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BREAKING NEWS
Source: COVID-19 Booster Shots  Jan 04, 2022  19 days ago
BREAKING! Booster Efficacy Questioned! Helsinki Study Shows Only Minimal nAb Titers Against Omicron Among The Elderly Following Booster Shot!
BREAKING! Booster Efficacy Questioned! Helsinki Study Shows Only Minimal nAb Titers Against Omicron Among The Elderly Following Booster Shot!
Source: COVID-19 Booster Shots  Jan 04, 2022  19 days ago
COVID-19 Booster Shots: Worrisome findings were discovered in a new study by researchers from the Finnish Institute for Health and Welfare, Helsinki, Finland in which it was found that among the elderly, the antibody concentrations measured a month after a booster dose was low. Furthermore, not all of the elderly study participants had NAbs against the Beta and Omicron variants!


 
It should be noted that many researchers have ways of manipulating data to try to forward their agendas or the agendas of those that they are being paid by. It is also important for lay people to note that when we talk about antibodies or antibodies titers, they are tons of antibodies that are produced by the immune system as a result of exposure to a pathogen but how many of these are truly relevant to the specific pathogen and how many of these can actually neutralize the concerned pathogen effectively is another question.

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The recent emergence of SARS-CoV-2 B.1.1.529 variant that is also known as the Omicron variant with major spike protein mutations has raised concern over potential neutralization escape and breakthrough infections among vaccinated and previously SARS-CoV-2 infected subjects.
 
The COVID-19 Booster Shots study team measured cross-protective antibodies against variants in health care workers (HCW, n=20) and nursing home residents (n=9) from samples collected 1-2 months following the booster (3rd) dose.
 
The team also assessed the antibody responses in prior to Omicron era infected subjects (n=38) with subsequent administration of a single mRNA vaccine dose.
 
Following booster vaccination HCWs had high IgG antibody concentrations to the spike protein and neutralizing antibodies (NAb) were detectable against all variants. IgG concentrations among the elderly remained lower, and some lacked NAbs against the Beta and Omicron variants. NAb titers were significantly reduced against Delta, Beta and Omicron compared to wild-type virus regardless of age.
 
Vaccination induced high IgG concentrations and variable titers of cross-reactive NAbs in previously infected subjects, whereas NAb titers against Omicron were barely detectable 1-month post-infection.
 
High IgG concentrations with cross-protective neutralizing activity were detected after three COVID-19 vaccine doses in HCWs.
 
Worryingly however, the study findings showed lower NAb titers in the frail and elderly suggesting inadequate protection against Omicron breakthrough infections. However, protection against severe COVID-19 is expected but needs to be verified by further studies.
 
The study findings were p ublished on a preprint server and are currently being peer reviewed. https://www.medrxiv.org/content/10.1101/2021.12.22.21268273v1
 
The Finish study team measured titers of cross-protective neutralizing antibodies (NAbs) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in health care workers (HCWs) and nursing home residents after they had received a third booster dose of the coronavirus disease 2019 (COVID-19) vaccine.
 
The study team also assessed in detail the NAb titers of individuals infected with SARS-CoV-2 before the emergence of the Omicron variant of concern (VOC) in individuals who were vaccinated with a single messenger ribonucleic acid (mRNA) vaccine dose.
 
Despite the fact that absolute NAb titer threshold is not an established correlate, this value is highly predictive of protection against SARS-CoV-2 infection and COVID-19.
 
So far it is known as according to data supplied by previous studies, the COVID-19 mRNA vaccines were up to 95% effective against wild-type (WT) SARS-CoV-2 infection after the second dose, even among the elderly. However, follow-up data from vaccine effectiveness (VE) studies have shown waning of VE levels to 20% after five months of the second dose. For Omicron-induced COVID-19, VE estimates have shown rapid waning of immunity after two vaccine doses, which were claimed to be restored after a booster dose.
 
The study which was actually an observational clinical vaccine study included 20 HCWs and nine elderly patients in residential care homes.
 
All research participants had received the first and second dose of the Comirnaty vaccine at a median of 21 days. The booster dose of either Comirnaty or Spikevax had been given at a median of 245 days following the second dose. Following the booster dose, blood samples were collected at a median of 40 days.
 
The study team measured NAb titers against a WT SARS-CoV-2 strain, as well as the Beta (B.1.351), Delta (B.1.617.2), and Omicron (B.1.1.529) variants in HCWs and elderly subjects who received a booster vaccination six to nine months after the second dose.
 
The NAb responses against the Alpha, Beta, Delta and Omicron variants to a single vaccination were also measured in 38 subjects infected before the Omicron variant was detected.
 
These NAb responses were compared to their NAb titers to the peaking antibody response one month after reinfection.
 
The study findings showed that the anti-spike (S) immunoglobulin G (IgG) geometric mean concentrations (GMCs) 21 to 42 days following a Comirnaty booster dose increased by 1.4-fold against the receptor-binding domain (RBD) and 1.8-fold against the full-length spike glycoprotein (SFL) in HCWs as compared to the elderly.

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The IgG GMCs remained equally high in HCWs at 43 to 77 days after the booster, including against the Omicron variant.
 
Among the elderly however, the antibody concentrations measured a month after the booster dose was low. Furthermore, not all of the elderly study participants had NAbs against the Beta and Omicron variants.
 
The study findings showed that vaccination-induced antibody responses were highest in younger HCWs and lowest in individuals over 65 years.
 
Also, it was seen that, NAb concentrations declined faster with increasing age, thus suggesting that protection against breakthrough infections following a booster dose may be incomplete and short-lived in the elderly.
 
Importantly as well, the study findings also suggest that booster vaccination is most likely dose-dependent. Hence the currently licensed Spikevax booster dose of 50 μg showed a marked increase in NAb titers against Omicron in HCWs previously immunized with two doses of the Spikevax vaccine.
 
It was also found that the HCWs who received a full dose of a Spikevax booster had 2.2-fold (RBD) to 2.5-fold (SFL) greater IgG GMCs as compared to those vaccinated with Comirnaty.
 
Significantly in HCWs vaccinated with two doses of an mRNA vaccine, Spikevax induced two-fold greater antibody concentrations compared to Comirnaty. However, 20% and 24% of the subjects vaccinated with Comirnaty had NAbs against the two Omicron variants tested as compared to 100% against the Beta and the Delta variants.
 
It should be noted that the kinetics of antibody responses and the extent of cross-protective immunity following infection and vaccination may vary qualitatively. To this end, it was observed that anti-S IgG concentrations among previously infected and once-vaccinated HCWs were high and NAb titers variable as compared to the antibody concentrations following a third vaccine dose.
 
The study also showed that in vaccinated HCWs, a booster dose induced a memory B-cell response. In addition, in previously infected HCWs, a single mRNA vaccine dose induced higher NAb concentrations and higher antibody affinity by recalling pre-existing memory B-cells that showed rapid affinity maturation, which correlated with improved NAb titers against multiple SARS-CoV-2 variants.
 
Importantly however, as the level of NAbs declined over time, especially against antigenically different strains such as the Omicron variant, the third booster dose increased the concentration of antibodies. In addition, it improved the quality of the B cell response. As a result, this additional dose increased the potential long-term immunity against severe COVID-19.
 
The study findings support previous findings that suggest booster vaccinations raise IgG concentrations against SARS-CoV-2. However, NAb titers remained low against the Omicron variant as compared to the WT and Delta strains of SARS-CoV-2.
 
The study findings also demonstrated measurable NAbs against the SARS-CoV-2 Delta, Beta, and Omicron variants up to 2.5 months after the third vaccine dose in younger subjects.
 
In contrast, some elderly subjects did not have antibodies against the Beta and Omicron variants, even one month after the third dose.
 
It should also be noted that insignificant and barely detectable NAb titers against Omicron one month post mild SARS-CoV-2 infection caused by WT, Alpha, or Beta strains suggested an increased risk of Omicron-induced reinfection.
 
However, a single mRNA COVID-19 vaccine dose in previously infected individuals induced NAb titers comparable to the third dose of mRNA COVID-19 vaccination.
 
The study findings indicate that booster vaccinations improved protection at least temporarily, which might have helped in reducing SARS-CoV-2 transmission during the pandemic. Furthermore, booster vaccination-induced long-lasting memory B-cells and T-cell-mediated immunity against severe COVID-19.
 
However, in the case of the frail and elderly, even with booster shots, additional precautions should be taken to prevent them from getting infected by the Omicron or even any other variant.
 
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