Thread by @sailorrooscout

Early data out of SAMRC shows Omicron causes milder symptoms (with recovery within 3 days), two doses of Pfizer ARE effective against hospitalization, AND data indicates that the severity of Omicron is 29% LOWER than D614G (first) wave of COVID-19 infections in South Africa.🧵

This study looks at data from 78,000 Omicron patients in South Africa. There are 38 admissions per 1,000 Omicron cases, compared to 101 admissions per 1,000 for Delta. The proportion of hospitalized patients needing ICU is 13% for this wave compared to 30% in previous waves.

This study found that individuals vaccinated with two doses of Pfizer’s vaccine were 70% less likely to be hospitalized with Omicron compared to unvaccinated individuals. While this is LOWER than the protection vs. Delta, PLEASE KEEP IN MIND THE FOLLOWING

The lower protection (down from 93% to 70%) against hospitalization because of Omicron could be because older individuals were vaccinated first in South Africa, so there has been a longer period for vaccine-derived immunity to wane than with younger age groups!

Confounding factors for Omicron hospital admission data. High seroprevalence SARS-CoV-2 antibody levels in South Africa’s population (so antibodies due to previous COVID-19 infection) - in Gauteng = as high as 70%+ of individuals.

Regarding hospitalizations:
•Most Omicron admissions = unvaccinated individuals (16% of ICU admissions were vaccinated)
•High % of INCIDENTAL admissions (meaning being admitted to the hospital for something other than COVID and test positive upon admission).

Regarding data outside of hospital admissions:
•Early data shows milder illness with Omicron with recoveries within 3 days
•HIGHER reinfections (individuals who've had COVID get infected again) and breakthrough infections (vaccinated individuals getting infected)

Omicron cases are growing much faster than during South Africa’s Delta wave, BUT hospitalizations ARE slower. For Omicron wave, South Africa has reached 60% of cases reached during their Delta peak but they have reached only 20% of the hospital admissions of their Delta wave.

For all of this information and MORE, please read THIS thread in it’s ENTIRETY. It has everything you could want to know answered, including cases in children experiencing very low rest-positivity rates and lower admissions in absolute terms (also incidental admissions).

https://twitter.com/miamalan/status/1470684351151157252

Key Points:
•Apparent 29% LOWER severity then D614G (original virus) based on early data and supported by clinical feedback
•Vaccination remains most important intervention to mitigate against SEVERE COVID-19, two doses are still effective in reducing risk of hospitalization

•Reinfection and “breakthrough” infections likely to be higher- CAN be mitigated with BOOSTERS
•Epidemiological tracking shows steep trajectory of new COVID-19 infections indicating rapid Omicron spread, BUT with a flatter trajectory of hospital admissions ➡️ lower severity

IMPORTANT NOTE. OMICRON BEING “MILDER” IS LIKELY DUE TO IMMUNITY KICKING IN. READ THE THREAD IN IT’S ENTIRETY AND THE STUDY LINKED WITHIN.

If you are looking for a FANTASTIC booster study, look no further. Hybrid Immunity and Boosters CAN take on Omicron. This is in regards to Moderna, Pfizer, and Johnson & Johnson. Immunity can make the difference between this being “mild” SO GET PROTECTED. balazslab.partners.org/publications.h…