Thread by @Laurie_Garrett

I strongly disagree. From a public health point-of-sale view the primary purpose of a #vaccine is to prevent infection and transmission. Clinically, it may be great to block disease, too. Goes to famed Salk vs Sabin debate on polio vaccines.

https://twitter.com/ashishkjha/status/1478516153962188800

There are longstanding debates about use of the Salk (IPV) vs Sabin (oral) polio vaccine, for reasons explained well here by @profvrr :
virology.ws/2015/09/10/why…
But back in the 1960s Salk & Sabin debated which of their vaccines better blocked fecal transmission.
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With improved sanitation & clean drinking water polio spread is greatly reduced. But could both viruses cut not just disease in individuals, but also environmental contamination via feces? pubmed.ncbi.nlm.nih.gov/6262150/
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"Oral poliovirus vaccine (OPV), because it is believed to mimic natural (wild) poliovirus infection and to induce serum and mucosal immunity, is considered ideal to interrupt virus transmission in countries with poor sanitation and endemic polio." pubmed.ncbi.nlm.nih.gov/11763328/
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Here's Jonas Salk's take:
"Data are presented to illustrate the degree to which the respective risks occur in developed & developing countries. The ultimate elimination of risk by eradication of wild and vaccine virus frm the population is discussed." pubmed.ncbi.nlm.nih.gov/230106/
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Pre-vaccines, models show 99% of transmission of polio was fecal, frm asymptomatic individuals. journals.plos.org/plosbiology/ar…
And oral vaccines interrupted that: "Trivalent vaccine (OPV) successfully interrupts poliovirus
transmission by producing both serologic and intestinal - "
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" -- immunity. In industrialized countries, 3 doses of OPV result in high rates of seroconversion. Because
excretion of wild poliovirus is prevented... in immunized persons, transmission dies out in highly immunized vaccinated populations"
watermark.silverchair.com/175-Supplement…

I did not refer to "sterilizing immunity" -- rather, lowered risk of fecal transmn, cutting community spread of virus.
A clear case of sterilizing immunity is the rinderpest vax for cattle, which stops spread completely. meta.org/papers/long-te…
Rinderpest was eradicated in 2011.