“Breakthrough” infection does not mean that the COVID vaccine is failing

The endless news cycle and viral social media warn of “breakthrough infections” in people who have already been vaccinated with COVID-19. These reports leave the false impression that the protection provided by the vaccine is not working. And they can fuel silence among the millions of people in the United States who haven’t been shot yet. However, such infections are not only known to occur after COVID vaccination. They occur frequently after vaccination against influenza, measles, and many other illnesses.

SARS-CoV-2, the virus that causes COVID, is special in a sense. More than any other pathogen, it has provided the general public with lessons learned from immunology and terms such as “breakthrough infection” and “herd immunity.” Is widely known. Kawasar Talaat, an associate professor of international health at the Johns Hopkins Bloomberg School of Public Health, said: No vaccine is 100% effective, she says, and “some are better than others, but most of them have some breakthrough infections.”

A “breakthrough” is a person who has been vaccinated. Tested positive for the cause of the disease, They do not get sick or infect anyone else. Most infected vaccinated people are asymptomatic and prone to mild illness. Even with the delta variant of SARS-CoV-2, the vaccine Shows excellent protection against symptomatic illness and death..

Nationally, as of August 2, the US Centers for Disease Control and Prevention 164 million people are fully vaccinated, A little less than half of the total population.not yet 97% of people hospitalized with COVID-19 are not vaccinated..

The numbers emphasize that reality can be distorted in public consciousness. “By the way, from conversations with my friends and family and social media, I think people are more worried about these breakthrough infections than their prevalence leads you,” said the Faculty of Public Health. Says Tara Smith, a professor of epidemiology. Kent State University.

Another concern in the breakthrough case is infecting others with the virus. However, infected people “tend to be less likely to get infected, no matter what we see,” Smith says. “This is seen with viruses and bacteria. Whooping cough is one of the reasons why people try to” cocoon “around infants who are initially unvaccinated against the disease.” “Cocooning” refers to vaccination of people who spend time with their baby because the pertussis vaccine is not given two months ago.

COVID vaccine Expected to reduce infection Nick Grasley, a professor of infectious disease epidemiology at Imperial College London, says among those suffering from asymptomatic breakthrough infectious diseases. “Therefore, you have the fact that you are already immunized and unlikely to get infected. Even if you get infected, your risk of getting the virus is reduced,” he adds. One of the reasons is that in such infections, the amount of coronavirus, which is the viral load, is low, so the amount transmitted is low. It’s not clear what this pattern will look like in the Delta variant. The study of the Disease Control and Prevention Center published in late July Similar virus numbers between vaccinated and unvaccinated people.. However, in that study, researchers did not perform tests to confirm true viral load or report data on infections from vaccinated people, and were “not vaccinated.” The group included partially vaccinated people.

Vaccines are ineffective, so no breakthrough cases occur. Immunity can weaken over time, and vaccines may be less effective against certain pathogens. The measles-mumps-rubella (MMR) vaccine is one example. The defense against measles is strong, but the immunity to mumps it gives is not so strong, says Talaat.

Even the powerful measles vaccine has a breakthrough history of infection. The outbreak of one measles, primarily involving vaccinated youth, in the late 1980s resulted in the following policy changes: Two doses instead of one.. According to Talaat, the first MMR vaccination has a lifelong protective effect of about 90%, while the second vaccination covers about half of the remaining 10%. Given the highly contagious nature of measles, it is important to get the best possible coverage.

Influenza vaccines are the most associated vaccinations for breakthrough infections. “We know that influenza vaccines aren’t as effective,” Smith said, when such cases of influenza were followed as closely as the groundbreaking SARS-CoV-2 infection. “There will be more,” he said. She says the breakthrough COVID case is “just another Wednesday” compared to the cases that occur with other vaccines.

The COVID vaccine seems to be much better than the flu vaccine. So far, Shot neutralizes the COVID variant very effectively. In fact, COVID does not overcome immunity as much as the flu virus, according to Grasley. And some types of flu are just right to dodge what human ingenuity throws at them. Influenza season with very ineffective vaccines And many groundbreaking cases.

“We don’t call it’breakthrough’, but say it’s 47% effective this year,” or “60% …” about the flu, Talaat said. I have. However, although the flu vaccine is relatively ineffective, she says it is “better than nothing” and can save lives and prevent hospitalization.

Breakthrough rates can increase if the vaccinated population is small and the number of cases in the community is high. Conversely, high vaccine intake means that the vaccinated population accounts for the majority of all cases.If almost everyone is vaccinated, all cases that occur Most likely to be among immunized people.. This is a situation that occurred in Massachusetts, where 74% of people who tested positive were vaccinated in areas where about 69% of eligible residents were vaccinated.

Other factors contribute to the overestimation of patients vaccinated against breakthrough infectious diseases, such as age and health associated with weakened immune systems. In many cases, the immune level of these patients causes a blunt response to the vaccine, which may be at higher risk than young, unimmunized, unaffected people.

COVID booster shots may be required for people with a weakened or gradually weakened immune system, similar to those routinely given for whooping cough. Talaat points out a report Good response to the third COVID vaccine administration In a patient who received an organ transplant. France and Israel have already added a third dose recommended for immunocompromised recipients, and the UK is considering doing so. The CDC’s Immunization Implementation Advisory Board met on 22 July to review data related to booster shots of people with immunodeficiency and conclude: This patient population may require a third dose..

In its earnings announcement in late July, Pfizer quoted unpublished preliminary results. 23 clinical trial participants This showed increased protection against delta mutants after the third dose of the mRNA vaccine.of Prepared remarks The company said in its earnings announcement that it plans to submit the results of a third dose study to the FDA in August to obtain an emergency use authorization for boosters.

In the meantime, “I don’t know if the booster will work, but if everyone is vaccinated, 2.7 percent of people in this country with immunodeficiency“Tarat says. “And they don’t have to worry about how well or how bad their immune system works to protect them from the virus.”