Thread by @mlipsitch

This thread by @AlexBerenson distorts my work in a way that can only be willful, given that others have made the same arguments in the past on twitter and I have clearly refuted them. threadreaderapp.com/thread/1318176…

He takes a commentary I wrote with @ted_h_cohen about Listeria -- a bacterial disease we get typically from food -- that suggested (citing another paper -- this was not original research) that a lack of herd immunity to listeria could be leading to increased case numbers.

(of symptomatic Listeria infection). It also mentioned the idea that rubella vaccines used in the wrong way could increase severe (congenital) rubella through modest amounts of herd immunity that delay but do not prevent infection, increasing its incidence in pregnant women.

And it gave some other examples of how herd immunity could be counterintuitive. It notably talked about diseases that had been long-established in the community, and how failing to understand herd immunity (from natural infection or vaccines) could produce unintended effects.

The commentary was not for or against herd immunity, any more than one can be for or against rocks. Herd immunity is. It can (for some infections) be generated by natural infection. It can (for some infections) be generated by vaccines.

All else equal, it's better to generate herd immunity by vaccines because infections are dangerous (some are deadly) and approved vaccines are safe. Playing "gotcha" from finding discussions of herd immunity's benefits by epidemiologists reveals complete lack of understanding.

Of course we think it has benefits. Now, for COVID-19 there is a consensus of every reputable medical and public health organization that getting to herd immunity through natural infection a) may be impossible and b) if possible is worse than the alternative

It may be impossible to get herd immunity through natural infection because coronavirus immunity is typically short lived and partial, and there are signs of the same for SARS-CoV-2, though evidence is still very limited.

Getting there through natural infection is worse than delaying and -- if things go well -- getting it through a vaccine. Why? because people die from the infection, lots of them and not only those we can predict. And because we can't shield effectively even those we can predict

It's very simple. Science is about using concepts and data thoughtfully to infer how particular things will work in the world. Ideology is about finding some word or concept and unthinkingly applying it the same way each time. Herd immunity is, and it can be a mix of good & bad

Bacteria that we get from food and have been with us for centuries are different from viruses that just emerged this year. You can play games saying "gotcha" -- you said herd immunity was good in the past. Or you can do science and even responsible reporting.

Here as elsewhere @AlexBerenson chose gameplaying.