If immunity to SARS-CoV-2 is not permanent, it will likely enter into regular circulation
Much like pandemic influenza, many scenarios lead to SARS-CoV-2 entering into long-term circulation alongside the other human betacoronaviruses, possibly in annual, biennial, or sporadic patterns, over the next 5 years (tables S2 to S4). Short-term immunity (~40 weeks, similar to HCoV-OC43 and HCoV-HKU1) favors the establishment of annual SARS-CoV-2 outbreaks, whereas longer-term immunity (2 years) favors biennial outbreaks.
If immunity to SARS-CoV-2 is permanent, the virus could disappear for 5 or more years after causing a major outbreak
Long-term immunity consistently led to effective elimination of SARS-CoV-2 and a lower overall incidence of infection. If SARS-CoV-2 induces cross-immunity against HCoV-OC43 and HCoV-HKU1, then the incidence of all betacoronaviruses could decline and even virtually disappear. The virtual elimination of HCoV-OC43 and HCoV-HKU1 would be possible if SARS-CoV-2 induced 70% cross-immunity against them, which is the same estimated level of cross-immunity that HCoV-OC43 induces against HCoV-HKU1.
我当时说疫苗存在产能问题,一堆人来和我杠,mRNA疫苗不会有产能问题,你就是见不得别人好;我说接种这些疫苗不够,「杯水车薪」,也有一堆人来杠。——不够就是不够,存在产能问题就是有产能问题,不能说发生在英国,你们就蒙着双眼不肯承认了。
备注:之前我也解释过,之所以说他们存在产能问题,是因为他们等不了,必须马上接种,不是说产能问题会一直存在。
FDA 确认辉瑞疫苗安全有效,英国正式开打,对疫情会产生怎样的影响?目前美国疫苗的接种,他们自己用了「困难、混乱、延迟」(confusion, difficulties and delays)来形容。最乐观的估计是在4月份产能基本达标,开放给所有美国人进行接种。
不知道多少人是真的铁杆反疫苗人群(民调这玩意不可尽信),如果这个比例不够高,今年年底可能真的可以达到覆盖比例(70%-80%)。——那他们就可以宣布疫情结束或者稳定了。