3 ms·

Protection of previous SARS-CoV-2 infection is similar to that of BNT162b2 vaccine protection: A three-month nationwide experience from Israel https://www.medrx

by mulvya 5y ago

Protection of previous SARS-CoV-2 infection is similar to that of BNT162b2 vaccine protection: A three-month nationwide experience from Israel https://www.medrxiv.org/content/10.1101/2021.04.20.21255670v1 https://www.medrxiv.org/content/10.1101/2021.04.20.21255670v... (Pfizer vaccine) SARS-CoV-2 antibody-positivity protects against reinfection for at least seven months with 95% efficacy https://www.thelancet.com/journals/eclinm/article/PIIS2589-5370(2100141-3/fulltext https://www.thelancet.com/journals/eclinm/article/PIIS2589-5...

Scoundreller 5y ago
Be careful with your second study, because they looked at those that developed/still had antibodies post-infection. Kinda like saying those that developed a good immune response developed a good immune response. But not everyone develops long-lasting antibodies and not everyone keeps those levels high. In this study, 8-30% didn't develop/lost antibody positivity (depending on which test method used): https://wwwnc.cdc.gov/eid/article/27/3/20-4543_article https://wwwnc.cdc.gov/eid/article/27/3/20-4543_article In this study, 28% of those with documented infection had their antibodies go below the level of positivity over time: https://www.cdc.gov/mmwr/volumes/69/wr/mm6947a2.htm https://www.cdc.gov/mmwr/volumes/69/wr/mm6947a2.htm
- mulvya 5y ago
  > Be careful with your second study, because they looked at those that developed/still had antibodies post-infection. Kinda like saying those that developed a good immune response developed a good immune response. True. It depends on which specific antibody you look for, and how. Here's a recent cohort study: Anti-SARS-CoV-2 Antibodies Persist for up to 13 Months and Reduce Risk of Reinfection https://www.medrxiv.org/content/10.1101/2021.05.07.21256823v3 https://www.medrxiv.org/content/10.1101/2021.05.07.21256823v... "Here, we longitudinally measured Spike (S) and Nucleocapsid (N)-specific antibodies in 1,309 healthcare workers (HCWs), including 916 COVID-19 negative HCWs and 393 convalescent COVID-19 for up to 422 days post-symptom. ... Overall, 69 SARS-CoV-2 infections developed in the COVID-19 negative group (incidence of 12.22 per 100 person-years) versus one in the COVID-19 positive group (incidence of 0.40 per 100 person-years), indicating a relative reduction in the incidence of SARS-CoV-2 reinfection of 96.7% (p<0.0001)." Of course, these antibodies <--> protection studies are a bit of streetlamp effect phenomenon. Antibodies are relatively easy to measure so that's what immune endurance studies tend to check for. The relative risk of reinfection in real-world settings is the more robust measure.

by mulvya 5y ago

Scoundreller 5y ago

Be careful with your second study, because they looked at those that developed/still had antibodies post-infection. Kinda like saying those that developed a good immune response developed a good immune response. But not everyone develops long-lasting antibodies and not everyone keeps those levels high. In this study, 8-30% didn't develop/lost antibody positivity (depending on which test method used): https://wwwnc.cdc.gov/eid/article/27/3/20-4543_article https://wwwnc.cdc.gov/eid/article/27/3/20-4543_article In this study, 28% of those with documented infection had their antibodies go below the level of positivity over time: https://www.cdc.gov/mmwr/volumes/69/wr/mm6947a2.htm https://www.cdc.gov/mmwr/volumes/69/wr/mm6947a2.htm

mulvya 5y ago
> Be careful with your second study, because they looked at those that developed/still had antibodies post-infection. Kinda like saying those that developed a good immune response developed a good immune response. True. It depends on which specific antibody you look for, and how. Here's a recent cohort study: Anti-SARS-CoV-2 Antibodies Persist for up to 13 Months and Reduce Risk of Reinfection https://www.medrxiv.org/content/10.1101/2021.05.07.21256823v3 https://www.medrxiv.org/content/10.1101/2021.05.07.21256823v... "Here, we longitudinally measured Spike (S) and Nucleocapsid (N)-specific antibodies in 1,309 healthcare workers (HCWs), including 916 COVID-19 negative HCWs and 393 convalescent COVID-19 for up to 422 days post-symptom. ... Overall, 69 SARS-CoV-2 infections developed in the COVID-19 negative group (incidence of 12.22 per 100 person-years) versus one in the COVID-19 positive group (incidence of 0.40 per 100 person-years), indicating a relative reduction in the incidence of SARS-CoV-2 reinfection of 96.7% (p<0.0001)." Of course, these antibodies <--> protection studies are a bit of streetlamp effect phenomenon. Antibodies are relatively easy to measure so that's what immune endurance studies tend to check for. The relative risk of reinfection in real-world settings is the more robust measure.