Scientific illiteracy has gone beyond the usual suspects like libertarian or tight-wing conspiracy theorists or social media. NY Supreme Court recently ruled that 1700 NYC employees fired over COVID-19 vaccine policy noncompliance must be reinstated with backpay: "[b]eing vaccinated does not prevent an individual from contracting or transmitting COVID-19."
For every 10,000 vaccinated patients who develop COVID only 1.5 die and only 18 wind up with severe disease, according to a U.S. National Institutes of Health review published in January and based on data from 1.2 million fully vaccinated people.
A study of essential and frontline workers in six US states who tested positive for COVID-19 and received two or three mRNA vaccine doses before Delta infections and three doses before Omicron infections suggests that they had significantly milder infections and lower viral loads than their unvaccinated peers.In earlier COVID-19 posts, I discussed the cocooning strategy: "protect infants and other vulnerable individuals from infectious diseases by vaccinating those in close contact with them. If the people most likely to transmit an infection are immune, their immunity creates a "cocoon" of protection around the newborn (or other vulnerable person)...Cocooning for pertussis has been recommended by the Centers for Disease Control and Prevention (CDC) in the United States since 2006." Newborns with developing immune systems are particularly vulnerable to infections. Immunity can be natural or acquired (via vaccine). Vaccines, short of sterilizing ones, don't guarantee against infection, and that's why you see discussions of things like viral loads (relevant to transmission0. In theory, one's immune system should reduce viral load, relevant to disease transmission. (Also note one's immune system with natural or acquired immunity should mitigate against serious infection, e.g., with milder, shorter-lived symptoms.) In the case of pertussis, cocooning can reduce cases by 20%, earlier vaccination by mothers even more.
We know that people with allergies to vaccines, impaired immune systems (including some younger people) cannot readily acquire immunity through immunization, which is part of the reason we worry about transmission of disease and seek herd immunity. Tom Woods and other skeptics point out lower, nearly statistically negligible serious disease among children and young adults; the problem is they can get infected and transmit the disease to others at risk (including older relatives), cocooning on a larger scale.
Much has been made over a Pfizer executive (Janine Small, president of international markets) admitted not tracking post-vaccine transmission.
First. let's look at some cross break stats from Minnesota, one of the states explicitly reporting on breakthrough (vaccinated) incidents:
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Now there are some complications in data collection: We don't have full testing. There is some reason to believe asymptomatic infections are underreported. Among other things, the unvaccinated may include some previously infected with natural immunity. The original approved vaccines were designed for Alpha, not Delta or Omicron, so we would expect somewhat less effectiveness, at least in comparison to recently released bivalent boosters. Second, we know there's waning antibody protection, particularly for certain risk group like age, and so some fully/primary vaccinated people have not been recently boosted.
Now I have knowledge of certain families in my extended family; this is anecdotal evidence, which means it's not relevant from a statistically valid standpoint for inferences to a general population. One of my nephews is married with a 1-year-old son. He, his wife, and his mother-in-law, a schoolteacher, were vaxxed. His mother-in-law spread it to his wife and son, all who had bad symptoms. My nephew got tested, negative/no COVID. My younger sister and her husband, in late middle age, host a grown divorced daughter/teacher and their primary school grandson. The latter two were also symptomatic breakthroughs. My vaxxed/boosted sister and brother-in-law didn't develop symptoms {they tried to get tested but couldn't find any available locally). On the other hand, my oldest nephew and niece's families (separate states; families of 6 and 5) all got infected before vaccines in 2020.
Now I haven't seen many experimental "gold standard" ransom sample designs, and some studies report inconsistent results (which may require replication and/or greater statistical power, i.e., bigger sample studies. For example, I recall one study which reported similar viral loads for vaxxed and unvaxxed infected. Several other studies report lower viral loads for vaxxed (which one would expect for antibody/T cell immune responses to infection). Not to mention most breakthrough cases tend to be asymptomatic or mildly symptomatic, with quicker recovery and less viral shedding.
The simplistic comparisons can be misleading: infections can differ by variant, recency of vaccination, prior exposure, health condition/age, and nature/extent. Also, about 75% of the population is fully-vaxxed, so raw counts of infections can be misleading. Older people also tend to have more complicated health problems, which can might attribution of cause of adverse events more complex and arbitrary.
Let's be clear: COVID-19 was the third highest cause of death in the US for 2020/2021, behind heart disease and cancer. When you see rates of death 10 times or more among unvaxxed people, easily preventable by a free up to 2-shot protocol, it's a tragedy. My oldest niece's in-laws died painfully from COVID-19 (as I recall, after vaccines were released).
But let's also focus on the idiotic claims of the anti-vaxxers and the court that vaccination doesn't really matter: vaccination doesn't stop infection or transmission. Pfizer never discounted the importance of tracking transmission, but in the short run it was focusing on effectiveness in stopping serious disease. We saw sharp reductions from vaccinations in Alpha infections and lower, but still significant in Delta and omicron infections from the original vaccine.
Much was made of some studies showing no differences in viral loads from Delta breakthrough cases. But (over and beyond elapsed time since the last primary shot, knowing antibody protection can wane after several months among certain at risk groups), as I recently pointed out in a journal post, a new pan-coronavirus vaccine requires 3 doses. In other words, the more contagious Delta variant may have required additional doses. Again, booster data show improved effectiveness.
In theory, we would expect acquired immunity to help our bodies fight off infections, which should improve recovery and lower viral shedding, virus; obviously individual differences like patient age, severity of illness, comorbidities, and immune status.play a role.
This is not a conspectus of studies on transmission from breakthrough cases (i.e., prior vaccinated). I am aware of a more rigorous study, "Prevent COVID U, a new study evaluating SARS-CoV-2 infection and transmission among college students vaccinated with the Moderna COVID-19 vaccine, mRNA-1273." This was launched a year ago last spring; I'm not aware of any study reports yet I found this Healthline post (from last year?) a more readable discussion of general salient issues.
One of my favorite newer sources is Science Based Medicine. They did a good op-ed on this "scandal" sparked by some EU anti-vaxxer that Pfizer admitted it did not submit transmission data from vaccine breakthroughs; Tucker Carlson and some Twitter users hyped the kerfuffle. Gorsi starts out with an observation I've repeatedly made that not all vaccines are sterilizing:
He cites this relevant Scientific American article:
Although many vaccines widely used today (against measles, for example) produce very effective sterilizing immunity, others, such as the hepatitis B vaccine, do not. With these vaccines, an individual’s immune system is trained to prevent illness, yet the pathogen can persist in that person’s body, potentially allowing them to infect others. A lack of sterilizing immunity means that the pathogen can continue to circulate in a population, where it may cause illness in unvaccinated and vulnerable people or evolve to evade our immune responses, Bowdish explains.
The case of rotavirus—which causes severe vomiting and watery diarrhea and is especially dangerous to infants and young children—is fairly straightforward. Vaccination limits, but does not stop, the pathogen from replicating. As such, it does not protect against mild disease. By reducing an infected person’s viral load, however, it decreases transmission, providing substantial indirect protection. According to the Centers for Disease Control, four to 10 years after the 2006 introduction of a rotavirus vaccine in the U.S., the number of positive tests for the disease fell by as much as 74 to 90 percent .
[T]he introduction of [non-sterilizing] pertussis vaccines in the 1940s cut annual U.S. cases from more than 100,000 to fewer than 10,000 by 1965. In the 1980s cases began slowly climbing again as parents increasingly refused to vaccinate their children.
The FDA specifically pointed out in approving Pfizer for emergency authorization:
At this time, data are not available to make a determination about how long the vaccine will provide protection, nor is there evidence that the vaccine prevents transmission of SARS-CoV-2 from person to person.Some "scandal"
I would recommend the interested reader to read Gorsi's post in total; he goes into detail about the 3 phases of studies for vaccine approvals, and he also points out that the mRNA vaccines have proven very effective (although somewhat reduced) .against variants not designed for
I once more ask readers to get vaccinated and get the latest bivalent booster if it's been 2 months or more since your last COVID-19 shot.
