It seems so natural. You arrive at work during COVID-19. You have your temperature checked on the way in the door. You learn that you don’t have a fever, and you move forward with greater confidence that you don’t have COVID-19.
Except it isn’t true. The evidence to date does not support temperature checks as an effective strategy for identifying carriers of COVID-19. There are many ways in which temperature checks and other in-person health exams can introduce additional risk into the workplace for both employers and employees.
And yet we haven’t put our thermometers away.
Temperature checks for COVID-19 are security theater.
COVID-19 is not the most lethal or infectious virus — not by a long shot. Its biggest asset is its sneakiness.
For many viruses, individuals are at their peak of infectiousness when they are symptomatic. This is not so for SARS-CoV-2. On average, infected individuals are contagious for days prior to the onset of symptoms, infectiousness peaks just prior to and around the time of onset, and infectiousness declines quickly in the days following the onset of symptoms. Some individuals infected with SARS-CoV-2 remain asymptomatic for longer periods of time, and these asymptomatic carriers have viral loads similar to symptomatic carriers, suggesting that they are just as likely to spread the virus.
The onset of a detectable symptom such as fever is a lagging and inconsistent indicator of COVID-19 at best, which makes it ineffective for the proactive task of managing viral spread. Even as symptoms go, multiple studies have demonstrated that fever is far from the most reliable indicator of COVID-19.
Mild fevers are challenging symptoms to measure. Studies that have found strong connections between fever and SARS-CoV-2 infection have typically used a very narrow criteria for what qualifies as a fever — a change as little as a single degree Fahrenheit . This is well within the normal range for temperature variation across individuals due to differences in baseline body temperature, environments, activities, or unrelated biological events.
Fever is also a noisy indicator of COVID-19; it is a symptom that is commonly associated with many health conditions. There are other symptoms which are more reliably associated with COVID-19 and less common. Start with anosmia, which is a detectable change to an individual’s sense of taste or smell. This is often among the first symptoms that individuals notice and several diagnostics are being developed for screening.
So why are we still checking temperatures?
All of us are desperate for answers and certainty, which are in short supply right now. Temperature checks are an easy and familiar ritual in which to take comfort. They sound and look like something that should be effective. They feel reassuring.
There is also some history at work here. There were two other outbreaks of coronaviruses in the last twenty years: Severe Acute Respiratory Syndrome (SARS, or SARS-CoV-1) in 2003 and Middle East Respiratory Syndrome (MERS) in 2012. There is ample evidence that fever was a more reliable indicator of disease for both SARS and MERS. Scanning for fever, when combined with contact tracing and quarantine, was an effective strategy for managing the spread of SARS and MERS within a few months.
In the early stages of the COVID-19 pandemic, when we had little else to go on, it made sense to generalize from these data. They were the best knowledge we had. We now have enough evidence to know better and yet our behavior hasn’t changed.
Health exams are for a clinician. Health screenings are for work.
There is a big difference between a health screening and a health exam.
Health exams require the assessment of physical symptoms. This should be done by a clinician. A clinician is trained to make a diagnosis, which requires interpreting a symptom like fever alongside other symptoms.
Health screenings are an attestation of an individual’s health. They are an essential part of safe work during COVID-19. Screenings can and should be conducted safely by an employer. And it turns out that, when you take the measurement and assessment of physical symptoms out of the picture, screenings can be done virtually just as well as they can in person.
At Ohia Advisors, we coach teams through their work transitions during COVID-19. This has given us a lot of empathy for how challenging conversations about health and safety are during COVID-19. A lot has changed for employers and employees in a short period of time.
Where employers have the latitude to make their own decisions regarding screening or are required to use health attestations, we strongly advise that they use virtual health screenings instead of in-person health examinations such as temperature checks.
We understand that in some cases local requirements mandate that employers conduct temperature checks. In these cases, we advise employers to be wary of the risks outlined below and to advocate for more evidence-driven regulations as best they can.
In-person health screenings for COVID-19 are a big risk.
It’s not just that screenings can happen virtually — it’s that they really should. In-person health screenings open the door to a whole set of avoidable risks for employers and employees.
- They may endanger employees’ privacy and represent a liability for the employer. As fevers are associated with a wide array of health conditions, a temperature screening will provide employers with data on a broad set of health issues. This opens the door to a range of liability issues for the employer unless they are prepared to help staff manage the full range of health issues that may be present.
- They are a health risk to employees. In-person screenings produce high-traffic areas and can easily result in queues. Both of these are significant risks for the spread of COVID-19 in a workplace and should be avoided whenever possible.
- They are an even bigger health risk to screeners. In-person screenings represent an additional risk to screeners, who are exposed to a broad set of contacts, any of whom might be infectious. The proper use of personal protective equipment and safety protocols can minimize this risk but will not eliminate it.
- They are expensive and time consuming. Health screenings require the purchase of equipment and dedicated time from employees or contractors. These are significant and unnecessary expenses for employers. This is a case where the right decision is also the most cost-effective one.
- They are an opportunity for bias. In-person screenings introduce an opportunity for bias that is wholly avoidable. Any aspect of an individual’s appearance can influence what questions are asked and how they are asked. It is challenging to minimize bias across in-person health screenings. Clinicians receive training and work hard to accomplish this. In the absence of planning and training, it is virtually impossible. Virtual health screenings do not eliminate the potential for bias, but they lead to far fewer opportunities for inconsistency among individuals.
Put the thermometers away.
We are all learning as we go when it comes to managing life with COVID-19. We hope that temperature checks and in-person health exams in the workplace become relics of our early experience navigating the pandemic. There is no evidence that either can be effective in minimizing the spread of the virus. There are much cheaper and more effective ways for employers to safeguard the health of their employees during COVID-19.