Temperature Screening Is Ineffective, Says US, UK, Canada, Israel, And Ireland Health Leaders
Health leaders around the world are increasingly speaking out about the problems of using temperature screening. IPVM has verified statements from the US, UK, Canada, Israel, and Ireland health leaders.
This comes while temperature / 'fever' camera vendors are making huge profits selling these systems, setting up a contest between health officials and many of the largest video surveillance industry players.
In this post, we examine recent statements from these health officials, the scientific evidence for fever screening, the technical challenges faced by fever screening products, and what this could all mean for sellers:
- US Fauci Says Temperature Products "Notoriously Inaccurate"
- UK Government Warns "Unreliable", "Do Not Work"
- Ireland Health Authority Also Skeptical
- Canada & Israel Health Officials Say "Not Effective", "Inefficient"
- Thermal Cameras Often Inaccurate
- CDC Does Not Recommend Fever Screening for Reopening
- Fever Screening Misses Asymptomatic and Presymptomatic
- Australian Hospitals Find Fever Screening Has "Negligible Value"
- Legal Implications For Sellers
US Fauci Says Temperature Products "Notoriously Inaccurate"
On August 14, the NIH's National Institute of Allergy and Infectious Diseases posted an interview between Dr. Anthony Fauci and Lieutenant Colonel Jason Blaylock, chief of medicine at Walter Reed Army Medical Center.
During the interview, Dr. Fauci criticized temperature screening as "notoriously inaccurate" and said the White House and NIH had abandoned it:
The remarks are transcribed below:
[Col. Blaylock]: Has there been any demonstrated utility that you're aware of to capturing COVID-19 infection coming in the doors of hospitals by actually taking temperatures?
[Dr. Fauci]: You know, Colonel, 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 and save the time because the temperatures are notoriously inaccurate many times. So at the NIH Clinical Center across the street from you guys, and at the White House where I go in every day, we've abandoned entry of a determination of temperature for the following reason: It’s the middle of the summer, we’ve had like what - 15 days 90 degrees in a row? So I went into the White House the other day, my temperature was like 103 until I got into the air conditioned car and it was 97.4. When I tried to get into another facility, my temperature was 93, which means I should’ve been on a respirator! So I think we’ve got to just abandon that and say let’s just be prudent, ask questions, and do it that way.
[Col. Blaylock]: Again I think that sounds incredibly reasonable Dr Fauci and we kind of had the same thoughts over Walter Reed as well so it’s very reassuring to hear you echo that as well.
The NIH is the US' primary government public health research organization with a budget of over $34 billion last year; Dr. Fauci serves as the director of the NIH's National Institute of Allergy and Infectious Diseases and is a longtime presidential advisor on infectious diseases.
Canada: "Not Effective At All"
the more you actually understand this virus, the more you begin to know the temperature taking is not effective at all [...] If we have a significant number of asymptomatic or pre-symptomatic people, that also even reduces the effectiveness even more.
The video of Canada's Chief Public Health Officer making this statement is embedded below:
UK Government Warns "Unreliable", "Do Not Work"
Last month, the UK government's top medicines and medical device authority, the MHRA, announced that "temperature screening systems" are "unreliable" and there is "little scientific evidence" to support their use:
Temperature readings from temperature screening systems will measure skin temperature rather than core body temperature. In either case, natural fluctuations in temperature can occur among healthy individuals. These readings are therefore an unreliable measure for detection of COVID-19 or other diseases which may cause fever
There is little scientific evidence to support temperature screening as a reliable method for detection of COVID-19 or other febrile illness, especially if used as the main method of testing [emphasis added]
The MHRA announcement quoted Health Minister Lord Bethell warning businesses that "temperature screening tools" simply "do not work":
As pubs and restaurants begin to reopen, it’s important businesses do not rely on temperature screening tools and other products which do not work
The best way to protect customers and minimise the risk of catching the virus is to always follow social distancing guidelines, wearing a face mask on public transport and enclosed public spaces, and regularly washing your hands [emphasis added]
Ireland Health Authority: "Not Found To Be Effective"
Ireland's Health Information and Quality Authority, which monitors health standards compliance, found earlier this month (based on a review of prior studies on airport screening) that "mass screening" using "infrared thermal scanners" was "not found to be effective":
Mass screening programmes using non-contact devices (for example, infrared thermal scanners) were not found to be effective in identifying infectious individuals and limiting spread of disease. Detection rates were consistently low across studies [emphasis added]
The HIQA study noted these systems are sensitive to "confounders" that change people's temperature (e.g. sun, snow) thus "reducing the accuracy":
factors that alter (increase or decrease) temperature act as confounders, reducing the accuracy of screening
HIQA's Deputy Chief Executive Dr. Máirín Ryan stated the "high cost" of such solutions wasn't worth the "very low" detection rates:
the evidence clearly shows that this type of test is likely to be ineffective in limiting the spread of COVID-19. Thermal screening is noted to be high cost and resource intensive. Detection rates are very low due to large proportion of cases that have no symptoms, are infectious before showing any symptoms or who do not present with fever [emphasis added]