Greg Lathan

When news was released in January that Wuhan, China was impacted by the coronavirus, EI immediately launched a series of weekly educational blogs highlighting specific occupational health (OH) and industrial hygiene (IH) measures aimed at infection prevention, which inhibit coronavirus transmission. As a result, our client base has responded with numerous requests for EI’s OH and IH services, specifically targeted at pathogen control within the workplace. As early as mid-February, EI began amassing significant “boots on the ground” experience, aimed at minimizing the occupational transmission of COVID-19. This experience has included PPE training, respirator medical clearance/fit testing, assessment of indoor air quality/building HVAC systems, disinfection and most importantly, medical screening of the workforce for manufacturing, pharma/biopharma, power generation and commercial banking clients. Our COVID-19 blog series captures the most recent technical data from a myriad of reputable sources, which focuses on the mode of transmission of the coronavirus and measures to effectively prevent the occupational spread of COVID-19 as employees return to work.

EI’s next two blog entries will focus on the major points garnered from our field experience during screening of 120,000 employees to identify potential COVID-19 carriers as they reported to work at numerous manufacturing/pharma/biopharma facilities over the past 6 months. During the COVID-19 screening process, in an effort to minimize potential COVID-19 transmission in the workplace, EI employed the New Rochelle Incident Command model for coronavirus testing, where employee body temperature and a standardized COVID-19 questionnaire was administered from their vehicles as employees arrived to work. COVID-19 screening of employees through their driver’s window also added a significant measure of protection between EI professionals who performed COVID-19 screening and the employees screened. This article will compare employee infrared forehead temperature screening data to employee responses compiled from our COVID-19 screening questionnaire in an effort to ascertain which tool was most effective in identifying potential coronavirus carriers.

Part 1: Body Temperature Plays a Secondary Role in Occupational COVID-19 Screening

Infrared Forehead Temperature Screening
All employees with initial thermal scans exceeding 100.4 degrees were confirmed with subsequent infrared thermal scans, followed by an external skin measurement (again taken from the subject’s forehead) with a contact skin thermometer. Most EI clients elected to use the CDC’s 100.4 degree body temperature as the threshold to identify potential employees who were potential COVID-19 carriers. Approximately 0.02% of all employees monitored, or only 2 of every 10,000 employees, exhibited body temperatures of 100.4 degrees or higher.

Given the low forehead temperature readings, measured by EI screening technicians with infrared scanning thermometers (typically ranging between 96.5 – 98.0 degrees), EI took several confirmatory temperature measurements on all employees who exceeded 99.0 degrees as a precautionary measure. ONLY 1.65% of ALL employees monitored exceeded 99.0 degrees. Employees exceeding 99.0 degrees were also asked more detailed questions about potential contact with coronavirus carriers outside of work and any specifics on symptoms they may have failed to disclose during administration of the COVID-19 questionnaire. As a result, closer scrutiny and follow-up of those employees with a body temperature of 99.0 degree threshold (in lieu of a 100.4 degree threshold) DOUBLED the number of employees prohibited from work increased from 2 in 10,000 to 4 in 10,000!

Responses to COVID Employee Screening Questionnaire
Employee responses to the COVID screening questionnaire played a much more significant role in identifying potential COVID-19 carriers than those workers exhibiting a threshold body temperature exceeding 100.4 degrees. As the COVID-19 screening process became more routine, allowing EI screening technicians and employees to become more personally familiar with each other, dialogue with the workforce during administration of the COVID-19 questionnaire became more open and relaxed. Weeks into the process, employees increasingly seemed more comfortable in revealing any subtle symptoms associated with coronavirus infection, including mild headache, loss of taste/smell, gastrointestinal issues, dry/sore throat or minor cough. In addition, employees were also more willing to provide detailed information about their personal activities outside of work (especially following weekend activities which exposed them to crowded gatherings), as well as the health of other members of their family. This personal dialogue yielded details about potential symptoms and lifestyle which could have been easily be missed during simple “yes/no” replies to the COVID questionnaire. 0.3%, or 3 in 1000 employees were prohibited from working based on replies to the COVID -19 questionnaire. A further breakdown of questionnaire results clearly revealed that employees who reported “close contact with a COVID-19 carrier” comprised the majority (slightly over 70%) of those prohibited from work. Only 25% of employees prohibited from reporting to work due to questionnaire replies were based on their admission of being symptomatic.

Statistics from EI’s occupational COVID-19 screening operations of nearly 120,000 employees over the past 6 months clearly demonstrates that a body temperature threshold of 100.4 degrees plays only a secondary role in identifying potential coronavirus carriers, when compared to those identified due to replies to the COVID-19 questionnaire. COVID-19 screening via questionnaire identified over 13 times the number of employees who were potential COVID-19 carriers, than those who exhibited body temperatures greater than 100.4 degrees! Using a lower threshold of 99.0 degrees, coupled with enhanced screening, identified twice as many potential COVID-19 carriers than those using current CDC guidelines. Developing a rapport with the workforce significantly enhances dialogue between the technical staff responsible for COVID-19 screening, allowing the COVID-19 questionnaire screening process to be much more effective at identifying employees who are symptomatic or have had potential contact with a COVID-19 carrier. Until a rapid and cost-effective COVID-19 test becomes readily available, occupational COVID-19 screening operations should focus on close scrutiny and personal interaction with employees during administration of a COVID-19 questionnaire, aimed at identifying potential symptomatic carriers or those employees who may have had contact with a coronavirus carrier.

Next week, EI’s blog will focus on the many key aspects derived from our learning experience during EI’s COVID-19 occupational screening of manufacturing, pharmaceutical and biopharmaceutical facilities over the past 6 months. 

If you have any questions regarding employee medical screening or other COVID-19 related professional services, please contact us at 800.717.3472 or [email protected].