After Dogs Detecting COVID-19, What’s Next?

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You may recall my recent post describing studies that demonstrate how accurately dogs can sniff out COVID-19. The answer to “What’s Next?” may be found on your wrist right now.

“Wearables” outfitted with artificial intelligence (AI) to report back health data may send a message to asymptomatic or presymptomatic people with the virus before they spread the disease. That means Fitbits, smartwatches, and heart rate monitors that cardiac patients strap to their wrists may help us fight against those dreaded spikes we’re seeing nationwide. The key is that these wristlets monitor heart rate.

In a fascinating discussion, Abraham Verghese, MD, Professor and Vice Chair in Theory and Practice of Medicine at Stanford in California, spoke with Eric J. Topol, MD, Professor of Genomics at The Scripps Research Institute in La Jolla, California. Topol is also the editor-in-chief of Medscape, which carried the video and transcript of their interview.

First, a couple of items that may seem surprising. You know how diligently everyone’s taking your temperature as a precaution? I’ve visited two doctors, my dentist, and my hairdresser over the past several weeks; each time, my temperature was dutifully taken before I’d stepped well into the reception area.

“But that’s so silly,” said Topol, “because…multiple prospective studies about fever and COVID-19 have found that large numbers of people don’t have a fever.”

Topol mentioned a large study published in Nature Medicine that found only 30% of COVID-19 patients had a fever. Another recent study, published by Color genomics, put that figure even lower: 12%.

So temperature taking may catch some potential COVID-19 infections, but not that many. However, it’s such a noninvasive and seemingly inexpensive method that it seemed to me worthwhile. Unless, of course, it’s causing a distraction, and that appears to be Topol’s objection.

Wth those study findings in mind,  consider that between 30% and 40% of COVID-19 patients are asymptomatic but are still shedding virus—and that presymptomatic people are also shedding virus and are as infectious, possibly even more infectious, than those with symptoms.

For these reasons, Topol calls temperature taking “a placebo.”

Verghese agrees.

“We learned too late that we didn’t emphasize masks enough and we overemphasized temperature measurements.”

Lest anyone be thinking, “Oh, these scientists; they don’t know what they’re doing,” I want to underscore here—because science and scientists are under such unjustifiable and dangerous fire now—that both men agreed the progress that’s been made with the coronavirus has been remarkable.

Said Topol:

“The science is moving at a pace that I’ve never seen—everything, from the structural biology of the virus and the antibodies to the virus from patient, to the design of drugs and vaccines and neutralizing antibodies. The sequence of tracing it temporally and spatially geographically through the world has been extraordinary.”

The point is that this is a very complex virus causing a worldwide pandemic. Equally important, scientific progress isn’t linear: there are bound to be erroneous assumptions, initial errors, blind alleys, and failed medication/vaccine clinical trials.

It’s always been that way. Many of us just haven’t followed the process so closely because we’ve never been in a pandemic before—in which there’s such pressure to move quickly and get things right (and in the US, I must add, ignorant political interference that has had lethal effect).

Topol did discuss testing problems, including the false negatives, the logistics of testing done appropriately to scale, and the expense and time limitation of all these one-time tests. He looks forward to home testing but believes that’s at least several months from now. (See also The New York Times for this article about better testing.)

The big question remains:

“How can we find people in a cluster or an emerging outbreak before it spreads more? Because we know, by the famous Pareto rule or principle, that 80% of transmission comes from 20% of the cases.”

Since we can’t test everyone constantly, the urgency is to locate and concentrate on those “early spreaders.” And that’s where the wearables show promise.

Apparently, such wearables had been generating great interest even before the pandemic, but are now attracting the attention of large research consortiums because of their potential to forewarn about infection with this tricky and highly contagious virus.

Acknowledging that the US is far behind most countries in controlling the spread, Topol said:

“Here is the opportunity to use sensors that get continuous data and would give us an edge.”

In a project named DETECT, begun in March, he and colleagues now have roughly 38,000 participants using a smartwatch or fitness band. Other studies are using rings.

In the first 30,000 people, they found changes in three indicators: increased resting heart rate, more sleep, and fewer steps. And all three indicators then correlated with symptoms and positive tests.

Topol’s group had previously used sensor technology in studying a flu-like illness. When their findings were published in January, a group in Germany developed a smartwatch app that’s being worn by more than 500,000 people; in China, 1.3 million are using such an app.

Verghese, impressed by the number of people involved in Topol’s study, asked two questions: have the results been rigorously tested?; and “do we get the signal early enough to make a difference in some way?”

Topol said they still have to validate the results, but in their Fitbit flu-like illness study, they saw the signal well before the CDC had even observed the presence of the illness. COVID-19 is even more suited to the technology, he believes, because of the large numbers of asymptomatic people.

Studies of asymptomatic people who were on the Diamond Princess cruise ship and in Korea found more than half of them showed the same lung abnormalities as people who’d had symptoms. The presumption is that their heart rates would have shown what they did not feel.

Amazingly, more than 100 million people in the US are currently wearing some kind of wrist sensor to monitor their heart rates. Twenty percent of Americans wear a fitness tracker, according to a Pew Research poll done in January.

I sense that if this approach is validated, it might escape the politicization we’re currently seeing over wearing masks!  Think that’s possible? Of course, it wouldn’t replace masks, but it might be acceptable to some of the diehard anti-maskers among us.

Topol points out that the measure isn’t as helpful on the individual level as it is in a neighborhood.

“If your heart rate goes up, you still don’t know why. But if COVID-19 is in your neighborhood, if there is a cluster, then that makes it more of a real signal.”

Then what? Suppose your Fitbit is yelling at you (digitally)—what do you do next? That’s when testing, tracing, isolation come in, says Topol—while we await more accurate home tests that could provide quick results.

As to the wearable alerts, he says:

“The issue is to get people to be citizen scientists….a lot of people like to get their data and like to get a notification that something in their neighborhood is showing a potential signal, without inducing anxiety. But I’d like to at least raise awareness. You don’t need everyone in the country to be a citizen scientist; you just need enough. We have every state covered but not densely enough yet, so that will be important.”

Verghese raised an important question about equity and access. Not everyone has a Fitbit, smartwatch, or heart rate monitor.

“How do we ensure that we truly are studying a representative cross-section of this country and that everyone has equal access to what is basically a public health issue?”

Acknowledging the gravity of the question, especially in terms of the statistics showing the far greater burden of the pandemic on minorities, Topol stressed that not everyone needs a device: if enough people in the area are alerted to a problem, “The people who don’t have this technology will still derive the benefit of knowing that there’s an outbreak potential in their area.”

I would hope that with this knowledge, there would be a concerted effort to ensure that sufficient numbers of wearables were available in areas most likely to see disease clusters.

But that’s not enough. Topol pointed out:

“The problem is that people in these underrepresented minorities and of lower socioeconomic status don’t have access to testing. They aren’t looked after. Many of them are afraid to come in because they could be deported, or who knows what could happen to them. We have a lot of collateral damage from the pandemic here because of our tenuous and, in many cases pathetic, framework of healthcare.”

It is deeply troubling that we continually confront the vast numbers of people, particularly poor and minorities, who are being deprived of decent health care in our still wealthy nation. But I was pleased to see that the question was at least asked and discussed in this conversation. I’ll be looking at additional ways healthcare has been inequitably skewed in the near future.

My questions for you: Do you currently wear a Fitbit, smartwatch, or heart rate monitor? If you do, would you like to have it inform you if you have possible COVID-19 symptoms? If you don’t wear one, would you be willing to for this purpose? And any other comments you’d care to add are, as always, most welcome!


20 thoughts on “After Dogs Detecting COVID-19, What’s Next?

  1. Interesting post, Annie. I have a Fitbit, mainly for convenience as I recharge by plugging into my computer rather than searching for batteries when it stops. I hate it when it keeps telling me to get off my backside and do something. We have a portable blood pressure machine and heart monitor at home, not on a watch. What would be the added cost of adding COVID-19 detector to a watch? Most of these smartwatches are too expensive for a lot of people. The costs don’t seem to be coming down….perhaps they will in the future.

    Liked by 1 person

    1. Thanks, Len. If you’re using your Fitbit regularly, then it could be useful based on the three indicators Topol cites from their previous study of a flu-like illness: increased heart rate, fewer steps, and less sleep. But that wouldn’t suggest you have the disease; it would simply be an indicator that you’d benefit from being tested.


  2. I’d be worried about false positives on a smart device. The best thing to do is get tested if you feel you have been exposed. The company I work for has started mandatory testing this month for everyone. I think Im okay but its best to be sure.

    Liked by 1 person

    1. I understand your concern, but the point is simply that the indicators suggest that a person get tested, which is what you’re advocating anyway. I’m glad your company is providing testing, but many people still don’t have such access. Plus, as you know, there has been a problem with false negatives and long waits between testing and results, which both leave asymptomatic people spreading the virus. And a person can test negative one week and be exposed the following week, so that also doesn’t prevent the spread. For all these reasons, I think these wearables may be a promising addition to the disease-fighting toolbox.


  3. I wear an Apple Watch and I do use it to keep track of my daily steps and I periodically check my resting heart rate. I charge it at night, so it doesn’t keep track of my sleep patterns. As to your specific question, sure, I would you like to have it inform me if I have possible COVID-19 symptoms? It sure beats going to the local COVID-19 testing center and having that long Q-tip-like thing shoved up my nose!


    1. That’s good. But the point is if a person (I won’t say “you”) gets substantial changes in those indicators, that person may want to then get tested—and hopefully with a non-nasal swab-type test!

      Liked by 1 person

      1. I don’t know how I missed this Annie, maybe when I was sick in June, but it was a good read. I’ve watched a tv special about how quick they are to learn detection of a certain smell. I’ve had two COVID tests (in June, both negative as I expected but I had a fever so I went anyway), and believe me I’d much rather have a friendly sniff from a dog than the painful nasal swab!


  4. Very interesting essay. So, changes in heart rate, sleep and physical activity might indicate that a person is infected. I imagine that this is a development that will get more and more traction and attention.


  5. I think I would, Annie, although there would inevitably be concerns about how the data would be used/who by etc. It would be a huge cache of personal information being managed and kept. I know the hoops that I have to jump through ethically before I collect any data for research – how long I will keep data for, who has access to it in, for what purpose it can be repackaged, what would happen to the information once there is an effective vaccine etc. An interesting topic of research.


  6. That’s an excellent point, Matthew; we should all be more vigilant about uses of our personal data.
    In the discussion I explored, Verghese did ask Topol about privacy concerns. Topol’s response was simply that the matter is taken care of by informed consent. I felt that response didn’t really tell us anything, so I omitted their exchange from my post.
    Thanks for raising the issue!


  7. Mmm definitely an interesting one! I was very unsure about the sniffer dog concept, even though some believe it’s possible for animals to detect illnesses, like the dogs that can sniff out cancer. With wearables, I think they’re looking typically at those ‘common’ symptoms that unfortunately in this case aren’t always guaranteed among the infected. They could look for spikes in temperature that don’t happen, or racing heart beats that don’t happen. When I had suspected coronavirus, again without being 100% sure as there was no testing available to me back then in the UK, I didn’t have the raging fever or continuous cough. I did get incredibly loud heart beats, fast heart rate (that a fitbit like device might just think is me running around – I wish!), a strange sort of sore throat, and worsened breathing difficulties. That said, if a device could pick out even a few cases, that might be better than nothing. The other issue is again with all things digital that these devices aren’t foolproof, they can fail and they can be subject to privacy concerns and hacks. I think as the population becomes increasingly concerned about privacy and protection of their data, they’ll be less willing to subject themselves to such monitoring.

    Caz xx


    1. Hi, Caz. Thanks for your very thoughtful response. In this study, they are not looking at fever, which the investigator points out is not nearly as often present as expected. They are looking at heart rate, increased sleep, and fewer steps, so it would be a pattern over a brief period of time, not solely relying on one indicator. Their previous work using sensors has been validated and is in extensive use.
      As to the important issue of privacy, I get the sense people are less concerned, rather than more so—as they give away so much personal information about themselves. I’m not saying that’s a good thing; It just seems to be what’s happening.
      Always good to hear from you. Take good care.
      Annie xx


  8. An interesting idea. I know that many people track their BP at home and that many simple BP sensors also measure heart rate – this might weave it’s way more deeply into older, less affluent communities. I would think that sleep quality and low activity/fatigue might be the easiest to notice subjectively, so with heart rate data alone it would be better than nothing.

    I do not own a tracker myself but maybe this would be a good reason to get one.

    Liked by 1 person

  9. This is hopeful. I don’t own any of those devices and wonder how the normal ups and downs of life would affect the data. Stressed? Exhausted? Hot? But not sick? What could it hurt, I guess, to track it all and see what we learn.


  10. I think they look for considerable changes in normal patterns. And it’s not intended to be diagnostic: it’s designed as a pretest to see areas that might be hot spots.


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