A Direct Observation Video method for Describing COVID-19 Transmission Factors on a Micro-Geographical Scale: Viral Transmission (VT)-scan
ABSTRACT
Background:
The H1N2 Coronovirus, commonly referred to as COVID-19, has devastated economies, education, personal well-being, and many other aspects of human life. Screening, therapeutics, and vaccines are necessary to combat the virus as are preventative measures such as mask wearing and social distancing. While most health agencies agree these basic behaviors reduce the transmission of COVID-19, efforts to improve the assessment of these behaviors are lacking.
Objective:
The aim of this study was to create a direct observation video method [Viral Transmission (VT)-scan] for assessing COVID-19 transmission behaviors and related personal (e.g., weight status) and environmental (e.g., place – crosswalk) factors, examine the reliability of VT-scan and apply VT-scan in a case study.
Methods:
A wearable video device (WVD) was used to obtain videos along a 4.69 mi pre-determined route that coursed through educational, retail/business, and residential areas. Videos were collected on one weekday/wk over a seven-wk period between 11:15 a.m. and 12:19 p.m. Week 1 videos were used to examine the reliability of VT-scan while videos from weeks two to seven were used for the case study. Information on mask wearing, physical distancing, surface/face touching, and personal and environmental factors were was extracted from the videos by trained reviewers according to a set of comprehensive rules.
Results:
At total of 129 and 916 people were described for the pilot and case studies, respectively. All outcomes displayed good to excellent intra- and inter-reliability with ICCs ranging from 0.836 to 0.997. Further, significant (p<0.001) Kappa statistics were found for all outcomes and no differences in geolocations were noted between reviews. In the case study, most people described were 18-30 y of age (72.5%), white (81.1%), and normal weight (80.7%). The majority had a mask (60.8%) but 22.1% of them wore it improperly, 45.4% were not physical distancing, and 27.6% were simultaneously mask and physical distancing non-compliant. Transmission behaviors varied by demographics with white, overweight/obese males least likely to be mask-compliant and white, overweight/obese females least likely to practice physical distancing. Certain environments (e.g. crosswalks) were identified as “hot spots” or areas where higher rates of adverse transmission behaviors occurred.
Conclusions:
This study introduces a reliable method for obtaining objective data on COVID-19 transmission behaviors and related factors. It may be especially useful for describing micro-scale (localized) level data for use in agent-based modeling and policy formation/adjustment.