The Defender stated, "The study found vaccinated individuals carry 251 times the load of COVID-19 viruses in their nostrils compared to the unvaccinated," however, the paper states, "Delta variant infection cases were 251 times higher than those of cases infected with old strains detected between March-April 2020." In other words, the Delta variant is more infectious, but there doesn't appear to be any information that implies that there was a difference between viral loads in vaccinated and unvaccinated people. The only part that I could find that mentioned unvaccinated people states that another paper found no difference in viral loads between vaccinated and unvaccinated people with the Alpha variant.

Nonetheless, this paper was still informative.

In other words, vaccinated people carried 251 times more the viral load of the delta variant than those who were unvaccinated, but had natural immunity, through dealing with the old strains -- having tested positive for those older strains during March-April 2020. So, to simplify it could say: "The study found vaccinated individuals carry 251 times the load of COVID-19 viruses in their nostrils compared to the unvaccinated, who had tested positive in March-April 2020." IMO, this is more about natural immunity vs vaccinated immunity than vaccinated vs unvaccinated.

I agree. The fundamental question not addressed by the article is how the viral loads among the vaccinated infected by the Delta variant compare to the viral loads of unvaccinated also infected by the Delta variant. This is the only issue of current concern. An answer to this question would reveal whether those yet uninfected by the Delta variant are more at risk from vaccinated vs. unvaccinated people carrying this strain of the virus. It may be that the Delta strain produces higher viral loads than the original strain in whomever it infects, regardless of their vaccination status.

Back in March-April 2020 everyone was unvaccinated. So yes, it is a comparison of viral loads between vaccinated and unvaccinated.

That's not what the paper says. It states, instead, that the 251 times greater viral load is between the Delta variant patients and those who had the older variant.

No what the paper says is that the viral load of VACCINATED Delta variant patients is 251 times higher compared to the older variants...
It would be interesting to know if there is a difference in viral load with Delta patients between Vaccinated and Unvacinated..

In "March and April 2020" there were few if any vaccinated Covid19 patients in Vietnam, so this does compare viral loads between vaccinated and unvaccinated.

"HTD staff members were amongst the first people in Vietnam to be offered the Oxford-AstraZeneca COVID-19 vaccine. The first doses were given on 8th March 2021; the second doses were given in the last two weeks of April 2021."

The 251 greater viral load is in the vaccinated compared to the unvaccinated in 2020:

"For viral load comparison, we used previously reported data of SARS-CoV-2 infected cases detected in Vietnam during the early phase of the pandemic in Vietnam between March and April 2020."

That reasoning only makes sense if you assume that vaccination status is the only thing that changed that matters, i.e. that the delta variant doesn't matter. That is a pretty big leap.

no its not. It would be only the case, if they would compare delta variant with vaccinated and unvaccinated people and not two different variants. And it was already stated many times that this vaccines dont have big effect to prevent infection of delta variant, only 63%. Its like you gonna compare delta variant with vaccinated with people who are having ordinary flue which is also a different variant of a virus.

Actually, 63% is a big effect in vaccine trials, because like any control, it compounds across a population. FDA minimum requirement for the COVID vaccine was 50% as in “prevent disease or decrease its severity in at least 50 percent of people who are vaccinated.” The higher the use of a control across a population, the lower the necessary effect on an individual basis. That minimum percentage may be dependent on a number of things, including the average death rate, severity, virulence, etc.

That's not true, the study says it's healthcare workers. Healthcare workers were the first to get vaccinated, starting in late December and into January

In Vietnam, between March and April, 2020, it is highly doubtful that many people there were vaccinated.
"HTD staff members were amongst the first people in Vietnam to be offered the Oxford-AstraZeneca COVID-19 vaccine. The first doses were given on 8th March 2021; the second doses were given in the last two weeks of April 2021."

The segment "old strains detected between March-April 2020" is a reference to the older variants, such as Alpha, not the time when information about the viral loads were determined.

"Viral loads of breakthrough Delta variant infection cases were 251 times
higher than those of cases infected with old strains detected between
March-April 2020."

That says more about the virulence of Delta than it does about the overall effectiveness of the vaccines, given the fact "all recovered uneventfully," not to mention the available data on breakthrough cases where I live (Indianapolis, Indiana) point to very low breakthrough case numbers and minuscule death counts in said population, the vast majority of which are over 80.

>there doesn't appear to be any information that implies that there was a difference between viral loads in vaccinated and unvaccinated people

"Breakthrough infections" means people who get infected after being vaccinated. So you have people who were not vaccinated in 2020 compared to people who got vaccinated in 2021 and caught covid.

The entire point of the vaccine is that it stimulates the body to develop spike proteins and the body then develops antibodies to these spike proteins. The antibodies are not attacking covid directly, but just the proteins, leaving covid to replicate.

If it did attack the cells and not just the protein, then we would be teaching our bodies to attack and kill our own cells. We aren't, we are teaching them to attack the protein and leave the cells intact which leaves covid intact and free ti replicate.

Thank you for specifically mentioning "breakthrough infections". I realized that I unintentionally cut off the beginning of the line and left a response to my original comment as a correction.

First I want to say, "Sorry".

Highlighting the lines that I wanted to quote wasn't working properly so I re-typed the sentence from lines 37 and 38. When I did this, I accidentally left off the beginning of the sentence. The full sentence is "Viral loads of breakthrough Delta variant infection cases were 251 times higher than those of cases infected with old strains detected between March-April 2020." There are other sentences that are clear about this as well, such as those in lines 213-216 and lines 291-294. Also, the key words section, on line 22, has the phrase "vaccine breakthroughs."

For people who are confused about what "old strains detected between March-April 2020" means in the quote, lines 158-160 state, "For viral load comparison, we used previously reported data of SARS-CoV-2 infected cases detected in Vietnam during the early phase of the pandemic in Vietnam between March and April 2020."

In other words, the viral loads were 251 times higher in vaccinated people who contracted the Delta variant than they were for unvaccinated people who contracted previous variants of the virus. However, the quote from The Defender is still incorrect because it lumps all of the variants together.

In the abstract it speaks of the healthcare workers type of Delta strain......23 complete genome sequences were obtained.They all belonged to the Delta variant, and were phylogenetically distinct from the contemporary Delta variant sequences obtained from community transmission cases, suggestive of ongoing transmission between the workers.
Doesn't this suggest that this variant was not like the community delta variant but in the case study it seemed that the spreading and transmission was amongst the cluster of healthcare workers alone vaxed at the same time. Suggesting a breakthrough strain coming from the hospital staff alone amongst themselves... not external transmission from other sources outside the group. Their genome sequence was the same but not like the community cases.
????suggestions.
????phylogenetically distinct
????delta spread amongst vaxed

"Compared with peak viral loads of cases infected with old SARS-CoV-2 strains detected in Vietnam between March and April 2020, peak viral loads of breakthrough cases were significantly higher, median log10 viral load in copies per mL (range): 9.1 (range: 2.8–10.2) vs. 6.7 (1.9–9.5), equivalent to 251 times higher for median viral loads."

Since peak viral loads are produced during a very brief period of time, typically before the development of symptoms, we need to be sure individuals infected with the old SARS-CoV-2 strains between March & April 2020 and those infected with Delta recently were both tested at the same point in the course of their infections. And yet there's nothing in the study to demonstrate that this was the case. In fact, there's good reason to think the Delta infections were captured much earlier and thus closer to the peak viral load window: "We captured the infected cases [between 11th-25 June 2021] at a very early phase of the infection and carefully followed them up during hospitalization to assess the kinetic of viral loads and neutralizing antibodies." It's very unlikely this was done in March & April 2020. The study is simply using data collected from that period—and we don't know how early and how often those early cases were tested.

This discrepancy alone is more than enough to explain the findings here. If the cases in March-April 2020 were on average tested a day or two later in the course of their infection than the Delta cases—this is very likely if most of those early cases were detected based on symptoms—that alone would show that the Delta cases had a viral load 1000 times higher!

(Incidentally, the other recent study from China, purportedly showing that Delta cases had a viral load over 1000 times higher than the initial Wuhan strain, also had the same problem as this one.)

There is a MUCH SIMPLER EXPLANATION, you're overthinking a simple situation ... the vaccinated are simply testing higher because that's what the vaccines command their cells to do... create viral fragments by the billions everyday day after day until the vaccinated person expires and their body is incinerated.

Thanks for that insightful observation. I find that many of the study need a careful reading through as it is rarely as black and white as it is being reported.

Among the 123 cases who were unvaccinated or partially vaccinated, one was hospitalized
(0.8%) and no one died. Percentage with symptoms was not reported.
Vaccinated and unvaccinated cases were found to have very similar viral loads (in a sample of
127 and 84 cases, respectively). This means the PCR tests showed that vaccinated and
unvaccinated infected people were carrying similar amounts of virus in their upper respiratory
tracts at diagnosis and were thus equally infectious.-https://theexpose.uk/wp-con...

Can you share a reference showing that the viral load can drop rapidly in a matter of 1 to 2 days, enough to explain a 251-fold difference in viral load?

Do you have a reference you can share that tracks the time course of viral loads, particularly supporting the statement you made that 1-2 days later could explain a 1,000-fold drop-off in viral load? I find that difficult to believe and would appreciate seeing the data.

Sounds plausible.

Correction suggestions:

In Line 78: (pre)symtomatic
Should be : (pre)symptomatic

Line 385 : https://wwwcdcgov/coronavirus/2019-ncov/science/science-briefs/sars-cov-2-transmissionhtml
Should be: https://www.cdc.gov/coronav...

Line 402, Figure 2, Supplementary Notes to Figure 3 : presymtomatic
Should be : presymptomatic

Line 423 : neutralizing antibodes
Should be: neutralizing antibodies

Line 424, Figure 5 : abd
Should be: and

Table 1: Demographics and clinical characteristics of the study participants
Symptoms : Cough, n(%) - 23(37.1) 19(57.6) 14(48.3)
Should be : Cough, n(%) - 33(52.2) 19(57.6) 14(48.3)

Supplementary Notes to Figure 3: ragne
Should be: range

Supplementary Figure 4: Seroconverion AND seroconverstion
Should be: seroconversion

It's AZ in the paper. But it doesn't matter what it is +1 month out. They are all the same mRNA S1 blocking mechanism beyond that.

Typo in line 98 of pre print. Even, not event

Whath vax were these vaxxed people given? Why is this not disclosed?

It's not written in the abstract, but is written in the paper, which you can downloaded at the last link in the suggestion citation box above.

It says:
"HTD staff members were amongst the first people in Vietnam to be offered the Oxford-AstraZeneca COVID-19 vaccine. The first doses were given on 8th March 2021; the second doses were given in the last two weeks of April 2021."

In the description of keywords, I found this: "Oxford-AstraZeneca"

Line from report:

"Viral loads of breakthrough Delta variant infection cases were 251 times
higher than those of cases infected ith old strains detected between
March-April 2020." But this is being twisted by anti-vaxxers in a Facebook meme. They're claiming that it says "vaccinated people that get the Delta variant have 251 times the viral load as unvaccinated that contract Delta". It is truly disgusting to see people pass false information and even more appalling is that when I flagged this as "false information" Facebook did NOTHING.

What the study should have done is simply compare the viral loads of vaccinated and unvaccinated now, instead of having two variables: vaccinated now vs. unvaccinated in 2020 (possibly different strain).

Such studies already exist and they say that the load is similar at the beginning but it decreases rapidly in vaccinated people.

https://www.medrxiv.org/con...

Vaccines were implemented in Vietnam beginning in March 2021. Very few people were vaccinated in March of 2020. Therefore, isn't it accurate to say the viral load is higher than unvaccinated people? The infected people in March/April 2020 would have been unvaccinated. I am interested - why do you think this is inaccurate? Maybe I am missing something :-)

Delta alone gives you about 1000 times higher load than previous variants*. If some conclusion is ought to be drawn from this, is that the multiplier is lower in these breakthrough cases.

* https://virological.org/t/v...

I searched for the same. I found a study showing 'no statistical difference' to 10 times increase in Delta viral load compared 'historical', Alpha and Beta variants, only.

https://www.journalofinfect...

Very large gap between this study and the other.

The comparison was between the new Delta variant to the original Covid in 2020. There wasn't a vaccine in March-April 2020, but looking at the lower number of vaccinated people that get infected with Delta compared to the viral load in unvaccinated people with Delta does NOT state that unvaccinated have a lower viral load with Delta. The statement is that the Delta variant has a higher viral load PERIOD.

I also think that's what it's saying.

Two different viral strains! Another variable, but not taken into account.

“ March-April 2020”
Do you know who were vaccinated in March April of 2020? Nobody. They are comparing unvaccinated to vaccinated. Your narrative is not supported by facts.

But it's comparing apples to oranges then. You have to compare between unvaccinated with original strain and unvaccinated with new strain for the comparison to make sense. Here the comparison is vaccinated-new strain with unvaccinated-old strain.

Yes, it's not a very good comparison.

Translations of this are flooding Polish social medias too. Delta vs "old" variants should be stressed out more in the abstract I think.

Part of the 'false information' charge comes from an inability to tie a lot of information together. Significantly, the infected people had materially lower antibody titers than their coworkers who were not infected. That hospital had a lot of workers who didn't get infected but were vaccinated. We need to understand why some aren't as well protected. And we need to understand what viral ,load means in terms of infectability. .

Doesn't the qualifier "breakthrough" used in the report imply that the cases were among vaccinated individuals?
If so, how is it wrong to restate the fact as "vaccinated people that get Delta variant..."?

The inaccurate statement is that unvaccinated people have a lower viral load than vaccinated. The higher viral load is due to Delta, not vaccination,

maybe. May be due to the different strain. We dont know.