How’s it going in Los Angeles with the pandemic?

The numbers in LA are absolutely dreadful. Daily new cases, hospitalizations, and deaths are at all-time highs.

The current case numbers make the mountain of cases this summer look like a molehill. In July I worried that a COVID death rate in the 40s per day would make COVID a contender for the leading killer in LA County. The current death rate is twice that. Many LA ICUs are at or near capacity.

But a vaccine is on the way. Everyone’s talking about it!

Actually, several vaccines are on the way. A vaccine developed by Pfizer-BioNTech has just been approved. Healthcare workers and residents of long-term care facilities have been receiving it for about a week. Moderna’s vaccine was authorized this week, and its first doses should be in peoples’ arms by the time you read this. Other manufacturers have vaccine candidates that will seek approval once their testing trials are complete.

I’m worried that the vaccines were developed so quickly. I don’t want to get a vaccine if they’re cutting corners in the testing.

No corners have been cut. The candidate vaccines are going through the same phases of trials that any other vaccines have gone through. These trials are subjected to the same peer-review and published in the same journals that other new vaccines and medications are published in. The trial of the Pfizer vaccine involved more than 40,000 participants and was published in the New England Journal of Medicine. The speed to market wasn’t accomplished by skimping on the research. It was accomplished by starting the manufacturing of doses while the trials were still going on. Operation Warp Speed guaranteed purchase of hundreds of millions of doses of candidate vaccines, so that the manufacturers could start working immediately. That way, as soon as the vaccine is approved, lots of doses are already available.

Does the vaccine work?

Yes. The Pfizer vaccine involves two doses given 21 days apart. (Different vaccines might have different dose schedules.) In the randomized trial, the vaccine was 95% effective in preventing COVID-19.

I’m worried about side effects. Is it safe?

It’s very safe. In tens of thousands of doses there were no serious side effects. The most common side effects are pain, swelling and redness in the arm, and fatigue, headache and chills. The informal hubbub from my doctor friends who have already received the first dose is that it’s much less side-effecty than Shingrix, the vaccine that prevents shingles. There was a single report of a mild allergic reaction, so everyone will be watched for 15 minutes after administration to monitor for that. I’m scheduled to get my first dose on Thursday. I wouldn’t do it if I didn’t think it was safe.

Will I grow a third eye?

That hasn’t been reported yet. However, that would be very cool. Having two eyes gives you depth perception, so, if I’m doing my math right, a third eye should let you see in the fourth dimension.

Where do I get it? Will your office give it out like the flu shot?

Unfortunately, the Pfizer vaccine has very complex storage, distribution and reporting logistics. Because of that, it’s being distributed primarily through large medical centers. Cedars-Sinai has received tens of thousands of doses and has begun vaccinating healthcare workers and long-term facility residents. Future vaccines by other manufacturers will have different requirements. If any are appropriate for distribution in a small doctors’ office, we’ll definitely ask to get some.

Do I have to get the vaccine?

No. COVID vaccination will be completely voluntary, but you should get it, both to protect you and those around you.

When can I get the first shot?

The goal is to vaccinate everyone who wants to be vaccinated by the middle of 2021. So you’ll get it in the next six months. Since that many doses are not available now, local and national health authorities are making priority lists of groups of patients. The details of those lists are not yet known, but it’s assumed that older and sicker patients will be prioritized.

As soon as I know that doses are available to the general public, I’ll email all my patients with all the information I have. I know many of you are very eager to get the first dose ASAP. I’m eager to help you do that. We just don’t know anything yet.

I’m a 107-year-old essential worker. Can I get the vaccine before everyone else? I don’t want the hoi polloi getting it before me.

Everyone who wants to be vaccinated will be vaccinated. I’m not the one making up the priority list of which groups get the vaccine first. Even if a future vaccine is distributed through our office, it will be done according to recommendations from the LA County Dept of Health and the CDC. We’ll give it in whatever order they say. Please stop calling me to remind me how important you are. I love all of you the same. This is a race against time, not a race against your neighbor. We’re all going to get there.

I know this holiday season will be disappointing for many of us. But the end is in sight. Please help keep the ICUs less full by staying out of other peoples’ homes and avoiding gathering with people who don’t live with you. I know that we’re bored and lonely and frustrated. But we just need to keep our most vulnerable loved ones from getting infected for a few more months.

In the midst of all this loss, we might forget what has been achieved. A novel virus made the leap to infecting humans in December 2019. Within one year of that event, multiple safe and effective vaccines have been developed. That is an extraordinary scientific, technical and logistical accomplishment. Distributing it to hundreds of millions of people will be another one.

I hope your Hannukah was bright. I hope your Christmas is merry. I wish all of you a much much better New Year.

Learn more:
Frequently Asked Questions about COVID-19 Vaccination (Centers for Disease Control and Prevention)
Information about the Pfizer-BioNTech COVID-19 Vaccine (Centers for Disease Control and Prevention)
Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine (New England Journal of Medicine, by subscription)

What’s happening now?

In LA County, COVID-19 cases, deaths, and hospitalizations have been steadily declining for the last two months. Hospitalizations and deaths from COVID-19 in LA are at lows not seen since the early months of the pandemic. This contrasts with a recent increase in cases nationally, including in cities like New York. Whether this new resurgence of cases will spill into Los Angeles remains to be seen.

What can we do to keep the numbers here improving? Continuing to do what we’re doing is clearly working, but with many suffering from “pandemic fatigue”, I thought it might be helpful to review how COVID-19 spreads so we can focus our efforts on what works.

How is COVID-19 transmitted?

A very useful review of what we know about COVID-19 transmission was published in the Annals of Internal Medicine two weeks ago. The review stressed that this virus is transmitted through respiration, that is through someone inhaling a particle recently exhaled by someone else. Physical proximity and ventilation are major determinants of transmission risk. That’s why many clusters of transmission happen in crowds, and most clusters of transmission happen inside. So physical distancing helps reduce risk, and gathering outside rather than inside helps reduce risk. Studies also suggest that wearing a mask, both in health care settings and in general, decreases the risk of transmission.

A poorly known but important conclusion of this review is that transmission of COVID through contact of surfaces not been conclusively documented. When the pandemic began, since we didn’t know how the virus was transmitted, many people took it on themselves to disinfect packages, clean doorknobs in their house, and generally treat all surfaces as if laden with cooties. After studying many transmission clusters over all the months of the pandemic, we can confidently conclude that the virus isn’t usually spread that way.

In July, The Atlantic published an interesting article reviewing the “hygiene theater” (decontamination for good PR, rather than for health) that developed during the pandemic even as it became clear that surfaces were not a threat. It also made the good point that resources devoted to disinfecting surfaces (for example on subways) are depleting resources better devoted elsewhere (for example, by letting subway cars run for more hours instead of being cleaned daily). I’m hoping that alleviating anxieties about this issue will conserve our physical and emotional energy to concentrate on what works in the coming months – physical distance, ventilation, masks.

So as a gift to yourself, please stop cleaning your packages, stop Windexing your produce, and lose the gloves. Handing someone a credit card, touching an elevator button, or opening a door might transmit Staph or lots of other germs, but it’s unlikely to transmit the novel coronavirus. It’s OK to use your bank teller’s pen to sign something. (But, according to my local branch, it’s not OK to absentmindedly insert it into one’s nose. Another reason to wear a mask.)

Yes, between patient visits we’re still meticulously cleaning surfaces in our examination rooms. But that’s because (1) we have low enough patient traffic to do the extra work, (2) we are intentionally being more cautious than necessary, and (3) we want to reassure patients who are simply frightened, regardless of the data. That is, we don’t only want patients to be safe; we also want them to feel safe.

A personal note

With Yom Kippur hours away, I wanted to acknowledge what an awful year many of us are having. Some of my patients have lost thriving businesses. Many of us had healthy habits which were carefully constructed over years to keep us physically and mentally fit. These habits toppled overnight, and are hard to recreate. Many of us miss seeing our grandkids or our parents in person. We are more isolated, more frightened, and less optimistic than we’ve ever been. None of us are at our best.

So for all the times I was cranky when I should have been calm, for all the times I spoke when I should have listened, for all the times I tried to explain how you should think before understanding how you feel, for all the times I was short when I should have been patient, I sincerely apologize. Please forgive me. I’m confident there are better days ahead. We must remember that in life (unlike math) truth is frequently self-contradictory. We are all doing the best we can; we can all do better.

Learn more:

LA County Daily COVID-19 Data (LA County Dept of Public Health)
Transmission of SARS-CoV-2: A Review of Viral, Host, and Environmental Factors (Annals of Internal Medicine)
Hygiene Theater Is a Huge Waste of Time (The Atlantic, July 27)

Monday, April 27, 2020

“Example is the school of mankind, and they will learn at no other.”
— Edmund Burke

If you’re reading this, I assume you’ve already been recruited into one of the several armed motorcycle gangs that scours the city’s ruins for canned food. I know finding a generator to recharge your laptop isn’t easy so I’ll keep this short.

Oh, wait. That’s the first paragraph of the post I’m writing for June. Where’s my end of April post? Oh, here. Let’s start over.

In Los Angeles we seem to have achieved a stalemate with the virus. The number of new daily cases and the number of new daily deaths aren’t going up exponentially, but they’re not going down exponentially either. Both graphs are bouncing around in the same range. Hospital censuses are also neither exploding nor decaying like any well-behaved exponential function should. Hospital beds, ICU beds and ventilators remain available to those who need them. That, in itself, is a major achievement. The curve is flattened, which after all was the first goal of our response.

Now our collective minds are obsessed with two questions. What’s the next step? And how does this nightmare eventually end?

Let’s consider the second question first. What does the final goal look like? We’re currently pinning our hopes on the development of a vaccine or on acquiring herd immunity.

There will certainly be lots of resources, brains, and time devoted to finding a vaccine for the novel coronavirus. But vaccines for coronaviruses are notoriously difficult to develop. The SARS outbreak of 2002 was caused by a coronavirus and led to a search for a vaccine. There still isn’t one. But that outbreak was tiny compared to the current pandemic. Surely, the global search for an effective vaccine will be successful this time. Well, I hope so. But if you need an example of a virus for which a search for a vaccine consumed many dollars and many minds for many years and remains unsuccessful, look no further than HIV.

And what about herd immunity? Herd immunity is the mechanism by which many immune individuals (the herd) protect the other vulnerable individuals from infection. They do so by simply providing the virus fewer vulnerable hosts. If a high enough fraction of the population is immune so that, on average, each infected person infects fewer than one vulnerable person, then the epidemic fizzles out. The goal is similar to the goal of social distancing – put fewer vulnerable people next to infected people – but instead of distance we use immune people as the barrier.

No one is sure how many of us need to be immune for that to happen. 30% is the lowest estimate. Other experts say 50 to 60%. Are we close to that? A study by USC and the LA County Dept of Public Health tested a random sample of LA County residents for antibodies to the novel coronavirus. It found that about 4% of us have the antibody. This was touted as good news since it’s 20 times greater than the number of cases diagnosed through the viral swabs. That implies that the fatality rate of the virus is 20 times lower than we thought, and it underscores that many cases have such mild symptoms they never seek medical attention. A similar study in Santa Clara County found an antibody prevalence of about 3%. Neither of these studies has been peer-reviewed, so there may be flaws in their methodologies or calculations that have yet to come to light. But as far as we can tell now, with the possible exception of New York, there is no reason to believe that any US city is close to achieving herd immunity.

Our office now offers a Covid-19 antibody test (performed by Quest Diagnostic Labs). I will offer it to my patients, but as I explained in my last post, the test will be more useful as a broad measure of community antibody prevalence than to help any individual patient make any decision.

So the novel coronavirus might end up being contained through social distancing and herd immunity and other traditional public health measures, as SARS was contained in 2003. Or it might be eradicated through a massive vaccination program as smallpox was. But these outcomes will not happen soon, certainly not in the next year. Or, like common colds, the novel coronavirus may mutate and continue to circulate globally and evade our grasp.

This tremendous uncertainty about the final goal must inform how we approach the first question. What next?

The LA County “safer-at-home” order has been extended until May 15. Different localities, faced with different numbers of cases, different economic pressures, and different healthcare capacities are making different decisions about when and how to allow people to reopen businesses. The debate about whether to “reopen the economy” has generated much heat but little light. The debate presupposes that it was the government that shut down the economy. It wasn’t. It was the customers. Customers stopped going to restaurants before the stay-at-home orders were given in most states. And they will likely stay away long after the restrictions are lifted. There is no valve labeled “Economy” that someone in Sacramento or Washington can turn to get everyone back to work.

Economies will restart in fits and starts from the bottom up, with every state, city, and family making decisions and balancing risks in a way that fits their particular circumstances. Some states are lifting restrictions now, and some are not. Some colleges have pledged to return to on-campus instruction in the fall, and some will continue online instruction in the fall. And that’s as it should be. There is no reason to expect, say, an older successful urban couple to make the same decision as a twenty-something poor rural couple. The first couple has much to lose by being exposed to coronavirus and little to lose by isolating at home. The second couple might have no alternative but to return to work. And the probability of infection and the consequences of infection would be much lower for them.

This embrace of radical localism will require all of us to reject the extreme arguments on both sides of the debate. On one extreme are those who assert that economic matters are irrelevant and that the shutdown should last until a vaccine or some effective treatment is found. They assert that when lives are at stake, no economic toll is too great. The biggest flaw with this position (and there are many others) is that making everyone poorer will make more people die of other things. Poor people die of chronic illnesses at a much higher rate than rich people. That’s because patients with chronic illnesses frequently benefit from expensive new medications, lifestyle modifications, and logistical support that consume a lot of resources. So if we make everyone poorer by keeping businesses shuttered we’re not simply trading dollars for lives. At some point we’re trading future lives lost to diabetes, heart disease, stroke, and depression for lives saved now from coronavirus.

Those on the opposite extreme assert that the novel coronavirus is no worse than a bad flu, that our reaction to it is exaggerated, and that any further economic toll is unjustified given the tiny death rates in the majority of the country. The biggest flaw with this position (and there are many others) is that the economic toll has been largely dealt by customers, not governments. In a city in which cases and deaths are climbing and hospitals are overwhelmed, very few people will go to movie theaters regardless of whether the economy is officially “reopened”. What may persuade them to go to movie theaters is declining case counts and available ventilators. So managing the pandemic is a prerequisite of, not a competing priority to, reopening the economy.

Given that our understanding of the novel coronavirus is in its infancy, and given that our projections of the consequences of various actions are based entirely on mathematical models that may be entirely unreliable, we should approach local experimentation with some humility. Rather than heap scorn on localities that try a different approach, let’s study their data and learn from their experience. No one knows how to keep the ICUs from filling up while letting people try to make a living. So let’s stop pretending we know.

The best we can hope for is to muddle through, learn from each other, keep a close eye on the local daily case counts, and apparently hoard toilet paper and canned food. Which reminds me. If an armed motorcycle gang comes to your door to recruit you, don’t try to impress them with your unicorn henna tattoo.

Learn more:
More L.A. County Residents Likely Infected With Coronavirus Than Thought, Study Finds (Wall Street Journal)
USC-LA County Study: Early Results of Antibody Testing Suggest Number of COVID-19 Infections Far Exceeds Number of Confirmed Cases in Los Angeles County (LA County Dept of Public Health)
COVID-19 Antibody Seroprevalence in Santa Clara County, California (medRxiv)
Reopening Has Begun. No One Is Sure What Happens Next. (New York Times)
Do Lockdowns Save Many Lives? In Most Places, the Data Say No (Wall Street Journal opinion)
Governor Newsom Outlines Six Critical Indicators the State will Consider Before Modifying the Stay-at-Home Order and Other COVID-19 Interventions (Office of Governor)

My previous posts about the novel coronavirus:
Testing, Testing Part 2
Of Masks And Meaningful Measures
Updates From The Socially Distant
Testing, Testing
Novel Coronavirus FAQ Part 2 – Pandemic Hullabaloo
Coronavirus Frequently Asked Questions
Community Transmission Of Novel Coronavirus In LA County
What You Need To Know About The Novel Coronavirus

 

Can you feel it, now that spring has come?
That it’s time to live in the scattered sun.

Waiting for the sun. Waiting for the sun.
Waiting for the sun. Waiting for the sun.

This is the strangest life I’ve ever known.
— Waiting for the Sun, The Doors

[I’m writing this on Friday, April 17. Everything in this post might be false in a few days, and conditions might be different in places other than Los Angeles. Keep up to date by checking your local health department website.]

So far, Los Angeles has been fortunate. Hospital censuses are stable. Hospital beds and ventilators continue to be available to those who need them. We have not (yet) seen the numbers of deaths and levels of suffering endured in New York. In a county of 10 million, we have counted just over 11,000 cases and just under 500 deaths. The number of new daily cases hasn’t been increasing. We’ve flattened the curve. Today, for the first time, the number of deaths is less than the day before. Things might be on the verge of improving, so we habituate to the danger and grow restless. Our kids (especially the extroverts) complain that they want to visit friends. Parents stare at the calendar and wonder if they can make tentative summer vacation plans. All of us have become children in the back seat on an interminable road trip. “Are we there yet?”

As a possible roadmap out of eternal isolation our nation turns its lonely eyes to testing. In this post I summarize the current status of testing for Covid-19 and what we can expected in the short-term.

Testing for virus

Tests for the novel coronavirus have become more widely available. In LA County over 67,000 individuals have been tested. This test checks for the actual presence of viral particles on a swab, which is collected from the patient’s nose or mouth. This is used to determine if the patient is currently infected with the virus that causes Covid-19.

The City of Los Angeles is offering free drive-through testing to anyone with any symptoms consistent with Covid-19. The tests are performed only by appointment, which can be scheduled on the website. Doctor’s offices, including ours, also have tests. So if you don’t feel well, call your doctor or make an appointment for drive-through testing through LA City.

The main drawback of these tests remains their sensitivity of about 70%, which I discussed in my last post about testing. It means that 3 out of 10 patients with Covid will test negative. So, while positive results are very reliable, negative results are not.

Antibody testing

Antibody tests (also called serology tests) are blood tests which detect antibodies produced by the patient’s immune system in response to infection. It’s important to note that an antibody test can not be used to diagnose or exclude a current Covid infection. That’s because antibodies can take several days to appear after the onset of illness. A negative test may simply mean that the patient has Covid but hasn’t made antibodies yet. A positive test may mean that she had Covid weeks ago and has recovered.

We have tests for antibodies to lots of other viruses, like HIV and herpes and measles. Unfortunately, antibody tests for the novel coronavirus are not yet ready for prime time. A few private labs have marketed tests to patients that have very poor validation. The problem with these tests is high false positive rates. That means that the test may give a positive result if the patient has antibodies to some old coronavirus strain that she contracted years ago when she had a mild cold. More reliable tests are being developed but are not yet available. Cedars-Sinai is one of the many medical centers working on a serology test, and we will offer it in our office as soon as we can. But that’s still at least a few weeks away.

So the anticipation for a reliable antibody test runs high, for several reasons. First, we know that many cases of Covid-19 are very mild and those patients don’t seek medical attention. This has led many to speculate that there may be a huge population of people who’ve already had the disease, recovered, and are now immune. They could conceivably get back to work, take the lead in patient care, and stop social distancing. They could also provide the frequently mentioned but infrequently understood herd immunity, by which the vulnerable are protected by being surrounded by people who are immune.

The second reason people are looking forward to an antibody test is that a lot of us (including yours truly) went through a miserable flu-like illness in January or February. It’s very tempting to hope that we had Covid-19. After all, even though cases of Covid weren’t officially discovered in Los Angeles until later, given the amount of travel between LA and China, and given what we know about asymptomatic spread of Covid, couldn’t community transmission have been happening in LA much earlier? If some of us have already recovered from Covid, then presumably we are immune, with all the potential resultant benefits I already listed above.

The problem with these lines of thinking is the problem with all wishful thinking. We tend to overestimate the likelihood of positive outcomes and we tend to underestimate the outcomes we’d rather not have to consider. It would be great if half the population was already immune and it would be great if I already paid my dues when I was sick in January. But that doesn’t make it so.

We have very few ways to estimate the prevalence of mild Covid in the population so far. A letter to the New England Journal of Medicine published the results of Covid testing for every woman admitted to the labor and delivery ward of a New York City hospital from March 22 to April 4. 15% of the women tested positive, even though only 2% had symptoms. That means in the US city with the greatest concentration of Covid cases, about 15% were actively infected as of two weeks ago. Mathematical models suggest that 29 to 74% of us would have to be immune to confer herd immunity on the rest of the population, that is to give the virus so few available vulnerable hosts that the epidemic fizzles out. That suggests that in all but the hardest hit cities, herd immunity will remain out of reach. The whole point of flattening the curve has been to minimize new cases and keep the numbers as low as possible. Success has meant keeping the demand for beds and ventilators less than the supply. But it has also meant that there are very few of us who are immune.

There are lots and lots of other viruses that I might have had when I was sick in January, including adenovirus, parainfluenza, respiratory syncytial virus, and metapneumovirus (which is the most fun to say). Even though I had the flu shot, I could have also had influenza. I don’t want to have had those other viruses. I desperately want to have had Covid so I could be bulletproof now, but that doesn’t make it so.

I will certainly encourage all my patients to have the antibody test when it’s available, and I’ll definitely have it myself. But we should understand what to expect (and what not to expect) from it. A negative result will definitively exclude a prior infection, but will not exclude a current infection. A positive result will diagnose a past infection with a certainty that depends on the specificity of the test and the prevalence of past infection in the population. (The specificity of any test is the fraction of people who don’t have the disease who test negative.)

Imagine if 1% of the people in LA County have had Covid and are immune. That’s 100,000 people, which is about 9 times the number of people who have had a positive virus test so far. Say a test with 99% specificity is developed. That means for every 100 people who don’t have antibodies who are tested, only one false positive results. So for every 100 people tested you would have 1 true positive (the person who actually had it), 1 false positive, and 98 true negatives. That means that half of the positive results would be false. That would make a positive result not very useful. The only way to decrease the fraction of positive results that are false would be to use it in a community with higher disease prevalence or to have an even more accurate test.

So a positive test might mean you’ve had Covid before, or maybe not. That wouldn’t give you the certainty you need to stop social distancing and potentially expose yourself to the virus.

The serology test attempts to answer a different question for individual patients and for entire populations. An individual patient is asking “Am I immune now? When I was sick last month, was that Covid?” To those questions the test might give a definitive no or a maybe. It’s unlikely that we’ll have a test reliable enough to get a trustworthy yes. But populations ask “What fraction of us have already recovered from Covid?” And if lots of people get tested, that’s a question that we might be able to answer.

But that answer might be disappointing. We might find out that we’re not there yet. We might find out that our herd is not immune. We might find out that this horrible trip doesn’t end until we have a vaccine. Until then, stay inside and stay healthy.

At the beginning of a pestilence and when it ends, there’s always a propensity for rhetoric. In the first case, habits have not yet been lost; in the second, they’re returning. It is in the thick of a calamity that one gets hardened to the truth–in other words, to silence. So let’s wait.
— The Plague, Albert Camus

Learn more:
COVID-19: The Worst Days of Our Careers (Annals of Internal Medicine)
Schedule a COVID-19 Test (City of Los Angeles)
Antibody Tests For Coronavirus Can Miss The Mark (NPR Shots)
Health Authorities Roll Out New Coronavirus Tests to Gauge Infection’s Spread (Wall Street Journal)
Prominent scientists have bad news for the White House about coronavirus antibody tests (CNN health)
Coronavirus ‘Immunity Passport’ Stumbles in U.K. (Wall Street Journal)
Universal Screening for SARS-CoV-2 in Women Admitted for Delivery (New England Journal of Medicine)

My previous posts about the novel coronavirus:
Of Masks And Meaningful Measures
Updates From The Socially Distant
Testing, Testing
Novel Coronavirus FAQ Part 2 – Pandemic Hullabaloo
Coronavirus Frequently Asked Questions
Community Transmission Of Novel Coronavirus In LA County
What You Need To Know About The Novel Coronavirus