South Africa illuminates our future
https://ourworldindata.org/coronavirus
South Africa, omicron situation and trends
Cases, + 26,976
Will increase for the next few weeks
Positivity, 32.2%
Deaths, + 54
Professor Shabir Madhi
Gauteng
Cases probably peaked
More transmissibility
Combined with more population prior immunity
Three to four weeks, down from 8 weeks in previous waves
Uncoupling of cases severe disease and death rate
Delta
20,000 reported cases per day resulted in with 250 to 300 deaths
Omicron
Deaths 10 times less
Omicron not less virulent
But more community immunity
Antibodies and T cells
Omicron is antibody evasive
T cytotoxic immunity is relatively well conserved
This is what is causing the uncoupling
T cells come from infection and vaccination
Gauteng, serum survey 73% have been infected by the virus, this has led to a lot of T cell immunity
Both will protect against severe disease
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https://www.discovery.co.za/corporate/news-room
Data from the first three weeks of the Omicron-driven wave in South Africa
Data, spanning clinical records, vaccination records, pathology test results
3.7 million people
Omicron: A highly transmissible variant causing rapid community spread
The Omicron variant of SARS-CoV-2
Fuelling South Africa’s fourth wave
Genomic Surveillance, Omicron over 90% of new infections
Has displaced Delta variant
The Omicron-driven fourth wave has a significantly steeper trajectory of new infections relative to prior waves.
National data show an exponential increase in both new infections and test positivity rates
Vaccine effectiveness during the current Omicron wave
SAMRC, n= 211,000 positive tests
41% from adult members who had received two doses of the Pfizer
78,000 of these COVID-19 test results were attributed to Omicron infections
To-date laboratory analysis has provided early insights into potential reduction in the effect of neutralising antibodies against the Omicron variant
Two doses of the Pfizer
Two-dose Pfizer-BioNTech vaccination provides significant protection against hospitalisation in individuals with Omicron variant infection
33% protection against infection, relative to the unvaccinated
(down from 80% protection against infection)
70% protection against hospital admission
(down from 93% with delta)
Protection against hospital admission is maintained across all ages
Protection against admission is consistent across a range of chronic illnesses
Diabetes, hypertension, hypercholesterolemia, cardiovascular diseases
Reinfection risk
Omicron reinfection risk significantly higher compared to prior variants
Overall, the risk of re-infection (following prior infection) has increased over time
Infected with Delta, a 40% relative risk of reinfection with Omicron
Infected with Beta, a 60% relative risk of reinfection with Omicron
Infected in first wave, a 73% risk of reinfection
Risk of severe disease and hospitalisation significantly lower in Omicron infection compared to prior variants
This lesser severity could, however, be confounded by the high seroprevalence levels of SARS CoV-2 antibodies in the general South African population
Risk of hospital admission among adults diagnosed with omicron is 29% lower
Hospitalised adults, lower propensity to be admitted to high-care and intensive-care units, relative to prior waves
Preliminary observations on Omicron experience in children
Under 18 have a 20% higher risk of admission when infected with Omicron
Also increase in admissions for children under five
Many are incidentally discovered in hospital
Children were 51% less likely to test positive for COVID-19 relative to adults in the Omicron period
Where children require admission for complications of COVID-19
Bronchiolitis
Pneumonia
Severe gastrointestinal symptoms and dehydration
The majority of children present with mild disease, with symptoms such as a sore throat, nasal congestion, headache and fever that resolves within three days
Source