Noncontact Sensing of Contagion

Abstract

The World Health Organization (WHO) has declared COVID-19 a pandemic. We review and reduce the clinical literature on diagnosis of COVID-19 through symptoms that might be remotely detected as of early May 2020. Vital signs associated with respiratory distress and fever, coughing, and visible infections have been reported. Fever screening by temperature monitoring is currently popular. However, improved noncontact detection is sought. Vital signs including heart rate and respiratory rate are affected by the condition. Cough, fatigue, and visible infections are also reported as common symptoms. There are non-contact methods for measuring vital signs remotely that have been shown to have acceptable accuracy, reliability, and practicality in some settings. Each has its pros and cons and may perform well in some challenges but be inadequate in others. Our review shows that visible spectrum and thermal spectrum cameras offer the best options for truly noncontact sensing of those studied to date, thermal cameras due to their potential to measure all likely symptoms on a single camera, especially temperature, and video cameras due to their availability, cost, adaptability, and compatibility. Substantial supply chain disruptions during the pandemic and the widespread nature of the problem means that cost-effectiveness and availability are important considerations.

Keywords: COVID-19; remote sensor; thermal camera imaging; video camera imaging; vital signs.

Figure 1

Thermal image captured by thermal camera.

Figure 2

The non-contact body temperature measurement framework proposed in [41].

Figure 3

The thermal camera-based continuous body temperature measurement framework proposed in [44].

Figure 4

Block diagram of fever screening process proposed in [46].

Figure 5

Block diagram of the cardiac pulse measurement proposed in [53].

Figure 6

Block diagram for the BR estimation proposed in [58,59].

Figure 7

Block diagram of HR estimation proposed in [59].

Figure 8

Schematic of experimental set up used in [61] to monitor BR of neonates using IR thermal camera. (1) Radiant warmer bed, (2) bedside monitor, (3) camera field of view (FOV), (4) IR thermal camera, (5) analysis workstation, and (6) infant under NIRT imaging.

Figure 9

Sample cross-modality images of three domains from the Tufts Face Database [89]. (a) Visible light, (b) thermal, and (c) near infrared (NIR).

Figure 10

The thermal image presented in [98]. The face area is detected using a face detection algorithm and a point on the forehead (red color “+” mark) is selected for temperature measurement. Image courtesy of een.com.

Figure 11

Airports are testing thermal cameras and other technology to screen travelers for COVID-19. (a) The thermal screening setup at Incheon International Airport [102], (b) a similar setup at Canberra international airport [103], and (c) thermal camera setup in public transport [105].

Figure 12

Different sensors used as a video camera. (a) Webcam, (b) digital camera, (c) smart phone, (d) Microsoft Kinect, and (e) UAV.

Figure 13

Block diagram of non-contact HR monitoring system proposed in [116].

Figure 14

Block diagram of noncontact HR monitoring system proposed in [125].

Figure 15

Block diagram of non-contact vital sign monitoring system proposed in [127].

Figure 16

Video recorded by the UAV (3DR solo drone) [145].

Figure 17

Scenarios for remote optical detection of vital signs [146].

Figure 18

Block diagram of non-contact vital sign monitoring system proposed in [146].

Figure 19

Cough detection using drones. Image courtesy of Draganfly Innovations Inc.