Video: https://www.tiktok.com/@distilledscience/video/7484055990875311391
Transcript
There are people who don't vaccinate, but also the vaccine itself wanes. The vaccine wanes about 4.5% per year. So that means older people are essentially unvaccinated. He's right that vaccine effectiveness does wane. But he's wrong about the number. If it were 4.5% per year, then after around 22 years, the protection would be completely gone, as he says. But we know that in populations without existing immunity, measles is one of the most contagious viruses known to man, with each person infecting around 18 other people. If all adults had no immunity, then any outbreak would spread out of control. I spent 15 hours pouring through measles studies trying to figure out where he got that number from. And the closest I could find was this paper from 1999 showing a roughly 4.25% drop in vaccine effectiveness per year. But we like to read the actual paper before jumping to conclusions. There are two main ways to measure immunity in this context. One is by looking at the amount of antibodies present in people's blood and seeing how that changes over time. The other is by looking at actual disease outbreaks, getting vaccination records, and modeling how it all spreads. This study did neither. It took a single snapshot of antibody levels in around 1,000 Canadian children. From this, they created a mathematical model that tried to fit the messy data into a prediction for how antibody levels would drop, based on the older kids having slightly lower levels than the younger kids. But they didn't do follow-up to see how the antibody levels actually dropped in a given child. And they made lots of what they called unrealistic assumptions to make the math easier, leading the authors to say that this result, is a worst-case scenario. But their whole study group received only one vaccine dose, and they got it as young as 10 months old, which matters because the younger you get the vaccine, the quicker the effects fade, because babies don't have a fully developed immune system. But now for some better data that he should have cited. One study did a 20-year follow-up on kids who were double-vaccinated. They found that after 20 years, just 5% of kids had undetectable antibody levels, and 13% were sort of on the verge. But another study did a 26-33-year follow-up with a more sensitive message. and found detectable antibody levels in all participants, with just 8% being below the level deemed to be fully protective. And of those, 4 out of 5 had received their first vaccine dose before they were 1 year old. Finally, there were two large-scale studies looking at thousands of measles cases in England and France, doing population modeling of cases and vaccination records. They both determined that the only way the data made sense was if there was a drop-off a vaccine efficacy over time. How much? exponential, leading to a vaccine efficacy of 96.7% 16 years after the second dose. And the British study found a drop off of just 0.039% per year. There's a reason why over 60 million measles deaths have been prevented by vaccination since the year 2000. So rather than downplaying their effectiveness and instead talking about things like natural immunity and vitamin A, which we'll cover next, maybe encourage people to do what decades of data have found to be safe and effective.!
Additional notes
⚠️IMPORTANT NOTES: 1. Measuring antibody levels ignores other aspects of the immune system, like B-cells and T-cells. Other studies have shown that, even once antibody levels drop below detectability or an “immunizing” level, people are often still protected from the disease because as soon as the body gets exposed to the virus their immune memory kicks back in and starts churning out new antibodies. Also, in the breakthrough cases where someone who is vaccinated does get sick, it’s generally a much milder infection. In a 2014 outbreak in the Netherlands, 106 healthcare workers (HCW) were potentially exposed. Eight developed the measles: 6 had been vaccinated twice, 1 once, 1 was unvaccinated. The 6 had a mild disease course. The once-vaccinated case had fairly severe measles, with a chest infection and mild diarrhea, but did not require hospitalization. The unvaccinated case had severe measles requiring hospitalization for pneumonia, pleurisy, oliguria, and hypotension, with abnormal findings of liver biochemical tests. NOTE 2: When measles is actively spreading, it makes sense to vaccinate children as young as possible, because mortality rates are highest in kids < 1 year old. In these cases it’s sometimes worth getting 3 total doses. But, if the rest of the population is vaccinated and measles is no longer endemic in the country, we can delay the first vaccine dose until after 15 months so as to maximize their lifetime protection. 👉 For a full writeup of this video with all the mentioned sources and many more (covering some of his other claims), sign up for my free newsletter (🔗 in bio) #science #news #measles #whofides #vaccines
References
- 1999 measles vaccine-effectiveness paper discussed in transcript; title/source URL/DOI/PMID not listed in workbook.
- 20-year follow-up, 26-33-year follow-up, England modeling study, France modeling study, and 2014 Netherlands outbreak discussed in transcript/caption; direct source details not listed in workbook.