May 10, 2021: The World Health Organization published a Scientific Brief, with the following key messages:
- Within 4 weeks following infection, 90-99% of those infected develop neutralizing antibodies
- In most people, immunity remains robust against reinfection for at least 6-8 months (that is the longest followup period so far)
- Besides targeting the spike protein, natural immunity’s cellular immunity also targets other viral proteins
- Protection is still not well understood
July 20, 2021: Cohen et al in the journal Cell Reports: Longitudinal analysis shows durable and broad immune memory after SARS-CoV-2 infection with persisting antibody responses and memory B and T cells
- Most recovered Covid-19 patients mount broad, durable immunity after infection
- Neutralizing antibodies show a bi-phasic decay with half-lives of more than 200 days
- Spike IgG+ memory B cells increase and persist post-infection
- Durable polyfunctional CD4 and CD8 T cells recognize distinct viral epitope regions.
April 20, 2021: Ivanova et al, in MedRxiv: Discrete immune response signature to SARS-CoV-2 mRNA vaccination versus infection
- There was a dramatic upregulation of interferon signaling (IFN) in the patients but not in the vaccinated subjects.
- Anti-NC antibodies wre only detectec in patients, not in vaccinated subjects.
- IgG antibody levels remained high for at least 7 weeks after the first vaccine dose, but IgA antibody titers declined steadily beginning 1 week after the second vaccine dose.
- A striking expansion of circulating plasmablasts were observed in patients, but not after vaccination.
- Plasmablasts for genes involving IL-6 receptor signaling were enriched for both.
- Infection potently induced IFN responses, not observed in the vaccinated subjects.
- Cytotoxic CD4 T cells were observed in patients but were absent in vaccinated subjects.
What happened to the “Pandemic of the Unvaccinated?”
- 246 infected, 3 dead from COVID-19 in Michigan despite being vaccinated, Bridge, April 20, 2021
- Almost 4,000 fully vaccinated people in Massachusetts have tested positive for Covid-19, Fox, June 21, 2021
- Half of Covid-19 infected adults in Israel in latest outbreak were fully vaccinated, Sharyl Attkinsson Report, June 28, 2021
- Covid-19 infects about 100 vaccinated crewmembers on HMS Queen Elizabeth, Fox, July 13, 2021
- 79 People Dead, 303 Hospitalized in Massachusetts. Breakthrough Cases, NBC, July 14, 2021
- 49 Fully Vaccinated People in New Jersey Have Died From Covid-19, The Blaze, July 21, 2021
- 31 Fully Vaccinated People Die in Tennessee, Fox, July 23, 2021
- More than 1,000 breakthrough Covid cases reported in Tennessee, News4, Jly 23, 2021
- Covid spreading fast in well-vaccinated California counties, Mercury News, July 24, 2021
- Massachuetts has now reported more than 5,000 breakthrough Covid , infections, 80 deaths, CBS Boston, July 21, 2021
- Shooting for Hollywood film shuts down after vaccinated cast get Covid, Daily Mail, July 26, 2021
- 169 dead, 644 hospitalized in Illinois breakthrough Covid cases, NBC, July 28, 2021
- QUOTE: “The state only reports breakthrough infections among those who have been hospitalized or died, following guidance from the CDC”
- CDC: 74% of Covid cases in study were among full vaccinated, Star Democrat, July 30, 2021
- Coronavirus cases spike in highly vaccinated Israel but drop in unvaccinated Palestine, Dr. Eddy Betterman, August 22, 2021:
Are vaccinated people contagious?
- CDC says fully vaccinated people spread the Delta variant and should wear masks, Insider, July 27, 2021
- Vaccinated People With Breakthrough Infections Can Spread The Delta Variant, CDC Says NPR, July 30, 2021
- The war has changed. Delta strain equally contagious in vaccinated cases, masks a must, CDC says, Newsweek, July 29, 2021
- Fauci: Amount of virus in breakthrough delta cases ‘almost identical’ to unvaccinated , The Hill, August 1, 2021
- Evidence mounts that people with breakthrough infections can spread Delta easily, National Geographic, August 13, 2021
- People infected with Indian ‘Delta’ variant have a viral load 300 TIMES higher than the original COVID-19 strain and are twice as infectious, study finds, Daily Mail, August 24, 2021
- Delta cases show 300 times higher viral load – S. Korea study, Reuters, August 24, 2021
- Note: This and the one above are referring to the same study but neither gives a link to it nor a name of researchers.