The term "Herd immunity" only refers to those who live. Please stop using it?

Apologies if this is perceived as a double post. There was a thread on the News page, and I thought this discussion needed its own thread: for definition, for education, and for sharing.

Speaking as a blood donor, I wish the term “herd immunity” would be banned from the known universe.

"Herd immunity" only applies to the patients who live through it.

For reasons I cannot fathom, some earthlings believe that COVID-19 is like a tub of ice cream at a birthday party: when it’s gone, it’s gone. The piglets at the front of the line get more than their “fair share.” The sad puppies at the end of the line get a dribbling spoonful, just enough to remember what ice cream tastes like.

This disease is not a limited-supply item.

This disease is like a forest fire. The more fuel [i.e., patients] you provide, the more it grows.

Scripture tells us very, very plainly the nature of fire (Proverbs 30:15-16). No forest fire ever cried, “I am full; I am weary; please stop feeding me.”

Nowadays we would cite Terminators. “It cannot be reasoned with. It cannot be bargained with. It doesn’t feel fear, or remorse, or pity, or fatigue. And it absolutely will not stop, ever, until you are dead.”

Obviously more people survive this disease than survive Terminators, or even forest fires. But it is because both are world-famous that I get exercised about this offensive and inaccurate term.

I’m not trying to frighten anyone. With self-discipline, we can minimize exposure until a vaccine is found.

The only way we will have “herd immunity” is if everyone catches this disease and it weeds out countless numbers of children of God. Those who survive are immune. How nice for them.

Or when we find …

1: a treatment.
2: a cure.
3: a vaccine.

Please know that I am not aiming at anyone, my fellow posters, but at the term “herd immunity.” It is inaccurate, repulsive, and inexpressibly cruel. But I also know that many people innocently use the term without knowing what it means.

{/end G-rated rant}

(And yes, we blood donors try to be healthy. We have to answer about 70 questions describing our habits. Have our bodies visited Great Britain from 1983-1986? Mad cow disease. Whose genitals have visited from, well, ever? STDs. Did your mouth partake of food at an establishment that has been identified on See-List? Legionnaire’s outbreak. Et cetera. But for all our care, no blood donor can be said to be “immune” to anything if we haven’t been vaccinated against it.)


Most people have no idea what herd immunity is.

It’s not really immunity at all.

It just means that when a certain large percent of people are immune from disease x, you don’t get it because no one in the herd has it to give to you.

That’s why it’s usually no big deal when you say you wont get your kid the MMR vaccine - no one is getting those diseases.because they did get the vaccjne. But when 10-15 percent of folks don’t vaccinate, the non vaccinated population gets so large that MMR becomes a possibility because those illnesses still lurk in the world.

We are nowhere near herd immunity for covid.


Quite right. We aren’t cows.


I understand your objections, but I don’t think you have this quite right. Herd Immunity occurs when a sufficient number of the population acquires immunity to a disease such that it is unlikely to be passed uncontrollably through the entire population. Your analogy to a forest fire is actually a pretty good one. If there is no fuel, the fire cannot spread out of containment. So just as firefighters will purposefully do controlled burns in order to prevent an out of control wildfire from breaking out of containment, a herd immunity strategy seeks to do the same thing with a virus. This is where the analogy breaks down though.

The first analogy assumes that everyone catching the disease is destroyed. That isn’t the case. In the case of COVID-19, certain segments of the population are at increased risk. However, many people catch the virus and experience mild or even no symptoms at all. The point here then is to contain the disease in order to protect those who are most vulnerable (those with significant co-morbidities, and the extremely aged).

There are two ways to obtain herd immunity. The most preferable is to create a vaccine that can be given to large numbers of the population such that they develop the antibodies to prevent the virus from breaking out of containment. The problem is that we are probably a year to a year and a half out from a vaccine, assuming we can successfully generate a vaccine (there are no instances of successful vaccines for coronaviruses such as the common cold), and also assuming the virus will not further mutate such that a vaccine would be rendered unusable in a short amount of time. So obtaining herd immunity this way has two serious flaws: 1) our ability to successfully generate a vaccine is questionable; and 2) the timeline is such that it is virtually unworkable if we are to allow people to perform the day-to-day activities needed to provide for ourselves.

The second option is to allow a controlled avalanche. So at ski resorts they will shoot off cannons to cause avalanches in the hopes that unstable snow packs will be eliminated in a time and manner that prevents it from occurring when the ski slopes are populated (when we are most vulnerable). Using this strategy, we allow healthy and young people to do normal activities using PPE and other risk mitigation to limit the spread, but allowing some to get the disease and develop antibodies to it. The hope being that if enough of the population does so, and we maintain risk mitigation over portions of the population that are most at risk, we can contain the spread to protect those who are most vulnerable.

We might not like it, but those are basically our options, and we need to be able to talk about it in rational discussion.


No, I don’t think I will.

A lethal virus is going to kill a certain amount of people no matter what. Thinking we have the power to stop death from a naturally occurring organism is the height of hubris. Sugar coating that fact doesn’t make it untrue.


Do you approve of the Merriam-Webster definition?

herd immunity
: a reduction in the risk of infection with a specific communicable disease (such as measles or influenza) that occurs when a significant proportion of the population has become immune to infection (as because of previous exposure or vaccination) so that susceptible individuals are much less likely to come in contact with infected individuals


There are those who are exposed and actually contract the disease, leading to death, or to severe but not fatal disease, as well as those who have it to a moderate degree. Those who survive apparently don’t get it again, though that is not confirmed.

Besides those persons, there might be a population “lightly” exposed, perhaps over a long time, but do not contact it. Isn’t it possible that these people have greatly reduced chances of contracting it?

NY City now has an astonishingly small rate of new cases, even though the ongoing testing for current Covid and for Covid antibodies shows the great majority of the population apparently tests negative.

Yet since June NY City has reopened part way, and the suburbs even more. Why so few new cases in July? (yesterday 1.1 percent of those tested were positive). These 1.1 percent were not a random sample, which likely would have been lower.

Truthfully, I disagree with it. To me, “immune” is defined as: my immune system has the tools it needs to protect me.

Whereas isolation limits the amount of fuel, but does not make the disease less deadly to the fuel it does consume.

There is a difference between billions of people never being exposed to the disease (therefore they cannot pass it along) versus billions of survivors of the disease who cannot pass it along because there’s no one left who hasn’t had it.

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Not necessarily - we have herd immunity to smallpox and things like

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Well, let’s look at this.
With a 96+% survival rate, most people that get the virus will survive.
So straight away the analogy fails. A tree on fire will be consumed utterly. A human with Covid may well survive.

Now of these people that survive, how many have built an immunity to it?
If enough have an immunity, then the virus no longer is able to run out of control.
It would become a rare thing if someone with an active infection encountered someone else susceptible to the virus and passed it along.


Isaiah 41:10

Fear not, for I am with you;
Be not dismayed, for I am your God.
I will strengthen you,
Yes, I will help you,
I will uphold you with My righteous right hand.’

Speaking as an M.D., looking the latest reports from Stanford University, The University of Southern California, and University of Bonn, in Heinsberg, Germany, shows **Covid-19 has a greater prevalence than previously believed by 40 - 50 fold This means there are MANY more asymptomatic carriers AND individuals who have already had the disease AND recovered / immune walking about than was previously suspected.

Based on a random sample of 863 adults from a marketing pool in Los Angeles, approximately 4.1% of the population has antibody to the virus, which, corrected for statistical error (considering sensitivity and specificity of the test), means 221,000 to 442,000 adults in Los Angeles County have had a Covid infection. The estimate is 28 to 55 times higher than previously calculated in April.

Stanford University epidemiologists, pegged the fatality (percentage who die after contracting the disease) rate at between 0.1% and 0.2%. (1/1000 - 2/1000). An affiliated team from the University of Southern California (USC) this week reported a similar fatality rate in Los Angeles.

In May, 2020, Dr. Fauci admitted "the mortality rate may be as low as 1%, similar to seasonal flu."

The Stanford and USC mortality rates are 1/10 that of Dr. Fauci or 1/10 that of seasonal flu.

**Mortality rates vary by many different factors such as country, patient age, preexisting conditions, time period studied, etc.

The University of Bonn study in Heimsberg, Germany (the hardest hit region of Germany) calculated a mortality rate for Covid-19 of 0.37% (about 4 in every 1,000 infected persons, ten times lower than the WHO calculated figure). This is similar to the USC and Stanford conclusions.


Some live, some die - that is the reality of life. Even the terrible 1918 Spanish flu at some point ceased to have it’s massive deadly effect, most likely because of the “herd immunity” concept.

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Not smallpox. When everyone was immunized, we obtained herd immunity but we no longer vaccinate for it because the only bugs are securely locked away. If it got out in the wild again, it would run rampant through the population until we inoculated everyone again. This scenario is becoming more likely with measles. We still vaccinate for it because it’s still in the wild but as more and more choose not to vaccinate themselves and their children, we could see some horrid clusters of measles. Again, it could run rampant through areas that don’t vaccinate until they once again began getting vaccinated. If you live in an area with a high vaccination rate, you are still enjoying the herd immunity if you don’t vaccinate. Any contact with a measles case would mean you’d likely get it, too.


No, our bodies live or die, but all of our souls live for eternity in heaven or hell.

Death from disease is no accident. It is a destiny for some, but not for others. God has very fine control over ALL events. God can even control "herd immunity."

Matthew 10: 30 - 32

30 But the very hairs of your head are all numbered.

31 Fear ye not therefore, ye are of more value than many sparrows.

32 Whosoever therefore shall confess me before men, him will I confess also before my Father which is in heaven.

Actually, the latest research is starting to tentatively point towards herd immunity without 75% of the population getting it. Half of us may already have some cross immunity from other coronaviruses.


Do some googling on T-Cell immunity and you start to think NYC might actually have achieved something close to herd immunity. If (and it’s a big if), 50% if us have some type of immunity already, and the actual infection rate in NYC is 10 times their rate of confirmed cases ( not that big of an if), then they might be there. That might explain why they have not had a second wave.

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If only I could know the state in which you live, I could be sure to live elsewhere.

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I’ll tell you just so you do, I live in Kentucky, so be sure not to visit.

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Many thanks!

Herd immunity is a term used by immunologists, epidemiologists, and infectious disease specialists.

It is a legitimate medical term used by medical professionals and scientists. It is not meant to denigrate human beings or compare them to cows.

I remember sitting through my immunology course in college back in the 1970s, and the term “herd immunity” was described and discussed by our very knowledgable professor who had packed lectures because the course was so interesting and he was a recognized expert. No one took offense back then, and there is no need to take offense now, and certainly no reason for lay-people to stop using the phrase, as long as they use it correctly.

AND–it is a legitimate strategy for defeating COVID-19, and certain nations (e.g., several of the Scandinavian countries) have tried it.

My problem with the strategy is that it appears that becoming infected with the COVID-19 virus does NOT seem to confer immunity on patients, who have reported getting well, and then getting re-infected. I hope I am wrong about this, and perhaps others have read some papers that refute what I am surmising–and it is just surmising based on what the “media” (whom we all trust–not!) has been reporting.

That’s kind of scary, because if getting COVID-19 does not mean “immunity” (usually because of antibodies produced that protect against future infection by the same virus), then we cannot use a “herd immunity” strategy because…well, because no one will be immune.

Now it’s possible that these people never really got “well”. It’s possible that they feeling better, but still harboring the virus in their system, and eventually it manifested its nasty self again and caused a recurrence of symptoms. I hope this is the case, but the only way to know is to test for antibodies, and at this time, the antibody tests that I know about (lab tech here, working in microbiology for over 40 years!) are horribly unreliable, with a 50/50 chance of being correct. I would never play a game with those odds!

So as much as I hate to say it, as much as I wish we could adapt a “herd immunity” strategy in the U.S. and just let the virus infect most of us, I don’t think it’s safe until we know more about the mechanism of infection and immunity of the COVID-19.

Yes, , I know that a herd immunity strategy means that some of us would die, but that happens with ANY infectious disease. The fact is that we use herd immunity to protect people from all kinds of infectious disease in the U.S.–if we DID NOT use the strategy of “herd immunity,” immunizations would be REQUIRED FOR EVERYONE BY LAW and those who opt out would be considered in violation of the law–and I really don’t want that kind of policy to become our national policy, do you? Herd immunity protects those who, for whatever reason, choose not to be immunized against certain infections (and there are legitimate medical reasons why people cannot be vaccinated).

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