Mass Fever Screening FAQs
No, fever screening systems cannot identify what virus the person is carrying. How fever screening systems can help is to identify higher risk hyperthermic individuals for processing. Elevated temperature is the first ‘visible’ sign of an unhealthy/sick person, therefore they belong to higher risk group that may require processing.
No, fever screening systems are capable of picking up hyperthermic individuals with high probability of having a fever. Skin temperature gives good indication if the subject is hyperthermic but not absolute core body temperature readout. Many research and clinical trials even when performed in ideal conditions, have shown that skin temperature has very poor correlation to actual core body temperature. Therefore one should not attempt to determine core body temperature from skin temperature.
Many ‘fever screening systems’ on the market are nothing more than modified/rebadged/repackaged industrial thermal cameras. One of the standard functions on such industrial systems are ‘hot spot tracking’ and is conveniently activated as standard option. They will track the hottest spot on the screen (not necessarily human). However, there are no scientific relevance to this feature. In fact, when referred to clinical trials, research papers and real life experiences, these readings are highly misleading. All our systems, including the latest Sentry MK3 do not display subject’s core body temperature. We do however have an input which an operator can setup minimum screening threshold by indicating targeted core body temperature (e.g. mild fever @37.6degC to high fever at 38degC). Our systems will then automatically perform necessary system offsets and calibration to target individuals in that temperature group.
According to best practice recommended in SS 582 : Part 2 : 2013. (ICS 11.040.55). “SPECIFICATION FOR. Thermal imagers for human temperature screening: Implementation guidelines”, secondary screening using clinical temperature measurement method is required. In most cases, core body temperature will be determined by a ear thermometer.
A mass fever screening system is able to filter out only higher risk individuals for secondary screening. Therefore, instead of using ear thermometer on thousands of subjects (something quite impossible), crew only need to process a small faction of traffic picked up by screening systems.
Yes, fever screening systems only detect persons displaying febrile symptom. If an EBOLA carrier is not displaying any symptom, the system cannot pick him up.
Trials and field experiences have shown that properly implemented mass fever screening operations consistently pick up higher number of febrile individuals vs self-declare method.
Not necessary. These are common confusion among users (and salesmen alike). Temperature resolution only indicates how many decimal points the camera can display and sensitivity (NETD) figure really just provide a theoretical detector noise level. What is relevant for human screening is ACCURACY. In most reputable industrial based systems, you will find accuracy stated in specification as “+/- 2degC or 2%, whichever is higher”. At 37~38 degC range, +/-2 degC applies. Considering core body temperature difference between healthy and a high fever subject is 1 degC, such systems are clearly not suitable.
Acquiring proper hardware is a good start, however, an effective screening program requires formulation and implementing correct workflow and training of crew. In most cases, our experiences have shown this is most difficult as most organisation have limited knowledge in this specialised area thus identifying and working with a good partner can be beneficial.
If you have further questions with regards to screening equipment and implementation guidelines, please feel free to contact us.