San Francisco may be first major US city to hit herd immunity, experts say | Hacker News Reader

San Francisco may be first major US city to hit herd immunity, experts say

theguardian.com

60 pointsdrx51 comments

The interesting thing about San Francisco now is that people still wear their masks outdoors despite all the excellent news and the number of new cases going down. Not that that's a bad thing.

It'll be interesting to see what happens on June 15 when the mask mandate goes away in CA (theoretically).

> people still wear their masks outdoors despite all the excellent news

The whole spring pollen thing hasn't hit me in any way this year - the cottonwood seeds are also in the air.

I notice that I don't feel as bad about all of that with an N95 this year, though I'm conserving some N95s for the eventual fire season this year.

I’m sure there will still be a good number of people wearing them places like stores for a while, since we get so many tourists. I’d bet people continue to think, “why not?”, while it’s still spreading.

Most people spend 99% of their time with friends, family, or trusted coworkers anyway.

"The interesting thing about San Francisco now is that people still wear their masks outdoors"

This probably depends a lot on the neighborhood.

I'd be curious to know what percentage of people in poor neighborhoods like the Tenderloin and in homeless encampments (who are some of the most vulnerable) are wearing masks.

I believe that Cal/OSHA will still require masks indoors unless everyone inside is vaccinated.

Edit: "Indoors, fully vaccinated workers without COVID-19 symptoms do not need to wear face coverings in a room where everyone else is fully vaccinated and not showing symptoms. However, where there is a mixture of vaccinated and unvaccinated persons in a room, all workers will continue to be required to wear a face covering."

https://www.dir.ca.gov/DIRNews/2021/2021-58.html

That's bizarre because we've known for a long time now that Covid doesn't really spread outside. Doubly bizarre if vaccinated.

I think its social pressure. Prior to covid we always called masks PPE or Personal Protective Equipment, and you wore PPE mostly to protect yourself. When covid hit we told everyone to wear PPE but that you were doing so to protect everyone else and not yourself - that you needed to rely on everyone else wearing masks to protect yourself. So we end up with social pressure to wear masks and you wear one to show that you are doing the right thing.

The new cases going down are at least partially because of continued mitigation work.

I genuinely don't understand the anti-mask mania, I really don't. Mask use is almost free. Virtually no activities are precluded by wearing a mask (even eating, frankly, just lift it up and put it back to chew). Masks should be the first mitigation rule enforced in a respiratory disease environment and the last one relaxed.

Restaurant and event closures, quarantines, travel restrictions, testing requirements, vaccine registries... All of those have significant real costs and should be done only when masks aren't sufficient. And they should all be relaxed first before we give up masks.

But yet, everyone points to masks as somehow the opposite: in the minds of so many people (even seemingly scientifically literate people here) they're the worst thing imaginable, and... why? They're just masks. Wear 'em. It's cheap and easy.

They are annoying to wear. They make my beard itch. They make my glasses fog up. They make me feel overheated if it's warm out. My airflow feels noticeably restricted if I am exercising, even with ordinary non-N95 masks. They are easy to lose track of, which is highly annoying when I am otherwise ready to leave my apartment.

Masks fucking suck.

Whole careers are spent wearing masks, though. I mean, fine. I find them mildly annoying and you think they're the devil's work. But we both agree that we should be opening restaurants and theaters before we relax mask use, right?

You don't need to wear a mask if you're fully vaccinated because the vaccine is over 90% effective at preventing infection

https://www.medrxiv.org/content/10.1101/2021.06.01.21257987v...

And that's the kind of innumerate thinking I don't understand. Masks aren't an either/or thing. Say masks are maybe 60% effective (there's no real consensus and good science is hard to come by). A mask-wearing vaccinated person is now 96% protected. Add that to staying outside (maybe another 75% or so?) and you get to 99%. Every bit helps, which is one of the reasons why we're reaching herd immunity.

Now, you're right, there's a cost tradeoff. If everyone is at 99% it would be pure insanity to close restaurants, say. But... masks? Leave them on, until it's dead. Again, this is the cheapest mitigation we have. Roll back every other protection first. Send people back to the office. Open up the stadiums. Start hugging again. Lift the visa restrictions. Visit the grandparents. Do all that stuff first before relaxing mask use.

Just wanted to say you've made very good points.

I think it isn’t necessarily innumeracy to move past napkin math 18 months on. People have had the time to see the results of several cycles of behavior modification and perhaps aren’t interested in participating further.

While you’re at it why don’t we mandate everyone wear latex gloves all the time? No biggie.

And just always have hand sanitizer on your person. Just a small bottle so not much of a problem.

Can we just mandate people select a group of 100 people they will interact with? Almost nobody has more friends + family to see than that so it’s hardly an issue when you think about it.

You have this backwards: mandates must be continually justified beyond a reasonable doubt, not the reverse. Remember: mandates are dictating how others live their lives. Just because something isn’t that big a deal to you or aligns with your values doesn’t mean imposing that on someone else with the threat of government enforcement is reasonable in the slightest. Wear your mask, they are tools used to good effect, but requiring others to wear them is a step that should be continually challenged with all available true evidence and aggregate personal values - as should any mandate or law.

This is a giant list of strawmen. I'm not arguing for a mask mandate, I'm saying that masks as mitigation have been and continue to be good strategies (and in particular very cheap ones) and that we want to continue to use them until the pandemic is actually controlled (vs. just shrinking) and not incessantly mock people who continue to use effective means of disease control.

It’s telling how any mention of the fact that masks aren’t really that effective instantly is branded ‘mocking’. Especially while the pro mask Facebook groups have spent the last year pointing fingers at ‘anti mask Karens’.

I think some of your points are valid.*

However, if people are to wear masks until covid is truly gone, you may be asking people to wear masks forever. I think once covid is less of a population risk than a bad flu, all mandates should be dropped.

You should also disregard anti-vaxers* from the stats. If they want to die, fine. So at this point we have anti-vaxers, kids under 12, and some very rare medical cases left in the US now. With community spread where it is (low and dropping), the flu is genuinely scarier for kids under 12, and likely to kill more.

There is no quantitative reason for any restrictions at this point.

* I'll note the first thing that should have been prioritized is un-banning vaccines. *Anti vaxers in this context means anyone who at this point has had months to get a free vaccine and still hasn't, they have now earned the label.

FWIW, I believe the guidelines do not recommend wearing a mask while exercising outdoors. I think partially because you're moving relatively quickly and partially because it's not very practical.

I hate masks too. But the moment you realize masks are more about protecting the public from transmission when you happen to suddenly get sick and isn’t about your protection, you’ll literally breathe easier by choosing to wear the cheapest masks. You’re better off obsessing about who you’re around and washing your hands if you’re worried about Covid. That’s why wearing N95 and fabric masks is overkill. Buy the mass produced disposable black (not thick fabric) masks. They look better than the blue ones. And if you wear glasses, they have slightly better airflow. Put a box in your car, a box in your house, a box on your desk. And then just grab and go! It’s surprising to me that we’ve been through a year of the pandemic and people still can’t adopt a change in routine!! And you don’t need a mask while exercising!!!!

I genuinely do hope we see widespread behavioral change, where people are more considerate, and choose to wear masks... when they are sick or recently exposed to someone who is.

I am not sick though.

Are you unconcerned about asymptomatic transmission? As I understand it, a big reason why there's a pandemic is that you might not necessarily know whether you're infectious.

Asymptomatic individuals are indeed less infectious on an individual basis, but I know of at least one study [1] which purports to show a lot of transmission from asymptomatic and pre-symptomatic people.

[1] https://jamanetwork.com/journals/jamanetworkopen/fullarticle...

Not only am I not sick, I am vaccinated, and vaccines are widely available where I live.

So no, I have absolutely no concern for asymptomatic transmission.

>Mask use is almost free.

They cost $10 for a box of five here for masks that ideally should be one time use, if used properly. I've noticed a ton of 'mask pollution' over last year. Masks lying on the ground, masks in waterbodies, masks on the beach.

The only places that offer masks on entry are government run places, despite it being legally mandatory everywhere. Otherwise, you pay out of your pocket.

In the end, i see people wearing masks incorrectly everywhere, we have such rules as 'wear a mask inside, unless you're sitting at a table' Which makes absolutely no sense.

The masks used by 90% of people use are no better than tying a t-shirt over your face.

The way it's been implemented most places, people's attitudes towards it both the for and against people and generally everything with masks are over the top or not enough.

If you are in a small enclosed place in close proximity to other people and you wear an appropriate face covering you don't touch and you dispose of properly afterwards or wash as soon as possible, you are doing something effective.

Otherwise, it seems to be more about appearances and making people feel better than anything.

Hell, most of the covid signs at businesses around here pretty much say everyone needs to wear a mask so 'people feel comfortable'.

> The masks used by 90% of people use are no better than tying a t-shirt over your face.

In fact tying a t-shirt over your face provides decent protection. This stuff was all studied. You're right that good masks with good seals work much better than amateur cloth masks. You are wildly wrong to imply as you do that they don't work. They clearly do.

Again, I just don't understand the irrationality here. They're just masks. They're cheap and effective, continue to be, and shouldn't ever have been big deal. If people want to wear masks for a little extra protection let them wear a fucking mask for God's sake. Why must everything be a politicized fight?

I live in Detroit and was just in La and the difference was insane despite Detroit being roughly 30% percent vaccinated, almost no one wears a mask whereas in LA everyone was everywhere I went

I live in NYC where mask adoption was very high... it has been dropping pretty aggressively since the CDC and the state updated their guidelines.

You actually never needed to wear a mask outside. Even in Wuhan, the number of outdoor transmissions cases was next to nil, and they have a lot higher population density.

> You actually never needed to wear a mask outside.

This claim is patently false. Even though outside spaces are safer than indoors, it's still possible to spread covid-19 outdoors, moreso if you do not respect social distancing.

https://www.bbc.com/news/explainers-55680305

https://www.mayoclinic.org/diseases-conditions/coronavirus/i...

It seems that anti-maskers grab the claim that masks are not necessary if you're sitting quietly at a table on a plaza on a sunny day while preserving the min >2m social distancing, but completely disregard all other scenarios such as the journey to said plaza and unexpectedly finding yourself in high-risk scenarios while you move around.

To put things in perspective, there are documented cases where COVID spread through person's that stopped to chat outdoors while not wearing a mask.

What makes this sort of argument regarding the use of mask particularly dangerous is that it starts with a premise based on a very specific scenario combining key factors that are known to be safe (i.e., sit outside without a mask on a sunny day while preserving social distancing) but ends up trying to justify discarding each and every key safety factor (social distancing while outdoors in sunny, hot days, and even the need to wear a mask while going to a public place).

Lastly, although wearing a mask is important to keep you from catching COVID (or any airborne respiratory disease) the main goal of wearing a mask is to ensure that asymptomatic people (and specially symptomatic people) don't unwittingly spread the virus.

This claim is patently false. Even though M95 masks were found to be beneficial against respiratory viruses in a clinical environment, disposable or cloth masks haven't - and currently real-world testing of mask efficacy is nearly impossible due to all the other measures that go along with mask mandates.

https://www.rcreader.com/commentary/masks-dont-work-covid-a-...

https://www.cambridge.org/core/journals/epidemiology-and-inf...

https://academic.oup.com/cid/article/65/11/1934/4068747

It seems that pro-maskers vastly overestimate the efficacy of mask wearing, especially of the kinds of masks most commonly worn in public. This over-exaggerated focus on mask wearing disregards all the other factors that contribute to lowering risk in all scenarios.

To put things in perspective, there are documented cases of people going blind from COVID while indoors. This is a bullshit point, and has no statistical bearing, but it's true.

What makes this sort of argument regarding the use of masks particularly dangerous is that it is only about 50% true, but treated as if it were gospel and everyone who doubts the policies is branded as dangerous by the people in power.

Lastly, although wearing a mask is not likely very important (though likely somewhat beneficial!) to keep you from catching COVID (or any airborne respiratory disease) the main goal of wearing a mask is to enforce conformity through social cues, thereby treating people like cattle and not allowing any reasonable discussion or nuanced approaches to better solve problems during the pandemic.

> This claim is patently false. [...] real-world testing of mask efficacy is nearly impossible due

"Patently false" is vastly different to "unsubstantiated."

In addition, here is an entire page of studies substantiating mask efficacy: https://wwwnc.cdc.gov/eid/article/26/10/20-0948_article

The point was to show that the OP has a false-confidence in their arguments that could easily be countered by more nuanced takes on mask wearing.

No one is doubting mask efficacy, just their degree of efficacy. All of the studies shown do not justify mandating the use of cloth or disposable masks outdoors, or even indoors. They all show that people should be wearing M95s or better if they want substantive protection.

What you're suggesting is akin to wearing gloves in public - which while probably somewhat safer, is not really a key driver of stopping spread.

What's worrying is that not only are your arguments heavily flawed, but we can extrapolate 99% of your political views just by looking at one of your scientific takes. For anyone wondering, no I'm not a Republican.

> The point was to show that the OP has a false-confidence in their arguments that could easily be countered by more nuanced takes on mask wearing.

That's a gross misrepresentation of the facts, and one which flies in the face of reason and reality.

It's widely known that basic and low-effort protective measures such as social distancing, washing hands and wearing facial masks, are effective in reducing the spread of covid-19 and other airborne respiratory diseases. The point was never that these basic, low-effort measures are not full-proof.

The whole point is that they are effective, they are demonstrably effective, and they require little to no effort to implement.

For some reason, anti-maskers try to move the goal post by pretending that a basic protective measure is either full-proof or is not worth doing at all, which boggles anyone's mind.

It's safe outdoors, masks or not. You can wear a mask if you want to, but it won't make a difference.

> For some reason, anti-maskers try to move the goal post by pretending that a basic protective measure is either full-proof or is not worth doing at all, which boggles anyone's mind.

I don't know about other "anti-maskers," but for me, it's about the precautionary principle [1]. If a "basic protective measure" is not foolproof, then maybe the downsides of such a measure outweighs the benefits, and before we decide, collectively, to change our habits, maybe we should think hard about those downsides.

Yes, there are downsides to masks: reduced oxygen, keeping captured bacteria close to your face for long periods, etc., made worse by the fact that people, by and large, do not rotate or clean their masks properly. In other words, experiments in a lab that study the effectiveness of masks when used properly do not match the reality of how people actually use masks.

In other words, in science, all factors matter. [2] And pretending otherwise is disingenuous.

[1]: https://en.wikipedia.org/wiki/Precautionary_principle [2]: https://gavinhoward.com/2020/08/in-science-all-factors-matte...

> If a "basic protective measure" is not foolproof, then maybe the downsides of such a measure outweighs the benefits

Pray tell, what are those collosal downsides that render such an effortless thing like wearing a mask in public such a prohibitively costly endeavor?

We don't know. That's why the Precautionary Principle is so important. It is built on the assumption of "We don't know, and we don't know what we don't know, so we had better be cautious."

> We don't know.

Bullshit. People have been wearing protective equipment such as masks for decades, and the negative effects are none.

The anti-maskers' irrational tirade about even low-effort/high-reward protective measures that are demonstrably safe and terribly trivial to pull off is the key factor in this pandemic taking so long to just die off, and you should be ashamed of yourself for contributing to this state of affairs.

> People have been wearing protective equipment such as masks for decades, and the negative effects are none.

Have you yourself seen studies that say the negative effects are none? If so, point me to them; I've only found a few, and they all seemed flawed.

> you should be ashamed of yourself for contributing to this state of affairs.

I have no shame in defending true science against propaganda.

[1] is a blog post I wrote about masks and carbon dioxide, where I wrote a model and ran it on various parameters. The net result was always the same: there was half oxygen and half carbon dioxide behind the mask.

Dr. Anthony Fauci knew that masks were ineffective. [2]

The CDC did a study that failed to show that masks were effective. [3]

Another study showed that masks did not work. [4]

There is a review of older papers concerning masks [5] as well as a follow-up. [6] (Though I do not know the political bent of that website; the review may be cherry picked.)

In other words, there is evidence that masks don't work and that there are downsides. If masks reduce oxygen, which makes us more vulnerable to disease, and they don't work, it's possible that the masks actually made things worse, by making us more vulnerable while doing nothing.

That is why I will never feel shame for my "irrational tirade" because it's not a tirade, and it's not irrational.

[1]: https://gavinhoward.com/2020/08/masks-and-carbon-dioxide/

[2]: https://www.msn.com/en-us/news/us/fauci-said-masks-were-not-...

[3]: https://www.cdc.gov/mmwr/volumes/69/wr/pdfs/mm6936a5-H.pdf

[4]: https://www.medrxiv.org/content/10.1101/2021.05.18.21257385v...

[5]: https://www.rcreader.com/commentary/masks-dont-work-covid-a-...

[6]: https://www.rcreader.com/commentary/still-no-conclusive-evid...

> The net result was always the same: there was half oxygen and half carbon dioxide behind the mask.

Fascinating. Oxygen normally only makes up 21% of breathable air - it would seem that masks are increasing oxygen levels. In addition, where is your null hypothesis test?

The model only tests how oxygen and carbon dioxide replace each other, not nitrogen. So 50% of the 21% is oxygen, the other 50% is carbon dioxide.

Of course, it could be even worse, that carbon dioxide starts replacing the nitrogen behind the mask. More testing needed.

10% CO2 (> 40000ppm) is lethal. Have I been brainwashed to ignore the people dropping dead on the streets?

The carbon dioxide is only replaced in the volume behind the mask. If that is not a big volume compared to a full breath (and it isn't), then the carbon dioxide you're breathing in isn't 10%. It's (v_mask * 0.21 * 0.5)/V, where v_mask is the volume behind the mask, and V is the full volume of a breath.

> political views

What the hell has that got to do with anything?

The fact people study the effectiveness of masks rules out your point. Suggesting it is some method to enforce conformity is the step where it derails into conspiracy theory tier rambling and fear mongering.

Yes it is a valid question, are masks effective, and as you actually point out, people study it. But somehow that doesn’t count to you, and that is somehow being censored?

Masks do not have to protect everyone perfectly to have an effect. If it reduces the spread in a statistically significant manner over the entire population that is enough. Dampens chains of transmission and growth. Seems fairly basic that putting a barrier to catch or deflect particles is not a bad idea. I think if it reduces transmission even by 10% it’s worth it. Yes maybe it’s not perfect, but I think the studies suggest it does help to some small extent. Combine that with vaccination, distancing, habits you end up beating covid.

Normal people are not experts in statistics and virology. I think that the medias job is to try and promote and distill what the current consensus of the experts is. You want society to go along with it. We should try and follow their advice. Are there mistakes? Yes. As we get new information, the model changes. That is science. Does this need to be a disclaimer? Maybe.

Recently however many people are just radicalised and take an expert position as some sort of conspiracy. They want to question things that they know nothing about, and it doesn’t end up been done constructively in good faith.

Society by large doesn’t seem equipped at the moment to handle and properly discuss these issues. Maybe it doesn’t even have. Seems like specialisation is what we do, so we should go along with experts for the most part.

If you point out all the times where experts were wrong, well the fact that over time they were found out and advice was changed, is actually a sign that the system works. Maybe unfortunate for some individuals but for society as a whole, progress is made.

Assuming that if masks reduce the transmission by 10% is automatically worth it is not a good idea because we need to know the downsides of masks and how bad those downsides are.

In science, all factors matter, not just efficacy. [1]

[1]: https://gavinhoward.com/2020/08/in-science-all-factors-matte...

> Even though M95 masks were found to be beneficial against respiratory viruses (...)

You're contradicting your claim.

> It seems that pro-maskers vastly overestimate the efficacy of mask wearing (...)

You're desperately trying to use red herrings and unsubstantiated accusations to move the goal post, specially after already admitting that indeed you are fully aware that wearing a mask are beneficial against respiratory viruses.

No one claimed masks are full proof protection against COVID.

The whole point is that, and it always been, that masks are a low effort method to effectively (albeit not perfect) mitigate how the virus spreads.

Moreover, the main point of the mask was never to stop us from contracting COVID. It's effect to lower the chances of contracting the disease are nice-to-have. The whole point is that wearing a mask effectively reduces the odds of carriers (asymptomatic or not) of unwittingly spreading the disease. It is known that COVID spreads through droplets expelled by carriers through their airways, and placing a mask in front of their airways stops them from spreading by acting as a filter.

This is not hard to understand. Low-effort, high-reward.

Great! Hope the rest of the US and World catches up soon.

What percentage of the population do you need to vaccinate against Covid to reach herd immunity? People who are fully vaccinated are testing positive for infection and presumably can transmit the disease (although at a much reduced rate).

And it looks like ~10% of SF is under 12, so unvaccinated plus another 20% of those over 12, so maybe 20-25% of all people are unvaccinated. Is that still herd immunity?

It's about 65%

As I wrote on HN early 2020, Wuhan and Shanghai had direct flights to SFO and LAX of 50,000 passengers per week. No doubt corona was in SF very early, possibly late 2019.

SF got herd immunity from infections, which is why it was rare that we came anywhere close to ICU capacity. I watched the graphs daily for months, and while the rest of the country was losing their minds, we just didn't see much of a dent, typically in the range of 10% of total beds.

The only hysteria was from Newsom, who has ambitions of running for President.

Reply on news.ycombinator.com