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what is herd immunity?

What is herd immunity?
A lot of old fights continue long after they should in science, if science were this instrument that the positivists extol. We are seeing one now, which is all about epidemiology and “herd immunity”.
It is worth noticing that the groups attacking epidemiology are using the same instruments that were honed in the fifties. In 1951, Doll and Hill, in Britain, published a famous epidemiology paper linking cigarette smoking to cancer. This was the first of a flood of studies linking the two. The cigarette companies, under the guidance of certain genius advertisers, found many a compliant scientist to batter against the whole idea of using the statistical models employed by Doll and Hill. These people made one of the most significant discoveries of the 20th century: in the interest of ideology and profit, you can legally obfuscate mass murder and get away with it. Thus, as cancers connected to smoking regularly swept away half a million peeps per year all through the late sixties, seventies, eighties, government did nothing but put warnings on cigarette packs. While Cold War scholars regularly brought up Lysenko to show how ideology crazily led to terror in Stalin’s Russia, they simply ignored these figures and this social phenomenon.
Their heirs have made it impossible for the world’s second largest economy, the U.S., to do the least thing towards averting the climate catastrophe we know is coming. And they are the same peeps who are behind the “let’s open the economy” crowd. Having those cancer deaths under their belt, the Corona-virus deaths will be as nothing.
One of the weapons that they bring to this battle is an unexamined notion called “herd immunity.” From the halls of George Mason University to the streets of Stockholm, this “mathematical model” is supposed to show that lockdowns are poopy ways of dealing with a minor problem.
So, what is herd immunity? A simple definition is that it is the resistance of a population to the invasion and spread of an infection. We should contextualize this definition – it arose from considerations of the level of vaccination needed to suppress an infection. Thus, for instance, they vaccinate against the hoof and mouth disease among cattle trying to firewall that disease so it does not have relays to get into the unvaccinated part of the population. There are new cows being born all the time, so there is, de facto, a new unvaccinated population coming into the picture. And the disease itself is evolving in relation to the vaccine, so that if enough of the population is not vaccinated it is possible that the evolution of the microbe will lead to resistance that overwhelms the vaccine.
Notice that all of these situations depend upon a vaccine. They also depend on the situations of the population, which can be determined by many factors. Among humans, sanitation and nutrition are pretty strong factors in the spread or suppression of infection. The percentage of the vaccinated in terms of the suppression of a disease can vary. For polio, for instance, Jonas Salk thought that an 85 percent level was needed. In practice, 70 percent was achieved in most countries, and even then there were occasional outbreaks. Still, by 2016, one of the most common oral poliovirus medicines was withdrawn, because it was no longer considered necessary. Still, other polio vaccines are in place and have been implemented in mass.
Compare this regime to the regime of having no drug to cure the disease. In this case, herd immunity means something like: the herd will be culled so that the resisters will survive. Or as George Scott said in Dr. Strangelove, I’m not saying our hair won’t be mussed, 15 to 20 million casualties tops!
The traditional method of fighting against infection, in the absence of a vaccine, has been quarantine. Quarantines are notoriously hard to enforce, since they require coordinated action by a large group of people, some of whom might find it in their interest to violate the quarantine. This is especially true if the population is composed of groups with different levels of vulnerability. This kind of thing is embodied in, say, infrastructure. In the late nineteenth century, many cities embarked on enormous and ambitious sewage projects, because sewage was a well known vector for disease. Though the wealthy had alternatives, they as a group were still vulnerable in cities, so they cooperated. Contrast this with AIDS, where one group is most affected, and a whole population can get by without too much worry about catching it. In this case, the vulnerabilities of one group can be seized by others as a political ploy, or they can be ignored, etc.
When we hear the comforting words, mathematically modeled, we have to remember that the modeling is only as good as the empirical data, and that is not very good. So far, mortality rates have differed considerably. Testing rates which are supposed to give us samples of the larger disease picture often end up giving us pictures of how much testing is going on – especially when we have wildly different samples.
What is brought into focus in these times of crisis is the expendability of a population in terms of the larger socio-economic system. In the 50s, when the AEC became aware that fallout was spreading a potentially lethal radiation load on a population located hundreds of miles from the bomb sites, they came up with a phrase that beautifully condensed the way established power thinks: the low use population. Indeed, is only a matter of time before some rightwing economist dances on the heads of all our dead parents and crows about the silver lining in terms of entitlement for all these old folks dying. Not to speak of the white settler offspring who have absorbed the idea that the virus has much more severe consequences in African American communities – communities that have seen their asset growth basically frozen or in decline from 2000 – and starts celebrating.
And this is the lesson of herd immunity in the C-Virus era: the herders don’t care.