Thread by @miamalan

[Thread] 1. What's happening with SA #Omicron hospital + death data?

Waasila Jassat, @nicd_sa:
"Decoupling" between cases, hospitalisations/deaths = continue.

Black: new #COVID19 cases
Grey: hospitalisations
Red: deaths

Cases higher than Wave 1-3, admissions/deaths = lower

2. #Omicron started in Gauteng + spread 2 other provinces within a week. With previous waves the spread 2 other parts of the country took much longer. So with #Omicron the peaks of provinces' hospitalisations/deaths = much closer to each other.

3. #Omicron hospital admissions in SA peaked at about 60% of the #Delta wave and deaths at about 14-15%

4. Excess deaths:
1. Top graph: excess deaths for under 60
2. Lower graph: excess deaths for 60+
3. Declines over past 2-3 weeks in excess deaths, but not yet for 60+. We're starting 2 see a plateau for 60+ (rise in cases for 60+ = later in wave, so expected 2 decline later)

5. How sick did #Omicron make people?
1. Data = Lancet preprint study
2. Median length of hospital stay:
- #Omicron: 4 days; #Delta: 6 days
3. Severe disease:
- Omicron: 31.7% of admissions; Delta: 63%
4. Deaths:
- Omicron: 9.7% of admissions, Delta: 26.4%

6. Graphs with the same data as in tweet 5, that show how sick each variant made people. Black = #Omicron data.

The % of admitted patients who required supplemental oxygen during the Omicron wave = less than half than of those who needed oxygen of the #Delta wave

7. Admissions of children:
1. Over 20 years: Lower % of admissions in this group for #Omicron (Omicron = 7.2% of cases; Delta: 12%)
2. Under 20 years: Higher % of admissions in this group for Omicron (Omicron = 8.4% of cases; Delta = 3.8%)

8. Although a larger % of younger people got admitted to hospital during #Omicron compared to other waves, they didn't fall as ill as during the other waves (so milder disease and shorter hospital stays).

9. Who got admitted to hospital with #COVID19 and who died during #Omicron?
1. 82% of admissions = unvaccinated people
2. Under 40 years (lower vaccination rates): 90-100% admissions = unvaccinated
3. 82% of deaths = unvaccinated

(vaccinations = self reported)

10. WHO evidence 4 #Omicron so far:
1. Higher % of asymptomatic infections
2. Omicron affects upper respiratory tract more than lower tract
3. Lower risk for hospitalisation
4. Increased risk of reinfection
5. Vaccine effectiveness @ hospitalisation much better than @ infection

11. Summary:
1. #Omicron cases/admissions = decreasing at slower rate than that it had increased
2. Hospitals in SA = not overwhelmed during Omicron
3. Milder disease and fewer deaths during Omicron wave
4. Most admissions + deaths = unvaccinated