’t result in hospitalization or death,” so the precise incidence “is unknown” even though the CDC says breakthroughs are “extremely rare.”

Seeking comment, the Times received a vague response from Walensky in reply to an email inquiring on breakthrough incidence.

“A modest percentage of people who are fully vaccinated will still get Covid-19 if they are exposed to the virus that causes it,” Dr. Walensky said in reply to a Times email.

But infectious disease experts hinted that breakthrough cases are more likely than the current data suggest. “I think that if we started to test people just randomly on the street, we would find a lot more people who test positive,” Dr. Abraar Karan, an infectious diseases fellow at Stanford, told the newspaper.

On Thursday, New York magazine published an article under the headline “Don’t Panic, But Breakthrough Cases May Be a Bigger Problem Than You’ve Been Told.”

Journalist David Wallace-Wells, who spoke to scientists at Harvard and Scripps’s, said public health officials may be “overstating the vaccine effect on transmission and understating the scale and risk of breakthrough infections.”

“The message that breakthrough cases are exceedingly rare and that you don’t have to worry about them if you’re vaccinated — that this is only an epidemic of the unvaccinated — that message is falling flat,” Harvard epidemiologist Michael Mina told Wallace-Wells.

Eric Topol, an American cardiologist and author, was more blunt, saying he estimated the vaccines’ efficacy against symptomatic transmission had fallen to roughly 60 percent for the Delta variant.

“The breakthrough problem is much more concerning than what our public officials have transmitted,” Topol said.

Wallace-Wells notes it’s impossible to estimate the true breakthrough rate because the CDC stopped tracking and reporting most breakthroughs in May, but the data he assembled paint a much different picture.

“In Delaware, between July 1 and July 22, ‘breakthrough’ cases were 13.8 percent of the total,” he writes. “In Michigan, between June 15 and July 30, the figure was 19.1 percent. In this period, there were 2,369 breakthrough cases and 12,409 in total. In Utah, 8 percent of new cases were breakthroughs in early June, but by late July, as Delta grew, the share grew, too, to 20 percent (even while the total number of cases almost doubled).”

Lies, Damned Lies, and Statistics

None of this is to say Americans shouldn’t get vaccinated. Evidence suggests it significantly reduces one’s chances of dying of or becoming hospitalized with COVID-19. A New York Times analysis of 40 states found that fully immunized people accounted for less than 6 percent of COVID deaths and less than 5 percent of hospitalizations. (Other data is even more promising, including statistics Dr. Fauci cited in June which claimed 99.2 percent of COVID deaths involved unvaccinated individuals.)

A close loved one of mine was vaccinated this week after I suggested it was a good idea; the same day, I encouraged several other loved ones to get the vaccine. This is not about being “pro-vax” or “anti-vax”; it’s about the CDC not being forthright on vaccine breakthroughs.

Choosing to not count vaccinated people who tested positive for COVID as breakthrough cases is little different than choosing to not count positive COVID cases as actual cases. Imagine how much lower US numbers would be if the CDC stopped tracking cases, and instead only counted deaths and hospitalizations.

The great American writer Mark Twain popularized a well-known saying on stats.

“There are three kinds of lies: lies, damned lies, and statistics,” Twain said. (Twain and others attributed the quote to British prime minister Benjamin Disraeli, but it’s unclear if Disraeli ever said this.)

We’ve seen throughout the pandemic how authorities have manipulated statistics to serve their own agendas—most notably New York Gov. Andrew Cuomo, who changed public health reporting to cover up the number of New Yorkers who died in nursing homes because of his policies.

By only tracking breakthrough infections that result in hospitalization and death, the CDC is depriving the public of crucial information on the efficacy of vaccines and fueling the vaccine wars. Increasingly, these wars are a bipartisan chorus of vaccinated voices who paint the unvaccinated as either crazy people—there are no microchips in it, Times columnist Charles Blow recently quipped—or filthy creatures who are prolonging the pandemic because of their selfishness.

“It’s time to start blaming the unvaccinated folks,” Alabama’s Republican Governor Kay Ivey said in July.

Ivey was echoing sentiments President Joe Biden had expressed days earlier.

“Look, the only pandemic we have is among the unvaccinated,” Biden had said while speaking to reporters on the White House lawn.

This chorus has had its desired effect. A recent Axios-Ipsos poll found that 80 percent of Americans blame the unvaccinated for rising cases—even though the US has one of the highest vaccination rates in the world—which has fueled efforts to force Americans to get vaccinated by requiring “vaccine passports” to travel or do business.

Blaming the unvaccinated for the drawn out pandemic may be popular and politically convenient, but as the Times points out, the CDC’s own data suggest that “vaccinated people can carry as much virus in their nose and throat as unvaccinated people.” Moreover, breakthrough transmissions appear to be more common than the CDC has let on—which is undoubtedly why they stopped tracking most breakthrough cases.

The Cost of Hiding the Truth

The CDC’s effort to hide breakthrough cases not involving death or hospitalization from the public eye might serve its presumed goal—getting more Americans vaccinated—but it undermines the truth and further erodes public trust in government, which is already at historic lows.

The silver lining in the story is that a full analysis of the science of vaccination makes an even stronger case that the decision of whether to vaccinate or not should be made by one person: the individual getting the vaccine.

  • Jonathan Miltimore is the Senior Creative Strategist of at the Foundation for Economic Education.