Breakthrough infections with Covid-19 are rare, less than with the flu & the vaccine still works
From Scientific American;In response to:
‘Breakthrough’ Infections Do Not Mean COVID Vaccines Are Failing
Getting flu again postinoculation is more common than a return case after a COVID shot
By Emily Willingham on August 4, 2021
Endless news cycles and viral social media warn of “breakthrough infections” in people already vaccinated for COVID-19. These reports leave the mistaken impression that protections afforded by the vaccines are not working—and they can fuel reticence among the millions of people in the U.S. who have yet to get a shot. But such infections are not only known to occur after COVID vaccination. They frequently happen following inoculation against influenza, measles and many other diseases.
SARS-CoV-2, the virus that causes COVID, is special in one way, though: more than any other pathogen, it has provided the public at large with lessons in immunology—and terms such as “breakthrough infections” and “herd immunity” have gained a broad familiarity. “It almost feels not just like a microscope but an electron microscope on every single thing that happens with the COVID vaccines,” says Kawsar Talaat, an associate professor in the department of international health at the Johns Hopkins Bloomberg School of Public Health. No vaccine is 100 percent effective, she notes, and “although some are better than others, most of them have some breakthrough infections.”
A “breakthrough” simply means that a vaccinated person has tested positive for the disease-causing agent, not that they will become ill or transmit the infection to someone else. Most vaccinated people who are infected do not have symptoms, and those that do tend to have mild illness. Even with the Delta variant of SARS-CoV-2, the vaccines show good protection against symptomatic disease and death.
Nationally, as of August 2, the U.S. Centers for Disease Control and Prevention reported that more than 164 million people have been fully vaccinated, just under half of the total population. Yet 97 percent of those who are being hospitalized for COVID-19 are unvaccinated.
The numbers underscore how reality sometimes becomes distorted in the public consciousness. “Anecdotally, from talking to my friends and family and on social media, I think people are more concerned about these breakthrough infections than their prevalence would lead you to be,” says Tara Smith, a professor of epidemiology in the College of Public Health at Kent State University.
Another worry with breakthrough cases is passing the virus to others. But people infected “tend to be less likely to transmit, no matter what we’re looking at,” Smith says. “We see this with viruses and bacteria—even with pertussis, one of the reasons that people try to ‘cocoon’ around infants” who cannot initially be vaccinated against that disease. “Cocooning” refers to vaccinating those who spend time with the infant as a protective barrier because the pertussis vaccine is not administered before the age of two months.
COVID vaccines are expected to reduce transmission among those with an asymptomatic breakthrough infection, says Nick Grassly, a professor in the department of infectious disease epidemiology at Imperial College London. “So you already have the fact that you’re immunized and less likely to become infected, and even if you are infected, your risk of transmitting the virus is reduced,” he adds. One reason is that the amount of the coronavirus, its viral load, is lower in such infections, so there is less of it to transmit.....
‘Breakthrough’ Infections Do Not Mean COVID Vaccines Are Failing
Getting flu again postinoculation is more common than a return case after a COVID shot
By Emily Willingham on August 4, 2021
Endless news cycles and viral social media warn of “breakthrough infections” in people already vaccinated for COVID-19. These reports leave the mistaken impression that protections afforded by the vaccines are not working—and they can fuel reticence among the millions of people in the U.S. who have yet to get a shot. But such infections are not only known to occur after COVID vaccination. They frequently happen following inoculation against influenza, measles and many other diseases.
SARS-CoV-2, the virus that causes COVID, is special in one way, though: more than any other pathogen, it has provided the public at large with lessons in immunology—and terms such as “breakthrough infections” and “herd immunity” have gained a broad familiarity. “It almost feels not just like a microscope but an electron microscope on every single thing that happens with the COVID vaccines,” says Kawsar Talaat, an associate professor in the department of international health at the Johns Hopkins Bloomberg School of Public Health. No vaccine is 100 percent effective, she notes, and “although some are better than others, most of them have some breakthrough infections.”
A “breakthrough” simply means that a vaccinated person has tested positive for the disease-causing agent, not that they will become ill or transmit the infection to someone else. Most vaccinated people who are infected do not have symptoms, and those that do tend to have mild illness. Even with the Delta variant of SARS-CoV-2, the vaccines show good protection against symptomatic disease and death.
Nationally, as of August 2, the U.S. Centers for Disease Control and Prevention reported that more than 164 million people have been fully vaccinated, just under half of the total population. Yet 97 percent of those who are being hospitalized for COVID-19 are unvaccinated.
The numbers underscore how reality sometimes becomes distorted in the public consciousness. “Anecdotally, from talking to my friends and family and on social media, I think people are more concerned about these breakthrough infections than their prevalence would lead you to be,” says Tara Smith, a professor of epidemiology in the College of Public Health at Kent State University.
Another worry with breakthrough cases is passing the virus to others. But people infected “tend to be less likely to transmit, no matter what we’re looking at,” Smith says. “We see this with viruses and bacteria—even with pertussis, one of the reasons that people try to ‘cocoon’ around infants” who cannot initially be vaccinated against that disease. “Cocooning” refers to vaccinating those who spend time with the infant as a protective barrier because the pertussis vaccine is not administered before the age of two months.
COVID vaccines are expected to reduce transmission among those with an asymptomatic breakthrough infection, says Nick Grassly, a professor in the department of infectious disease epidemiology at Imperial College London. “So you already have the fact that you’re immunized and less likely to become infected, and even if you are infected, your risk of transmitting the virus is reduced,” he adds. One reason is that the amount of the coronavirus, its viral load, is lower in such infections, so there is less of it to transmit.....