According to one, symptomatic omicrons appear to be much less protective against re-infection than re-infection with other types of earlier coronavirus infections. New study by Qatari researchers which has not yet been reviewed.
Why this matters: If you are relying on your previous coronavirus infection to prevent recurrence, don’t do it.
big picture: Preliminary studies have found that coronavirus vaccines – especially those without a booster shot – are far less effective against omicron infection than other variants, although they hold up well against severe disease.
- This study shows that the same is true for people with prior infection, emphasizing the benefits of vaccines for this population.
By numbers: The study found that prior infections were 90% effective against symptomatic re-infection for the alpha variant, 92% effective for the delta variant and only 56% for Omicron.
- The effectiveness against hospitalization and death was 69% for Alpha, 100% for Delta, and 88% for Omicron.
Bottom-line: Omicron’s remarkable ability to evade immune defenses – either from vaccines or infections – goes a long way toward explaining its explosive case evolution.