Remember the bird flu? Avian influenza (H5N1) was first discovered in birds in 1996, with the first human crossover detected in 1997. Since then it has been discovered in 50 countries and is endemic in six. If you are old enough to remember, there was a bit of a bird flu panic back in the late 90s. Fortunately, so far, those fears have not been realized. But it’s important to remember that the bird flu is still around. Even more important is to remember that there are thousands of potentially pandemic viruses in the world.

Avian influenza adapted to infect birds, and mostly spreads through poultry. Bird to human transmission (zoonotic infection) is rare, and usually occurs in those who work in the poultry industry with long term exposure. The virus is very deadly, with a case fatality rate of about 60%. Worldwide there are 700 reported human cases. However, the virus does not spread easily from human to human. Such transmission is very rare, and is not sustainable. This is why the virus has not caused an outbreak or worse among humans. There are also other strains of flu virus that primarily infect birds, such as H10N5. We now have the first report of an H10N5 infection in a human, in a poultry worker in China. Contact tracing did not reveal any other cases.

For now we have experienced rare bird to human zoonotic transmission of flu strains primarily adapted to birds (colloquially “bird flu”) without any significant or sustainable human to human spread. So what’s the concern? As was originally raised by in the 90s, the concern is that every time a virus jumps from an animal reservoir to a human there is the potential that it will either mutate or will combine with another virus to cause a new strain that is highly contagious to humans. It happens, as we are now experiencing with the SARS-CoV-2 virus. So what do we do about it?

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We know a lot more now about SARS-CoV-2 and COVID-19 than we did a year ago when this pandemic was just getting into full swing. One of the big questions was about the emergence of new variants – how fast does the virus mutate, and what is the probability of variants with new properties emerging? Scientists have been tracking the variants since the beginning. It’s actually a good way to track the spread of the virus, and our ability to sequence the genome of specific viruses is fairly advanced.

As of August 2020 scientists had identified six strains or variants of SARS-CoV-2, without any significant difference in biological function among them. This was encouraging – the hope was that this virus mutates slowly and that no functionally new versions would emerge. This is important for two reasons. The first is the question of whether or not someone who has already suffered COVID-19 or been infected without symptoms could become reinfected. This is partly about the strength of the immune response to infection, but also about whether or not new strains would be able to bypass immunity to older strains.

However, by the beginning of 2021 two things were happening, one good, one bad. Vaccine distribution was ramping up. Several vaccines were approved toward the end of 2020 and while initial distribution was slow, it is speeding up. By now almost 59 million Americans have received at least one dose of a vaccine, and we are being promised availability for everyone who wants a vaccine by May. At the same time daily new cases of COVID are dropping fast, although still relatively high compared to the Spring and Summer of 2020.

But the bad news is that three new variants of SARS-CoV-2 have now been identified that are functionally different – one identified in the UK, one in South Africa, and one in Brazil. These variants have several mutations affecting the structure of the spike protein that gives coronavirus its name, and is responsible for its ability to infect cells. Spike proteins are also a target of antibodies produced by infection or vaccine. As news about these variants comes dripping it, it’s not good. All three appear to be more infectious. They spread more easily than the older variants, which means more robust protection might be necessary to prevent spread. Further, because of their increased infectivity, they are rapidly becoming the dominant strains where they spread.

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This was inevitable. We are in the midst of a massive rollout of two new vaccines for COVID-19. Anxiety and fatigue levels from the pandemic are already running high, and there is a pre-existing anti-vaccine movement who is sure to exploit this. But perhaps most significantly, we are now living in a post-social media world. Information, even medical or scientific information, may get to the public unfiltered, ripe to be misinterpreted by people who do not understand the relevant science. Such is the case with a “viral” video showing a woman who claims her symptoms are a side effect of the Moderna vaccine (short answer – they almost certainly are not).

Messaging is critical to the success of public health measures. Normally information about possible side effects from a drug or vaccine would be filtered through medical experts. When millions of people are involved there is going to be a lot of noise. Coincidence alone would result in many negative outcomes occurring by chance alone shortly after getting a vaccine. Epidemiologists need to look for patterns in the data that indicate there is likely to be an actual causal relationship to the vaccine. It helps if there is also a plausible mechanism. This system has captured vaccine side effects in the past, so you cannot reasonably argue that the system is rigged not to find such associations. The swine flu vaccine in the 1970s caused cases of Guillaine Barre Syndrome. A specific flu vaccine (Pandemrix – no longer on the market) likely caused cases of narcolepsy in 2009. So if any of the current COVID vaccines have a similar side effect, we will catch it.

Reporting scary anecdotes that have not been scientifically evaluated to the public is not a good idea. This is likely to misinform rather than inform, and will have a death toll attached to it. But with social media there is no way to stop this from happening, so we just have to do damage control when it does.

As a side note, I have to point out that I usually refrain from commenting on a specific individual’s medical condition in public. This is to respect the privacy of those individuals, and also because if I have not personally examined them and taken their history, commenting is inappropriate. But medical science communicators can comment about topics relevant to a public case or issue. I can speak generally about the relevant topics. There is also an exception when a private person puts their own medical history into the public domain, especially if they also use that history to make recommendations to the public, and doubly so if those recommendations are false and harmful. They have surrendered any expectation of privacy and they have made their own personal history relevant to the discussion about a public health issue. That is the case here.

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How many people have died in the US so far from the COVID-19 pandemic? It depends on how you count the numbers. The official count of US COVID-19 deaths is 214,000. This number is often reported as “at least” this amount, because this is a compilation of all deaths where COVID-19 was officially listed as a cause of death. Experts recognize that this is likely to be a gross underestimation, because people may die from the disease at home without ever being diagnosed.

In any such system, regardless of how careful you are, there are going to be false positives and false negatives. When it comes to the cause of death there are very specific coding guidelines. COVID-19 must have directly lead to the death of the individual. Laboratory confirmation is strongly encouraged, but doctors may code COVID-19 as a probable cause of, in their clinical judgement, the patient had COVID-19 and it fits the epidemiology, even if they did not get a test. When COVID-19 is severe enough to kill, it is a fairly recognizable clinical condition. This does open the door to other fatal viral respiratory infections to be coded as COVID, but these instances are likely to be rare.

States report their data differently. Some only report confirmed cases. Some report confirmed and probable. Some states get their numbers from death certificates, while others count deaths among diagnosed cases of COVID-19. Taking all of this into consideration, COVID-19 deaths are likely to be underestimated in the aggregate rather than overestimated. Some critics argue that allowing “probable” cases overestimates the total deaths from COVID, but if you look at the data state-by-state you will see that probable cases are small in number compared to confirmed. In Arizona, for example, probable cases are only about 5% of the total deaths reports, the vast majority of which are confirmed. So even in the very unlikely scenario that all probable cases are false positives, that only gives a 5% variance (and keep in mind, many states don’t report probable cases at all).

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It’s always disappointing (not surprising, but disappointing) when a purely scientific question unnecessarily becomes a political or social one. Whether or not to wear a face mask during an historic pandemic should be purely a question of risk vs benefit – does it work, and is there any downside? The evidence is clear enough at this point that mask wearing helps reduce the spread of COVID-19. David Gorski recently reviewed the evidence, including a recent meta-analysis, and found:

When it came to masks, an analysis of 29 unadjusted and 10 adjusted studies demonstrated that the use of masks was also associated with a large decrease in transmission, both for N95 masks and for disposable surgical masks or similar reusable 12- to 16-layer cotton masks.

Since that review there have been further studies, such as this one, showing that countries who adopted mask wearing early had fewer cases of illness. The benefit, therefore, seems clear. What’s the downside? Pretty minimal. Sure, it may be a pain and a bit uncomfortable, but this is a minor nuisance at worst. People who are hard of hearing and rely on lip reading probably suffer the biggest downside. There are masks with transparent sections over the mouth to facilitate lip reading, however, for those who need to deal with the hearing impaired.

So wear a mask if you are sick, around other people who are sick, or just in public. In some countries it is considered hygiene etiquette, as it should be.

As a side note, there is some confusion because early on the WHO recommended not to wear a mask in public unless you or others were sick. This was not because the evidence did not support it, however, but because there was a shortage of PPE and people were hording. The idea was to make sure that essential workers had enough masks. This is no longer an issue, and the WHO has revised their recommendations, which are now in line with the CDC – wear a mask, even just to go in public.

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There is pretty clear evidence now that the lockdown worked in “flattening the curve” and reducing cases, hospitalizations, and deaths from COVID-19.  By one estimate the lockdown has already prevented about 60 million cases in the US alone, and about 250,000 additional deaths, perhaps more. This doesn’t even take into consideration what would have happened if the pandemic was allowed to overwhelm hospital systems around the country. In the Northeast, which was hit early and hard, hospital systems were overwhelmed in that they had to reconfigure their resources, and compromise on protocols in order to meet the demand. In some NY hospitals they had two patients on one ventilator. Imagine this, but far worse, and more widespread. How many deaths not directly related to COVID-19 would have resulted from this strain on the system?

So I think we can take fair comfort in the fact that the lockdown, as painful as it is, has at least worked as intended. Many people have raised the question – did the lockdown work also on the flu? If so, why don’t we do some version of the lockdown during the height of flu season? We now have data on the effect of the lockdown on this year’s flu season in the northern hemisphere – it stopped the flu season about 5 weeks earlier than is typical.  It’s possible some of this decrease in numbers is due to fewer people seeking treatment, but it’s likely that it is mostly due to reduced spreading of the flu virus.

This year in the US the flu season was toward the higher end in terms of cases and deaths – not out of the range of typical flu seasons, but at the bad end of the spectrum. In the US there were between 39 and 56 million cases of flu this year, with 24-62 thousand deaths. The upper limit of flu season deaths is around 65 thousand. The reason for the wide estimate range is because most people don’t get tested in order to confirm that their flu-like illness is indeed the flu. So confirmed cases are a small percentage of total cases, which are estimated by clinical presentation. Globally the estimated number of flu deaths each year is 290,000–650,000.  Right now the global number of deaths attributed to COVID-19 is 436,000, but the number of new cases is still on the upswing.

Before you fall prey to the “COVID-19 is just a bad flu season” fallacy, keep in mind that the pandemic is not over yet. And, as stated, this is with lockdown. But, what does this say about how we handle typical flu seasons, and how we will likely handle COVID-19 in the future? Here are some thoughts.

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The question of whether or not wearing a facemask “works” is incredibly complicated. It may not seem so at first, but let me list some of the specific questions contained in that broad question. We need to consider different kinds of masks – cloth, surgical, N95. We need to consider who is wearing the mask – someone known to be infected, someone who is well, and in what setting, out in public or in the presence of those known to be sick. We also need to operationally define “work.” We can measure reduction in the spread of the virus, in droplets, in aerosolized particles, and also in different conditions (breathing, coughing) and at different distances. We can measure deposition of virus on surfaces. We can also measure transmission of actual disease, both the chance of spreading and of catching specific illnesses. And of course, all of these questions need to be addressed with each specific infection, and so prior research may not apply perfectly to COVID-19. And further we need to compare the efficacy of wearing a mask to the real-work effectiveness of intending to use a mask.

It should not be surprising, therefore, that we do not have all the answers to these questions specifically for COVID-19. What we have are slices of research with different results and therefore you can look at the preliminary evidence we do have and come to different conclusions. The CDC and the WHO, in fact, have done this. Here is the CDC recommendation:

“CDC recommends wearing cloth face coverings in public settings where other social distancing measures are difficult to maintain (e.g., grocery stores and pharmacies), especially in areas of significant community-based transmission.

CDC also advises the use of simple cloth face coverings to slow the spread of the virus and help people who may have the virus and do not know it from transmitting it to others.  Cloth face coverings fashioned from household items or made at home from common materials at low cost can be used as an additional, voluntary public health measure.

Cloth face coverings should not be placed on young children under age 2, anyone who has trouble breathing, or is unconscious, incapacitated or otherwise unable to remove the mask without assistance.

The cloth face coverings recommended are not surgical masks or N-95 respirators.  Those are critical supplies that must continue to be reserved for healthcare workers and other medical first responders, as recommended by current CDC guidance.”

And here is the WHO:

If you are healthy, you only need to wear a mask if you are taking care of a person with COVID-19.

The WHO recommends masks for those who are symptomatic or known to have COVID-19, and those exposed to people who are sick, but not for the healthy out in public. The guidelines are actually not that far off from each other, but there is that one difference.

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It’s important to properly calibrate your concern over new potential threats. Fear is an adaptive trait that focuses our attention and energy on avoiding danger. Too little fear, and we walk into avoidable risk; too much, and we waste time and energy without reason, perhaps even causing unnecessary harm. Proper calibration requires an objective, factual, and balanced approach. Keep that in mind when reading stories and fearmongering about the new Wuhan Coronavirus.

First, the genuine concern – this is a legitimate outbreak of a new virus that causes pneumonia and is potentially fatal. This is now the 7th Coronavirus found to infect humans. Four strains cause essentially common cold, a benign upper respiratory infection. Two previously discovered viruses cause more severe illness, the SARS and MERS viruses. SARS (Severe Acute Respiratory Syndrome) started in 2002 in China and over 2003 the epidemic resulted in thousands of cases and 774 confirmed deaths. MERS (Middle Eastern Respiratory Syndrome) first appeared in 2012, in the Arabian Peninsula and has a 30-40% mortality rate. These are serious infections. So it is reasonable to be concerned about the third serious Coronavirus infection. What do we know so far?

The numbers are moving fast, but as of right now there are 4,500 confirmed cases and 106 deaths. All the deaths are in China, there are sporadic cases outside of China (all imported from China) but so far no person-to-person spread outside of China. The virus likely originated from the combination of a bat strain of Coronavirus and an unknown strain, but came to humans through contact with snakes. The infection causes a severe viral pneumonia. Most of the fatalities so far have been elderly, but at least one otherwise young and healthy individual has died from the infection. Infection is spread through water droplets (sneezing and coughing). It is still unclear, with conflicting reports, whether or not the virus is contagious before symptoms present (which would be bad) but the CDC is currently denying this.

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This is going to be a long struggle, perhaps endless. Antivaxxers have been around since there have been vaccines, for over two hundred years, so there is no reason to expect they are going anywhere. Rather, we need an equally permanent anti-antivaxxer movement (otherwise known as the skeptical movement).

After the Disneyland measles outbreak, there has been political pressure to push back against antivaxxers and strengthen our vaccine requirements. This resulted, for example, in SB277 in California, a law to remove personal beliefs as a reason for vaccine exemption. The return of measles in the last few years (1,282 cases in 2019 in the US, more than 140,000 worldwide) has fueled similar push back. But the antivaxxers have not taken this lying down. They are now fired up to defend their debunked conspiracy theories and pseudoscience at the expense of public health.

A recent clash in New Jersey shows the intensity on both sides. Bill S2173 narrowly failed in the senate amid vocal protests by the antivaxxers. The bill would have removed religious exemptions for vaccine requirements for schools and daycare. In order to save the bill, proponents amended it to apply only to public schools, but this only cost more support as some senators correctly pointed out this will only concentrate the unvaccinated in private schools and result in more outbreaks. Proponents of the bill vow to revise it and try again.

It’s clear that there is now intensity on both sides. One side, however, is completely wrong, something I rarely say but there are issues where this is clearly true. Antivaxxers claim, falsely, that vaccines don’t work, they cause more harm than good, they are linked to autism and other serious complications, and even that there is a corporate-government conspiracy to hide these facts. Debunking these claims will take many many articles, but fortunately I and my colleagues have already written them. You can look through here and also here for articles addressing pretty much every antivaxxer claim. But it is an unfortunate reality that there is always an asymmetry in these cases, because it takes much more time and effort to debunk a false claim than to make it in the first place.

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It’s fun and interesting to look back over the last decade and think about what has happened and how far we have come. Round years are arbitrary, but it’s a sufficient trigger to take stock and hopefully gain some perspective on the medium course of history. There is a lot to say about the 2010s, and I may take the opportunity to say more, but I want to discuss in this essay what is perhaps our greatest challenge and disappointment over the last decade. In many ways this has been a lost decade for climate change mitigation.

Over the last decade the scientific evidence (and resulting consensus) that the planet is warming, that humans are the primary driver of this trend, and that the consequences are not likely to be good, has only become greater. The last five years have been the hottest five years on record, and this has been the case for most of the last decade. The year 2016 was the hottest, because it was an El Niño year (short term fluctuations will still be overlaid on top of the longer term trend) but the trend is unmistakable. The story of the world’s ice is more complex, with greater regional and year-to-year variations, but total global ice has been decreasing, and if anything accelerated over the last decade. The Greenland ice sheet in particular experienced accelerated melting. As a result there is a real and growing scientific consensus, north of 97% among relevant scientists, that anthropogenic climate change is happening.

We are also experiencing more extreme weather events. We are seeing more droughts, fires, heat waves, and more powerful storms. In the last decade it become clear that, while the worst consequences of climate change are decades and even centuries in the future, we are starting to see real consequences now.

Economists have started to weigh in as well. Numerous studies were published over the last decade, concluding that – climate change will cost the world many billions of dollars and will reduce economic growth, costing even more. Further, the option of allowing climate change to happen and adapting to the results will likely be the costliest option. In addition to the monetary cost, there is a quality of life cost. Extreme weather causes displacement, psychological trauma, and social upheaval. If you think we are having a refugee crisis now, just wait as flooding increasing and more locations become essentially uninhabitable.

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