6 things to say when someone asks: 'Why can't we just go for herd immunity to end the coronavirus pandemic?'

• Herd immunity by infection is not a viable strategy to fight the coronavirus pandemic.
• Chasing natural herd immunity could lead to 640,000 additional coronavirus deaths by February 2023. It also probably wouldn't work.
• Still, the recent Libertarian "Great Barrington Declaration", which proposes an end to COVID-19 restrictions and suggests trying to achieve herd immunity instead, received emphatic support from the White House.
• Last week, one of the declaration's authors, Dr. Jay Bhattacharya, debated Harvard University epidemiologist Marc Lipsitch.
• Their debate rendered 6 big reasons why herd immunity is a bad idea.

It's a tantalizing prospect to think that herd immunity could end the coronavirus pandemic. If true herd immunity were achieved, the coronavirus would no longer spread, and we could go back to normal life as we knew it before.

But herd immunity is tricky to pull off. It can only be achieved in two ways: by getting lots of people sick, or by giving lots of people an effective, safe vaccine. The goal is the same: to get a sizeable majority of the population resistant to infection, so that a disease can no longer spread among our collective "herd."

The consensus among epidemiologists is that chasing herd immunity without a vaccine would not work. It risks too many unnecessary deaths.

Even so, the concept has become a topic of conversation in households, on social media, on TV, in bars — with people asking: "Why not try it?" Those conversations gained steam last month when the White House propped up The Great Barrington Declaration, a document drafted at a Libertarian think tank suggesting that most people should try to go for herd immunity, encouraging infections among the world's young, healthy population.

"For people who are under ... let's say 60 or 50, the lockdown harms are, mentally and physically, worse than COVID," Dr. Jay Bhattacharya, one of the authors of the declaration said last week, during a debate hosted by the medical journal JAMA.

Opposite him was epidemiologist Marc Lipsitch from Harvard, one of the thousands of leading experts who signed on to a stinging rebuttal of the declaration, who explained why the approach is so dangerous.

"I think it's a great idea to look for creative solutions, but nobody responsible would abandon what we know works, which is controlling viral spread," Lipsitch said.

Their conversation threw up six overarching reasons why achieving natural herd immunity — the kind that doesn't require a coronavirus vaccine — won't work.

One: Nobody thinks it's a good idea to get everybody infected, but just targeting the young is near impossible

You'd be hard pressed to find a serious public health expert who thinks natural herd immunity will work.

Leaders in Sweden recently backtracked on their unique stab at herd immunity against the virus because it killed so many people in their nursing homes.

Bhattacharya name-checked Sweden as a good example of herd immunity done right.

But, when pressed, he agreed that letting anyone in the population get sick in order to drive up disease resistance in the community is not a good idea. "You should social distance when you can, definitely use masks when you can't social distance," he said. "All of the mitigation measures are really important."

Even Sweden's approach did not follow what the Great Barrington Declaration suggests: "focused protection" for the vulnerable, and focused infection of the young and healthy.

Bhattacharya asked listeners for their ideas about how to achieve this focused approach, and added a few of his own ideas, including employing rapid testing in nursing homes and multi-generational households, and isolating cases.

"We protect the vulnerable with every single tool we have," he said. "We use our testing resources. We use our staff rotations in nursing homes. We use PPE. We do all kinds of things."

The problem is, those ideas are already being tried across the US, to only mixed success. Nevada has found the US's new federal rapid testing protocol in nursing homes so unreliable that the state sought to ban them last month, a nursing home workforce already spread thin is getting sick, and case isolation is near-impossible to achieve in the dangerous pre-symptomatic phase of many illnesses, when people may transmit their virus to others before they even know they have it.

Two: COVID-19 has many long-term side effects that will impact lives and the healthcare system for years to come

The second issue with this idea of "focused protection" is that we don't actually know who we need to protect.

"For younger populations, and people who are less at risk, frankly, COVID is less of a risk than the lockdown," Bhattacharya said, reiterating that such closures harm people's psychological, mental, and physical health.

But COVID-19 doesn't just kill people. It also has devastating long-term effects on many of its survivors, including debilitating brain fog, hair loss, swollen toes and scaly rashes, tinnitus, and loss of smell.

The Centers for Disease Control and Prevention notes that nearly half (45.4%) of the adult population in the US is at risk for COVID-19 complications — including death — "because of cardiovascular disease, diabetes, respiratory disease, hypertension, or cancer."

Three: We don't actually know who COVID-19 kills and why

The argument for "focused protection" also ignores the reality of what we have learned about the coronavirus: it has killed people of every age, race, and sex, as it tears through community after community across the planet.

In the US, more than 45,500 people under the age of 65 have died from the coronavirus to date, according to the CDC.

It's impossible to know, before someone becomes infected, what their true risk is. Children have died. So have college students, and many others who did not necessarily have hallmark preconditions.

Scientists are still studying the virus to better understand how it works, but a unifying thread among severe cases may be how many ACE-2 receptors (which the virus uses to invade our cells) we have.

Four: Lockdowns save lives

Lockdowns, though they are an extreme disease-fighting measure, have saved tens of thousands of lives around the world, on nearly every continent.

It's true that there have been adverse consequences.

Many people have lost their jobs, shuttered their businesses, missed doctor's appointments, experienced more loneliness, and started drinking more alcohol. When schools are closed, more kids go hungry, and education gets interrupted too. Domestic abuse, child abuse, substance abuse, and suicidal ideation have all gone up in recent months in the US.

"I have not been able to go to church in person, really, in seven months," Bhattacharya lamented.

However, these measures have bought critical, life-saving time for developing vaccines, formulating drugs, and discovering best practices for patient treatment. "Six months from now, [a] case might be prevented by vaccination, or might be treated by a better therapeutic," Lipsitch said.

Bhattacharya also argued that lockdowns are "the single biggest generator of inequality since segregation."

But that is a deeply misleading statement. Racial inequality, for example, has not been generated by the pandemic, if anything it's only been unmasked.

"Obviously, the African-American community has suffered from racism for a very, very long period of time," Dr. Fauci told members of Congress in June. "And I cannot imagine that that has not contributed to the conditions that they find themselves in, economically and otherwise."

Five: Getting rid of the virus is possible, and it doesn't require killing people

Bhattacharya, and other backers of herd immunity, often peddle a false dichotomy between lockdowns and "normal life," with no grey area or room for virus-fighting in between.

But that either-or approach doesn't take into account how much mitigation measures like distancing, avoiding crowds, and getting everybody wearing masks can really help slow viral transmission.

Besides, the US hasn't ever really, truly tried to lock down yet. Even in the spring, "we really functionally shut down only about 50%," Fauci recently told members of Congress.

Countries including Australia, New Zealand, and China have already achieved the "impossible goal" of zero (or, near zero) COVID, and have largely gone back to normal life after strict lockdowns. Taiwan even did it without locking down at all, by instituting strict screening and surveillance measures, effective isolation and quarantining, and widespread masking.

Six: Natural herd immunity probably won't work for this pandemic, no matter how hard we try

The US, like everywhere else in the world, still has a long way to go to hit even some of the lowest posited herd immunity thresholds, which require 50% (or more) of the population to be exposed, and subsequently immune. At best, only around 10% to 20% of people nationwide have been exposed.

But even if everyone was to become exposed to the virus, natural herd immunity likely still wouldn't work.

This is because of the way that our immunity against all coronaviruses — from common colds to this novel coronavirus — wanes over time. Immunity to this virus through prior infection is not definitive, or lasting: coronavirus reinfections are possible, and they're happening in some rare cases already.

That's why serious scientists agree it's better to wait for a vaccine, and build up our collective immunity against the virus simultaneously.

"Humans are not herds," the WHO Executive Director of Health Emergencies Mike Ryan said in May, slamming the idea. "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."

One projection suggests that attempting herd immunity in the US would result in 640,000 deaths by February 2023.