Turn on the TV news, or look at a news website, and you'll see charts, graphics, and dashboards that supposedly indicate the latest with COVID-19 – statistics revealing the number of tests, cases, hospitalizations and deaths, along with where they happened and whether they are rising or falling.
Different stories are told depending on the dashboard. But one thing is certain: These indicators lag behind the actions we take, or don't take, on COVID-19. As researchers who focus on public health, we can tell you that a fully accurate, real-time snapshot of the progress of the virus isn't possible.
Some don't get tested
There are many reasons for this. Here's one: diagnostic testing data are incomplete. Someone infected with COVID-19 must first come in contact with the virus either through the air or (less likely) environmental surfaces.
Symptoms show between two and 14 days later. But at least 40% of those infected will never manifest symptoms, or show such mild ones they don't even suspect they have COVID-19. So they may never get tested, which means they won't show up in the total number of tests, or the total number of cases.
Another example: because of the lack of testing availability – a widespread problem in the U.S. since the start of the pandemic – not everyone who should be tested gets a test.
And another: the tests themselves are not perfect. Up to one-third who get a negative result may actually be infected. This happens because they are tested before they have a viral load sufficient enough for detection. Or maybe the sampling is not adequate. Or perhaps the test itself simply failed.
Case numbers don't tell the full story
This is why problems arise when we use case numbers to determine disease levels in a community. Case counts actually reflect what was happening in a community weeks earlier. Four weeks, for instance, could elapse between the time a person is exposed to the virus and when they are reported as a case.
Even the best testing results often take a week to report to public health authorities, and longer to appear on dashboards. Some testing results, seriously delayed, may take ten days or more.
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Other factors impact the metrics. Laboratory results, often released in batches, may introduce artificial variation in case numbers. Someone who tested two days ago, then got a result back immediately, might be added on the same day as someone who was sick two weeks ago, but whose test results were delayed.
To smooth out these variations, it helps to look at a rolling seven-day case average.
Hospitalization is a clearer metric for assessing the level of community disease. Those who are seriously ill, in most cases, will be hospitalized whether previously tested or not. Data suggests roughly one in five infected persons are hospitalized.
Individuals seem to do okay for the first week, with more life-threatening symptoms showing in the second. That means hospitalizations represent exposures that happened three or four weeks earlier.
Again, a seven-day rolling average evens out artificial variations. There is one caveat for this: Though hospitalization is a useful metric, only about 20% of infected people need it. That means hospitalization numbers alone underestimate the number of people infected and what age groups they represent.
States vary on cause of death
The death numbers are not a reliable indicator either. In some states, to count as a COVID-19 death, the deceased must have had a test reporting positive. In other states, probable cases are reported.
As clinicians learn how to better treat COVID-19, fatality rates are dropping. Deaths, the longest lagging indicator, reflect people who were infected six or eight weeks earlier. When comparing one region to another, deaths are best expressed as rates – a ratio of deaths to population.
Another issue: News reports do not always clearly distinguish between diagnostic testing, which shows if you currently have COVID-19, and antibody testing, which shows if you had it in the past, and now harbor antibodies that can fight it.
So far, however, antibody testing has not provided a useful picture of who has been infected and who has not. Once that happens, it could provide researchers and clinicians with some indicators on how widely the virus has spread.
Though the dashboards are ubiquitous on television, none of these frequently used indicators they feature is perfect. Still, taken together, they provide a reasonable approximation of COVID-19 transmission in communities. But as authorities make decisions, they should take into account the numbers are weeks old.
What does this mean to you? Understanding these limitations may help you understand your risk. We are still in the midst of a pandemic that is not under control. Being educated will help all of us from becoming a part of tomorrow's lagging indicators.
This article was originally published by The Conversation and written by Pamela M. Aaltonen and Catherine Lynne Troisi. You can read it here.
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Why do some folks use social media but don't engage?
Psychologist says people who never comment on social media share these 5 positive traits
For over 20 years, social media has developed into a staple in many people’s day-to-day lives. Whether it’s to keep in communication with friends and family, following the thoughts of celebrities, or watching cat videos while sipping your morning coffee, there seem to be two types of social media users: commenters and lurkers.
The term “lurker” sounds equally mysterious and insidious, with some social media users writing them off as non-participants at best or voyeurs at worst. However, mindfulness expert Lachlan Brown believes these non-commenters have some very psychologically positive and healthy traits. Let’s take a look at how each one of these traits could be beneficial and see how fruitful lurking might be even though it can drive content creators crazy.
1. Cautious about vulnerability
Consciously or not, making a post online or commenting on one puts you and your words out there. It’s a statement that everyone can see, even if it’s as simple as clicking “like.” Doing so opens yourself up to judgment, with all the good, bad, and potential misinterpretation that comes with it. Non-commenters would rather not open themselves up to that.
These silent users are connected to a concept of self-protection by simply not engaging. By just scrolling past posts or just reading/watching them without commentary, they’re preventing themselves from any downsides of sharing an opinion such as rejection, misunderstanding, or embarrassment. They also have more control on how much of themselves they’re willing to reveal to the general public, and tend to be more open face-to-face or during one-on-one/one-on-few private chats or DMs. This can be seen as a healthy boundary and prevents unnecessary exposure.
Considering many comment sections, especially involving political topics, are meant to stir negative emotional responses to increase engagement, being extra mindful about where, when, and what you comment might not be a bad idea. They might not even take the engagement bait at all. Or if they see a friend of theirs post something vulnerable, they feel more motivated to engage with them personally one-on-one rather than use social media to publicly check in on them.
2. Analytical and reflective mindset
How many times have you gone onto Reddit, YouTube, or any other site and just skimmed past comments that are just different versions of “yes, and,” “no, but,” or “yes, but”? Or the ever insightful, formerly popular comment “First!” in a thread? These silent browsers lean against adding to such noise unless they have some valid and thoughtful contribution (if they bother to comment period).
These non-posters are likely wired on reflective thinking rather than their initial intuition. Not to say that all those who comment aren’t thoughtful, but many tend to react quickly and comment based on their initial feelings rather than absorbing the information, thinking it over, researching or testing their belief, and then posting it. For "lurkers," it could by their very nature to just do all of that and not post it at all, or share their thoughts and findings privately with a friend. All in all, it’s a preference of substance over speed.
3. High sense of self-awareness
Carried over from the first two listed traits, these silent social media users incorporate their concern over their vulnerability and their reflective mindset into digital self-awareness. They know what triggers responses out of them and what causes them to engage in impulsive behavior. It could be that they have engaged with a troll in the past and felt foolish. Or that they just felt sad after a post or got into an unnecessary argument that impacted them offline. By knowing themselves and seeing what’s being discussed, they choose to weigh their words carefully or just not participate at all. It’s a form of self-preservation through restraint.
4. Prefer to observe rather than perform
Some folks treat social media as information, entertainment, or a mix of both, and commenting can feel like they’re yelling at the TV, clapping alone in a movie theater when the credits roll, or yelling “That’s not true!” to a news anchor that will never hear them. But contrary to that, social media is a place where those yells, claps, and accusations can be seen and get a response. By its design, social media is considered by experts and the media as performative, regardless of whether it is positive or negative. Taking all of the previously mentioned traits into account, one can see why they would prefer to “observe the play” rather than get up on the stage of Facebook or X.
On top of that, these non-commenters could be using social media differently than those who choose to fully engage with it. Using this type of navigation, there may be nothing for them to comment about. Some commenters are even vying for this for their mental health. There are articles about how to better curate your social media feeds and manipulate algorithms to create a better social media experience to avoid unnecessary conflict or mentally tiring debate.
If you go on a blocking spree on all of your accounts and just follow the posters that boost you, it could turn your social media into a nice part of your routine as you mainly engage with others face-to-face or privately. In terms of commenting, if your curated Instagram is just following cute dogs and all you have to offer for a comment is “cute dog,” you might just enjoy the picture and then move on with your day rather than join in the noise. These non-commenters aren’t in the show and they’re fine with it.
5. Less motivated by social validation
The last trait that Brown showcases is that social media users who browse without posting tend to be independent from external validation, at least online. Social media is built to grow through feedback loops such as awarding likes, shares, and reposts of your content along with notifications letting you know that a new person follows you or wants to connect. This can lead many people to connect their activity on social media with their sense of self worth, especially with adolescents who are still figuring out their place in the world and have still-developing brains.
Engaging in social media via likes, shares, comments, and posts rewards our brains by having them release dopamine, which makes us feel good and can easily become addictive. For whatever reason, non-commenters don’t rely on social media as a means to gauge their social capital or self worth. This doesn’t make them better than those who do. While some non-commenters could have healthier ways to boost their self worth or release dopamine into their systems, many get that validation from equally unhealthy sources offline. That said, many non-commenters’ silence could be a display of independence and self confidence.
Whether you frequently comment online or don’t, it’s good to understand why you do or don’t. Analyzing your habits can help you determine whether your online engagement is healthy, or needs to be tweaked. With that information, you can then create a healthy social media experience that works for you.