Posted on 07/28/2021 8:03:10 AM PDT by SeekAndFind
Total antibody levels start to wane six weeks after complete immunisation with Pfizer and AstraZeneca vaccines, and can reduce by more than 50 per cent over 10 weeks, according to a study published in The Lancet journal.
The researchers from University College London (UCL) in the UK noted that if the antibody levels carry on dropping at this rate, there are concerns that the protective effects of the vaccines may also begin to wear off, particularly against new variants.
However, they said, how soon that might happen cannot be predicted yet.
The UCL Virus Watch study also found that antibody levels are substantially higher following two doses of the Pfizer vaccine than after two shots of the AstraZeneca preventive, known as Covishield in India.
Antibody levels were also much higher in vaccinated people than those with prior SARS-CoV-2 infection, they said.
"The levels of antibody following both doses of either the AstraZeneca or Pfizer vaccine were initially very high, which is likely to be an important part of why they are so protective against severe COVID-19," said Madhumita Shrotri from UCL Institute of Health Informatics.
"However, we found these levels dropped substantially over two to three months," Shrotri said in a statement.
The findings based on data from over 600 people aged 18 and above were consistent across all groups of people regardless of age, chronic illnesses or sex, according to the researchers.
The authors highlight that although the clinical implications of waning antibody levels are not yet clear, some decline was expected and current research shows that vaccines remain effective against severe disease.
For Pfizer, antibody levels reduced from a median of 7506 Units per millilitre (U/mL) at 2141 days, to 3320 U/mL at 70 or more days.
For the AstraZeneca vaccine, antibody levels reduced from a median of 1201 U/mL at 020 days to 190 U/mL at 70 or more days, over a five-fold reduction.
"When we are thinking about who should be prioritised for booster doses our data suggests that those vaccinated earliest, particularly with the AstraZeneca vaccine, are likely to now have the lowest antibody levels," said Professor Rob Aldridge from UCL Institute of Health Informatics.
The findings support recommendations that clinically vulnerable adults, those aged 70 years or over, and all residents of care homes for older adults should be prioritised for booster doses, the researchers said.
In addition, those who were vaccinated with the AstraZeneca vaccine are likely to have much lower antibody levels than those vaccinated with the Pfizer vaccine, they noted.
"This may also need to be considered when deciding who should be prioritised when boosters are rolled out," Aldridge said in the statement.
The team acknowledged certain limitations in the data, including a small sample size for some groups.
The researchers noted that each individual only contributed one sample, so they cannot yet confirm how quickly antibody levels drop for each individual, or whether these would continue to drop or reach a stable level over the next few months.
They also noted that different people will have different levels of immunity depending on the virus neutralising ability of their antibodies as well as their T-cell responses.
"Even when measurable antibody levels are low, there is likely to be continuing immune memory that could offer long-term protection," the authors of the study noted.
They said further research will be important to establish if there is an antibody level threshold needed for protection against severe disease.
Must keep that cash flowing
not even the right IgA antibodies,
but the money and fear and Communism must flow.
Natural immunity lasts 17+ years, which is why I prefer natural immunity
You also achieve “actual immunity” after your dead!
Medical studies in general have no credibility. for enough $ you too can get a “study” that meets your specification.
RE: Natural immunity lasts 17+ years, which is why I prefer natural immunity
We are in a bind here. To acquire natural immunity, you have to RISK exposure or infection to SARS-Cov-2 and risk being severely sick. You’ll be lucky if you don’t show any symptoms or the symptoms are mild.
I agree that 99.7% of people who catch the virus recover and acquire natural immunity.
But how do you know you won’t be part of the 0.3% mortality?
It’s a risk you have to take.
Gotta get your booster every 60 days now, you pro-Covid “vaccine” Freepers!
i’ve taken much bigger...
But we know there are therapeutics to help lessen the severity and at this point, it’s pretty safe to say they’re just as effective as the vaxxes, if not more so. Those “rare” breakthrough cases, some with deaths, are well into the tens of thousands.
J&J? Moderna? Natural immunity levels? (Which I note I’m seeing almost zero studies on)
RE: Have you never survived a 99.8% survivable virus before?
Please forgive me for butting in on your exchange but I feel this is important.
I’m seeing survivability numbers being thrown about. But I am not going to quibble whether it is 99.7% or 99.8%.
I believe the AGE and HEALTH status of those infected SKEW the mortality rates for this virus.
Basicslly, the case fatality rate grows exponentially by age bucket.
Yes, I'm well aware of the data limitations, the comorbidities in the death data, and uneven accuracy in PCR tests.
But the trend seems legit. If you're 65+ you have a higher than average CFR. Below 65, especially under 30, not so much.
Re: immunity, this bug is like influenza where natural immunity may only last for limited time. People get the flu year after year. Of course, for this thing, immunity may last for 17 years. We. Don't. Know.
Getting a shot is a personal matter. Getting a messenger RNA shot isn't like a tetanus shot. I can totally understand why some people see the data and get the shots, and others see the same data and think fraud etc. and NFW. Your mileage may vary.
Yes! Merck is supposedly conducting a trial on a therapeutic as we speak! You know the one called molnupiravir. This little project set our fed govt back 1.7 B to develop.
Funny, their course of treatment for this experimental therapy is every 12 hours for 5 days. The duration of administration for their research protocol is somewhat similar to what the good clinicians at FLCCC.net are recommending for Ivermectin for the early outpatient protocol.
RE: Merck is supposedly conducting a trial on a therapeutic as we speak! You know the one called molnupiravir.
The irony is Merck was the original manufacturer of Ivermectin, the patent license of which expired decades ago. It’s no surprise that Merck does not encourage the use of Ivermectin for Covid.
Some people actually suspect that Molnupiravir is an updated version of Ivermectin ( don’t quote me, I’m just presenting what I’ve read ).
Yes, the irony in this is so rich.
The funny thing. IVM has been admin @ 4 billion times over the past 40 years. This company is rushing this new molecule to market with no safety data. I read somewhere else there were potential mutagenic risks to this new one.
Big Pharma sucks!!!
I got it before the vaccines. No choice in the matter. Even if I did, I would not take these gene therapy drugs. I don’t trust a damn thing that has government propaganda pushing it 24/7 with conflicting info every three days.
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