4 ms·

https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(21)00690-3/fulltext https://www.thelancet.com/journals/laninf/article/PIIS1473-3... positive ->

https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(21)00690-3/fulltext https://www.thelancet.com/journals/laninf/article/PIIS1473-3... positive -> vax infections 1/3 less likely than positive -> unvax - seems like it did prevent (some) infection for Delta at least.

busymom0 5y ago
This study has several issues which are rightly pointed out by the author: > Owing to the small sample size, the authors were not able to establish the vaccine effectiveness against asymptomatic infections versus symptomatic infections. This limitation together with the unconfirmed source of transmission in many of these index-contact pairs, suggests that the low SAR reported here should be interpreted with caution. > this study unfortunately also highlights that the vaccine effect on reducing transmission is minimal in the context of delta variant circulation. > They report that peak viral loads showed a faster decline in vaccinated compared with unvaccinated people, although peak viral loads were similar for unvaccinated and vaccinated people. > Time since vaccination in fully vaccination contacts was longer for those infected than those uninfected, suggesting that waning of protection might have occurred over time, although teasing out general waning versus reduced vaccine effectiveness due to delta is challenging owing to so many confounding factors. The study is meaningless without disclosing how long after the vaccination is he study done. While the study does mention waning effectiveness, it doesn’t mention (as far as I can find) how long after the vaccination did they do the sampling. Other studies show that in the first 2 months, the breakthrough is less likely and viral load is less but after that, the breakthroughs become more common and by 4-6 months, the viral load becomes the same. This is observable in my province here in Canada where vast majority of the vaccinations occurred after June 10th (we had under 10% vaccination till June 10). So in the first few months of the honeymoon period, breakthroughs were less common. However after 3-4 months, they became more and more common. And now that omicron is here, it’s become wildly common. While only 77% of Ontario population is vaccinated, 80% of cases are fully vaccinated. Another thing to mention is that the study doesn’t mention the age, comirbidiies and obesity level of the individuals. It’s shown in other studies that older people, obese and those with comorbidities have higher viral loads and shed the virus for longer. And the effectiveness also wanes quicker in these groups along with in men. So there are too many variables. These shots should never have been labelled a vaccine based on these factors.
- itsdrewmiller 5y ago
  Can you link to these studies?

busymom0 5y ago

This study has several issues which are rightly pointed out by the author: > Owing to the small sample size, the authors were not able to establish the vaccine effectiveness against asymptomatic infections versus symptomatic infections. This limitation together with the unconfirmed source of transmission in many of these index-contact pairs, suggests that the low SAR reported here should be interpreted with caution. > this study unfortunately also highlights that the vaccine effect on reducing transmission is minimal in the context of delta variant circulation. > They report that peak viral loads showed a faster decline in vaccinated compared with unvaccinated people, although peak viral loads were similar for unvaccinated and vaccinated people. > Time since vaccination in fully vaccination contacts was longer for those infected than those uninfected, suggesting that waning of protection might have occurred over time, although teasing out general waning versus reduced vaccine effectiveness due to delta is challenging owing to so many confounding factors. The study is meaningless without disclosing how long after the vaccination is he study done. While the study does mention waning effectiveness, it doesn’t mention (as far as I can find) how long after the vaccination did they do the sampling. Other studies show that in the first 2 months, the breakthrough is less likely and viral load is less but after that, the breakthroughs become more common and by 4-6 months, the viral load becomes the same. This is observable in my province here in Canada where vast majority of the vaccinations occurred after June 10th (we had under 10% vaccination till June 10). So in the first few months of the honeymoon period, breakthroughs were less common. However after 3-4 months, they became more and more common. And now that omicron is here, it’s become wildly common. While only 77% of Ontario population is vaccinated, 80% of cases are fully vaccinated. Another thing to mention is that the study doesn’t mention the age, comirbidiies and obesity level of the individuals. It’s shown in other studies that older people, obese and those with comorbidities have higher viral loads and shed the virus for longer. And the effectiveness also wanes quicker in these groups along with in men. So there are too many variables. These shots should never have been labelled a vaccine based on these factors.

itsdrewmiller 5y ago
Can you link to these studies?