The WHO made a thinly-veiled dig at Sweden's loose coronavirus lockdown, saying 'humans are not herds' and old people are not disposable

• On Monday, the World Health Organization blasted the idea of "herd immunity" for the coronavirus.
• "Herd immunity" is the concept that if enough people in society (the "herd") either contract or get vaccinated against an infectious disease, and thereby develop immunity to it, it could lower the risk of another serious outbreak.
• Sweden, a country which has resisted strict lockdowns, has suggested that Stockholm might reach herd immunity status soon. But scientists don't even know yet if a COVID-19 infection confers future immunity.
• Antibody tests being taken around the world suggest very few people have had the novel coronavirus anyway, suggesting a prevalence rate lower than 10%, and possibly as low as 1%.
• The WHO's Mike Ryan said it is "dangerous" to think that countries who've been "lax" about controlling the virus might "all of a sudden magically reach some herd immunity."
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The world is nowhere close to becoming immune to the coronavirus, and leaders at the World Health Organization Monday expressed outrage at the idea that some people might have to die in pursuit of a far-fetched virus-fighting strategy called herd immunity.

"This idea that, 'well, maybe countries who had lax measures and haven't done anything will all of a sudden magically reach some herd immunity, and so what if we lose a few old people along the way?' This is a really dangerous, dangerous calculation," the WHO's Executive Director of Health Emergencies Mike Ryan said on a call with reporters.

Ryan didn't mention any specific countries by name, but it was hard not to think about the high death rate in Swedish nursing homes as he mentioned that "in some countries, over half of the cases have occurred in longterm care facilities," where people haven't been "properly shielded."

Sweden has remained an outlier with it's relaxed disease-fighting strategy, keeping bars, schools, and gyms open during the pandemic, while also encouraging people to stay home when they're sick, social distance, and wash their hands frequently to avoid spreading the virus.

The term 'herd immunity' is meant to be used for vaccines, not illnesses — which can kill people

One of the benefits that health leaders in Sweden have thought they might, perhaps, acquire in this way, is something called "herd immunity."

The term is one that epidemiologists have been using for years to describe how a population that is by and large vaccinated can help protect its most vulnerable individuals (often, babies and immunocompromised people), including those who may not safely be able to get injections themselves, by making sure that most people in a community are immune to a disease. When such herd immunity is present, it's hard for a virus to spread.

But Ryan reminded his audience on Monday that this kind of herding strategy, when its used to talk about naturally-borne infections that we get from other people, rather than shots, has some sobering and sometimes fatal consequences which immunizations do not.

Put bluntly, getting people sick can kill.

"Humans are not herds," Ryan said. "I think we need to be really careful when we use terms in this way around natural infections in humans, because it can lead to a very brutal arithmetic which does not put people, and life, and suffering at the center of that equation."

Evidence so far suggests that herd immunity is a very far off goal for the coronavirus, anyway.

Studies suggest fewer than 1 in 10 people have gotten the coronavirus — that's nowhere near enough to protect our herd

Coronavirus blood tests, which check whether a person has developed antibodies to the coronavirus (meaning they've had a prior infection), are also coming back negative, which is another red flag for herd immunity.

"A very low proportion of the people that have been tested have evidence of antibodies," Maria Van Kerkhove, the WHO's technical lead for COVID-19, said. "The range is between 1 and 10%."

In the US, disease modelers, similarly, estimate somewhere around 2 or 3% of the country has been infected with the virus so far.

"There was an assumption as this disease spread around the world that we're really just seeing the severe cases, and the difficult cases, and when the sero-epidemiology comes, it will demonstrate that most of the people have been affected, and this will all be over, and we'll go back to normal business," Ryan said. "Well, the preliminary results from the sero-epidemiologic studies are showing the opposite ... The number of people infected in the total population is probably much lower than we expected."

Even Sweden's own public health agency has estimated that, at best, about a quarter of the population of bustling Stockholm might have contracted COVID-19. That is nowhere near what epidemiologists consider to be the very lowest bar for some kind of herd immunity, when around 60 or 70% of a population is protected against getting an illness. What's more, scientists don't yet know what kind of immunity a coronavirus infection might provide, meaning, just like the seasonal flu, this could be an illness that people catch more than once, and herd immunity doesn't apply.

Ryan was audibly troubled by the idea that the world would accept an infection spreading through a population, and even killing some people, to provide a kind of herd protection, especially one which scientists don't even know exists. He said that's not a calculus that any "responsible" country should be willing to take.

"They value every member of their society, and they try to do everything possible to protect health, while at the same time, obviously protecting society, protecting economy, and other things," he said.

"We need to get our priorities right as we enter the next phase of this fight."