You visit your hair salon, but before you check in, someone aims a thermometer at your forehead. Go to your primary physician’s office with a belly ache complaint, and you can’t get past the door before a nurse greets you with a “let’s take your temp.” The same holds true for many venues and organizations across the country. As early as April, restaurants remaining open in some states began to require temperature checks before allowing their patrons inside. And early on in the pandemic, the CDC’s website had a temperature log template that households could print out for use at home.
The question is… do these tests actually help screen for COVID-19?
What Are They Checking For?
Thermometers detect elevated body temperatures, the body’s way of saying something is wrong. A higher than normal temperature can be caused by many issues, such as:
- A virus
- A bacterial infection
- Heat exhaustion
- Certain inflammatory conditions such as rheumatoid arthritis — inflammation of the lining of your joints (synovium)
- A malignant (cancerous) tumor
The CDC standard for what defines a fever and that has been adopted by places such as Disney World, is 100.4 degrees Fahrenheit or 38 degrees Celsius. COVID-19 is one of the many diseases that can cause such a fever among people who have symptoms.
Who Is Doing Temperature Checks?
Depending on location, restaurants may require temperature checks before you enter the establishment. Popular destinations enforcing this requirement include New York City, and some eateries in other areas are choosing to take temperatures even without a mandate.
Many employers require their employees to undergo temperature checks, either at home or on-site, as part of a daily health assessment. Some high-profile examples include AMC Theatres, the NFL, and restaurant chains like Olive Garden
Most large entertainment venues are requiring temperature checks before visitors can be admitted as well. Disney World and Universal Studios Orlando have checkpoints in place at the gates, and even smaller regional attractions like Hershey Park, Six Flags, and Busch Gardens are checking visitors for fevers before entry. You can expect similar screenings at sports stadiums. Teams including the Colts, Bills, and Browns have already announced them as part of new safety measures.
Legal requirements come from state and local governments. JD Supra posted a breakdown of statewide orders you can check to see what rules your area has in place.
Do Temperature Checks Work?
A temperature can catch someone with a fever, but not necessarily someone with COVID-19. A study from South Korea showed that asymptomatic people can carry as much virus as symptomatic ones. The CDC recently revised its testing guidelines for international travelers, saying that “symptom-based screening has limited effectiveness because people with COVID-19 may have no symptoms or fever at the time of screening, or only mild symptoms. Transmission of the virus may occur from passengers who have no symptoms or who have not yet developed symptoms of infection.”
Despite that change, the CDC still includes fever as a known symptom of COVID-19 and temperature checks as part of its advice for businesses. The WHO also includes fever among the main symptoms and temperature checks in its recommendations for the workplace.
As for actually taking temperatures, even Anthony Fauci, MD, director of the National Institute of Allergy and Infectious Diseases, is skeptical. In a recent NIAID video, Dr. Fauci was asked if there was use in taking temperatures on everyone going into a hospital. His answer? “This is going to disappoint a lot of people by saying this, but the answer is no. The benefit is marginal. We have found at the NIH that it is much, much better to just question people when they come in.”
He expressed concern, based on his own experiences, that on-site temperature checks tend to be inaccurate especially during summer months. Whether self-reporting temperatures can be trusted, however, is dependent on the situation. The interview did not touch on how effective self-reporting would be when dealing with the general public rather than medical professionals.
The Take Home
While it cannot account for asymptomatic carriers, temperature screening is still one of the most common practices in use in an attempt to limit the spread of COVID-19. Passing a temperature check does NOT mean that you or anyone else are not infected. Even after passing a temperature screening, the rest of the CDC’s guidelines such as wearing a mask, frequent handwashing, and limiting contact with others should be observed to prevent the spread of the disease.