The research also forecasts around three billion infections to occur in the next two months
Institute for Health Metrics and Evaluation (IHME) forecast for global COVID-19 Omicron variant. (IHME), an independent global health research centre at the University of Washington has released a research report on Omicron, a variant of SARS-CoV-2.
Comparing the Omicron variant with the Delta variant IHME research says that the Omicron is more transmissible and with 40-60 per cent immune escape combine to lead to rapid increases in reported case counts. A much larger fraction of infections is symptomatic – likely up from 40 per cent for Delta and prior variants to 90-95 per cent for Omicron.
However, it also shared that based on the best available data, the infection-hospitalisation rate is dramatically lower (note the infection-hospitalisation rate is not the case-hospitalisation rate), likely 90-96 per cent lower than for Delta. The infection-fatality rate is dramatically lower, likely 97-99 per cent lower than for Delta.
The research also forecasts around three billion infections to occur in the next two months. That’s as many infections as was seen in the first two years of the pandemic. Peak transmission should be in mid-January with over 35 million global infections a day, nearly three times the Delta wave peak in April. Given the immune escape and transmissibility, eventually, Omicron will reach all countries soon, shares the IHME research report. Even countries with strict border controls like New Zealand based on the Delta experience are likely to eventually see Omicron surges in all country including China we expect in the future. Detected infections at the global level will reach three times previous peaks. In the US, the peak will be over 400,000 a day.
The analysis by IHME shows that increasing mask use to 80 per cent will have a huge effect on cases, hospitalizations, and deaths. More rapid and extensive delivery of third doses of vaccine will also reduce the burden of hospitalisation and death. The unvaccinated and never infected are at the greatest risk. Vaccination for the unvaccinated is a powerful way to reduce personal risk.
Given the rapid spread and increase in Omicron and the high fraction asymptomatic combined with much lower infection-hospitalisation and infection-fatality rates, employers and schools will need to re-evaluate their approach to testing and quarantine. Going forward, tracking hospitalisations rather than reported cases will be a more relevant measure for local action than case counts.
There is huge uncertainty particularly about the severity of Omicron which has a critical impact on the forecasts of hospitalisation and death. More data in the next three to four weeks may change the scenario.
