Studies by Discovery Health, South Africa's largest insurer, showed that people who contracted the Delta variant faced a 40 percent risk of reinfection with Omicron.
南非最大的保险公司 Discovery Health 的研究显示,接触过德尔塔的人有40%的风险会再次感染奥密克戎。
Those people had significantly more protection against reinfection with BA. 4 or 5: 76 percent against symptomatic infection, and nearly 80 percent against all infection.
When you talk about reinfection, and you don't keep in the concept of variants, that's an entirely different ball game. That's a good reason for a mask.
But in general, if you've had COVID or gotten boosted recently, it is safe to say you probably have some protection against reinfection, and especially against severe outcomes.
The reason we're seeing more reinfections with BA. 5 is partly due to its immune evasiveness — mutations in its spike protein that help it sidestep antibodies to prior variants.
People who had the original Omicron variant, BA.1, seem to have a higher rate of reinfection with these newer Omicron subvariants, compared with those infected with previous variants.
People who had the original Omicron variant, BA. 1, seem to have a higher rate of reinfection with these newer Omicron subvariants, compared to those infected with previous variants.