How do vaccinated people spread Delta? What the science says
nature.com
nature.com
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7733922/
> The mucosal immune system is the largest component of the entire immune system, having evolved to provide protection at the main sites of infectious threat: the mucosae. As SARS-CoV-2 initially infects the upper respiratory tract, its first interactions with the immune system must occur predominantly at the respiratory mucosal surfaces, during both inductive and effector phases of the response. However, almost all studies of the immune response in COVID-19 have focused exclusively on serum antibodies and systemic cell-mediated immunity including innate responses.
That's why vaccinated people can still get infected (upper respiratory tract) and have no symptoms (serum antibodies). They can infect others (upper respiratory tract) when they are infected but don't have symptoms or a temperature check saying they should stay at home. Hence the CDC now recommends tests for vaccinated people who are exposed to Covid.
It was stated by Fauci and others in 2020 that current Covid vaccines are non-sterilizing. There are new Covid vaccines in development which provide sterilizing immunity, delivered via nasal inhaler instead of deltoid arm muscle. The MMR (measles, mumps, rubella) vaccine is sterilizing, i.e. prevents infection and transmission.
Does this mean that Covid passports actually help spread Covid from vaccinated to non-vaccinated people who mix together without masks?
Not crazy about the wording of that sentence; it reads, to me at least, that the vaccinated kind of "duped" the un-vaccinated into thinking intermingling was safe. It removes the agency from the un-vaccinated, as if remaining both un-vaccinated[1] and mitigation of possible exposure is beyond their control.
(Nobody asked me but...) I would have worded it more like: "Does this mean that the un-vaccinated, hoping to parlay herd immunity into abdication of personal and societal responsibility, ended up playing themselves?"[2]
[1] I'm separating the legit medically immuno-compromised from voluntarily un-vaxxed.
[2] I'm in Texas and was fully vaccinated as early as possible with two kids that can't be vaccinated yet and am currently watching a surge drown our local hospitals so I'm super fucking jaded.
https://www.webmd.com/lung/news/20210729/cdc-reverses-guidan...
> Even if they’re not showing symptoms, fully vaccinated people should “get tested 3-5 days after exposure to someone with suspected or confirmed COVID-19 and wear a mask in public indoor settings for 14 days after exposure or until they receive a negative test result,” the agency’s website says. The CDC previously said fully vaccinated people didn’t need testing after exposure unless they showed symptoms. “Our updated guidance recommends vaccinated people get tested upon exposure regardless of symptoms,” CDC Director Rochelle Walensky, MD, told The New York Times in an email. “Testing is widely available.”
Stanford University will test all students, including those who are vaccinated, https://twitter.com/stanforddaily/status/1425554996683149313
A subset of all populations globally, especially in young people, have already recovered from a Covid variant and have some natural immunity, which is sterilizing immunity (both upper respiratory system--since that is how they got naturally infected--and serum antibodies + T-cells). Governments have the option of performing national sero-surveys to statistically estimate the percentage who are already immune without a vaccine. Individuals who can afford to pay for testing can determine if they have natural immunity, including the newest FDA-EUA test for T-cells (costs $210 with blood draw, only in US for now), https://t-detect.com
That's a national policy thing; in Ireland, for instance, you can use the covid pass to go to a pub or restaurant, but if you're in an indoors public space you are still required to wear a mask. Same in France and Germany AIUI.
> There are new Covid vaccines in development which provide sterilizing immunity...
How far along are those and how long before they hit the shelf? I am guessing these can be self-administered?
https://www.telegraph.co.uk/global-health/science-and-diseas...
https://www.statnews.com/2021/08/10/covid-intranasal-vaccine...
In theory, a vaccine delivered via inhaler requires little or no training for administration, so the supply chain would be simplified. Given the current focus on vaccine passports, governments will probably want an approved witness to the vaccine being administered, even if they could technically be self-administered.
Since the vaccines cause fewer people to be infected, the unconditional viral load is lower.
https://www.ruv.is/frett/2021/08/12/janssen-group-most-at-ri...
https://www.ruv.is/frett/2021/08/12/people-told-vaccinate-to...
> “Diagnosis of infection is three-times more likely in the non-vaccinated than the vaccinated, the likelihood of hospital admission is some four-times higher, and the frequency of intensive care is five times more common in the non-vaccinated than the vaccinated. So, we are seeing that vaccination is protecting against infection and especially against serious illness, which should be a spur to everyone to get vaccinated who has not been vaccinated so far,” Þórólfur said.
Anecdotally having had COVID before isn’t necessarily protection either. I’ve a relative who has now had both one of the original strains and the Delta variant.
Is anyone doing regular tests on large groups of people to measure the rate of asymptomatic infections?
Iceland has been as well you can see the breakdown on where infections came from here: https://www.covid.is/data
According to the second link, 255k people have been vaccinated in Iceland, out of a population of 364k (according to Wikipedia). So about 70% of the population has been vaccinated.
And according to the chart "Number of vaccinated individuals among domestic infections", about 60% of infections are among fully vaccinated people.
That suggests vaccination may not reduce the chance of infection much. As does the recent spike (the largest to date) in the "14-day incidence per 100 000 inhabitants" despite 70% vaccination.
Vaccination is still worthwhile, of course, to protect against severe illness, but if neither vaccination nor previous illness will prevent infection, it seems like COVID is going to be an illness we'll experience many times in our lives (hopefully with less impact once our immune systems adapt).
I quoted the Chief Epidemiologist’s most recent statement on the facts of the matter in Iceland in the comment you initially replied to but will do so again:
> “Diagnosis of infection is three-times more likely in the non-vaccinated than the vaccinated, the likelihood of hospital admission is some four-times higher, and the frequency of intensive care is five times more common in the non-vaccinated than the vaccinated. So, we are seeing that vaccination is protecting against infection and especially against serious illness, which should be a spur to everyone to get vaccinated who has not been vaccinated so far,” Þórólfur said.”
Literally out of the mouth of the people gathering and using these statistics.
That fact alone doesn't bode well for the hope of vaccination reducing the number of COVID infections.
Regarding the comparison between vaccination rates and infection rates: if the rates of infection are equal among children and adults, and vaccination doesn't affect the chance of infection, we'd expect about 30% of the cases to be among unvaccinated children, which isn't far from the current number. Unfortunately that page doesn't break down current infections by age, but that should be considered.
> “Diagnosis of infection is three-times more likely in the non-vaccinated than the vaccinated, the likelihood of hospital admission is some four-times higher, and the frequency of intensive care is five times more common in the non-vaccinated than the vaccinated. So, we are seeing that vaccination is protecting against infection and especially against serious illness, which should be a spur to everyone to get vaccinated who has not been vaccinated so far,” Þórólfur said.
If you read further down in the statistics data there is a breakdown by population age. You need to take into account the COVID is less infectious for the young. Iceland is also going to expand vaccination for the 12-16 age group and give people who got the less effective vaccine a booster. Not coincidentally the population with the largest set of infections mixes the most and got the Jannsen vaccine, those 20-30.
That makes sense. I think it's clear that vaccination makes the infection less severe and reduces hospitalization rates. But there's also a hope, which is the basis for a lot of policy decisions, that vaccination will reduce the chance of being infected, perhaps even eliminate the illness, and Iceland's data doesn't support that.
> If you read further down in the statistics data there is a breakdown by population age.
Only for isolation and for cumulative cases, not for current cases.
> You need to take into account the COVID is less infectious for the young.
Source please. I haven't heard that before; though it is less severe for the young.
You do you but that isn’t actually correct.
In fact, the article also quotes one of the authors as saying:
"The bottom line is, this can happen — it can be true that vaccinated people can spread the virus. But we do not yet know what their relative role in overall community spread is."
https://www.cnbc.com/2021/07/23/delta-variant-pfizer-covid-v...
That 39% number (protection against symptoms) wasn't checked at the trials, or at least wasn't reported. In that same article, they state that protection against being hospitalized/ICUed is still around 90%, which are the same values we heard before. Guess that doesn't sell clicks.
Saying that delta diminishes the effectivity from over 90% to 39% is spreading misinformation. Implying it, as the above linked article does, is spreading misinformation, knowing that lots of people doesn't read beyond the headline. Vaccines are still more than 90% effective against delta variant, or any other variant so far.
The 39% above only means that vaccinated people has "only" that protection against being infected (that is, being positive on a PCR test). Even if you are asymtomatic you are counted as infected, thus the vaccine alegedly didn't protect you. But vaccinated people still has around 90% protection against being hospitalized, even in delta variant environments.
The only conclusion we can get is: herd immunity is still far. Get vaxxed ASAP, because this thing will keep spreading.
Incorrect the vaccine trials only tested for symptomatic COVID not asymptomatic, so your assertion here is wrong. The 39% number is for symptomatic COVID only.
Also if you read my original comment you’ll see I only refer to symptomatic COVID and not to death or hospitalizations, perhaps you should read more closely before blindly accusing me of being misleading.
I mean, we all knew some vaccinated people would still get Covid, about 10% of them, so do we know that there is a higher number of breakthrough cases than even that?
J&J was tested in populations that didn't have the SA variant, and Pfizer was tested in populations that did (in addition to the other combinations you mentioned). Tests were done worldwide and we had natural experiments due to different tests in different time in different (relatively) isolated populations.
That effect exists, but only covers a small percentage of the difference in efficacy.
* this is a joke reflecting how’s the childhood game of telephone can be easily translated to “consensus says”
If the vaccine provided you with strong protection against infection, you'd expect the numbers to be highly skewed towards the unvaccinated.
Second, even if it were true, the proportion of vaccinated people among the highly susceptible older population is far higher. These older people have higher chance and severity of breakthrough infection, so comparing raw number will get you misleading results.
I'm talking about those with confirmed Covid infections. It looks like the vaccination does lower the risk of infection, but it's relatively marginal. But yes, it strongly protects against serious disease.
Which seems in line with I had speculated about earlier[1].
Here's a graph from one such study that backs your claim
The vast majority of vaccinated people who get sick, do not get sick enough to go to the hospital.
I say get back to normal and let the unvaccinated adults suffer the consequences of their own actions.
For example this rather early analysis from 2020 included more than 2,000 children who got infected. 10.6% of infants under 1 year of age had severe or critical symptoms. All of these infants survived but a small number of infants in the United States have died following diagnosis with COVID-19 even then before Delta (or even Lambda and other variants).
https://pediatrics.aappublications.org/content/pediatrics/ea...
I have rolled too many d10 not to worry a lot about this.
Apart from more severe outcomes for babies than what we thought there are children that increasingly have to be treated for pneumonia at hospitals. Also long covid is on the rise. This has been widely reported recently.
https://www.nationalgeographic.com/science/article/long-covi...
https://www.google.com/amp/s/www.nytimes.com/2021/08/09/heal...
Why they are doing in person school and fighting over mask mandates I'll never understand. Even if children suffered no ill effects, they'll act as disease vectors for adults and breakthrough cases.
So I just looked into it. I found a couple of news articles [0][1]. [2] says:
> Kids remain, as they have been throughout the pandemic, at much lower risk of getting seriously sick with the coronavirus, especially compared with unvaccinated adults. But the recent rash of illnesses among the nation’s youngest is a sobering reminder of the COVID-19 adage that lower risk is not no risk. With so many children unable to access vaccines and their health contingent on those around them, parents and guardians must now navigate the reality that Delta represents a more serious danger to everyone—which means it’s a more serious danger to kids as well.
0: https://www.theguardian.com/australia-news/2021/jul/04/delta...
1: https://www.abc.net.au/news/2021-07-06/children-need-covid-p...
one source: https://www.theatlantic.com/health/archive/2021/08/delta-var...
The NYT says 1% of infected kids ends up in the hospital: https://www.nytimes.com/2021/08/09/health/coronavirus-childr... (Obviously, you need to recognize more kids are catching delta so the base is increasing.)
France tells us about kids facing long covid: https://www.france24.com/en/health/20210812-young-people-hit...
And studies indicate vaccinated ppl may stay infectious a shorter timespan.
Also, the I-MASK+ early outpatient protocol mentions using a nasal & oral rinse: https://covid19criticalcare.com/wp-content/uploads/2020/11/F...
0 - https://chrismasterjohnphd.com/covid-19/povidone-iodine-kill...
edit: less sketchy link to a study of Iota-Carrageenan nasal spray for covid prophylaxis: https://www.medrxiv.org/content/10.1101/2021.04.13.21255409v... not peer reviewed, but a registered clinical trial reporting positive results.
Is there any indication that any sort of nasal irrigation is effective at all?
If you decide to do this with tap water, leave it out for a day or so to let the chlorine evaporate and then boil it for at least 5 minutes. Netti pots are also basically waterboarding fyi. Have fun!
That said, if the virus spreaded the same with the vaccine, the advantaged would be that the virus wouldn't have as much evolutionary pressure to change and become resistant. For example, it could make it harder for lambda variant, which might be symptomatic, to become prevalent
Which is significant.
Also, most of these polices were created based on research prior to Delta becoming prevalent which showed that the vaccines indeed did reduce spread. Since Delta is more transmissible, this benefit is reduced.
So it doesn't have an impact except for when it does?
Although the vaccine seems to somewhat lessen the chance of transmission, it IMO is not enough to stomp on people's freedom. I would maybe consider it if it was the black plague.