With over 200,000 fatalities and unemployment rate highest since the Great Depression, COVID-19 has a profound impact on the United States. Failure to effectively test and shortage of Personal Protective Equipment (PPE) in March 2020, when COVID 19 was at its infancy in the US, proved detrimental to the nation. This failure is attributed to:
- Slowness of regulatory bodies: Even many weeks into the response, there was still no diagnostic or surveillance test available outside of the Center for Disease Control for most of our member laboratories. Moreover, private hospitals wanting to create tests of their own were subject to a Food and Drug Administration process called an “emergency use authorization.” This added further complications.
- Testing shortage: Widespread shortages of test kits, specimen collection materials, PPE and reagents. Delay in retrieving testing results caused patients to occupy hospital beds longer, and resulted in unnecessary usage of PPE and uncertainty of staff exposure to the virus in a timely manner.
- Lack of leadership: Less focus on domestic testing initially while the coronavirus task force focused on international response.
This article focuses on quantifying the impacts of rapid testing. In hard hit areas like New York and Washington state, test results took more than a week in March since the specimen was collected. Figure 1 shows a typical testing timeline. Once the specimen was collected at a test center, a courier then transports the specimens to the lab where a lab technician prioritizes the specimens for testing. Finally, results were communicated back to a test center or hospitals.
Figure 1: Typical testing timeline
We focus this analysis on the first part of this testing process (i.e., transportation of specimen from the test center to lab), which typically took more than one day. We introduce the idea of usage of Medical Drones to transport these specimens as drones are 8 to 12 times faster than a courier van. Usage of drones also reduces the exposure of health professionals to risks associated with sample collection and the transport process. Although we focus on a small part of the testing process, our interviews with WakeMed and Novant Health have stressed the importance of fast transport of medical supplies to the labs and the potential use of autonomous drones for specimen collection directly from patients. This would have further reduced testing time potentially resulting in fewer COVID-19 infections.
Figure 2: Medical Drone OEMs
Our hypothesis is that the delay in testing resulted in extra usage of PPE as patients occupied hospital beds longer and used PPE waiting for the results. NBC News reported in April that “Patients stayed in hospital beds while waiting for results, reducing the availability for other patients; staff members used precious personal protective equipment in interactions with patients they may not have needed it for; and staff members were unable to determine whether they had contracted or been exposed to the virus in a timely manner.” Using John Hopkins PPE calculator, our analysis captures the extra PPE available due to reduction in specimen transportation time from test center to lab by one day. Figure 3 describes our high-level approach.
Figure 3: John Hopkins PPE Calculator Model
We tuned the number of non-ICU days to 10 (default is 11) and assumed that 11% of patients tested were found to be positive at the end of testing cycle. In other words, it means that 89% of patients tested were occupying the hospital beds and used PPE for 1 extra day. With the changes to these variables in John Hopkins model, we calculated that this time reduction in testing cycle (due to usage of medical drones) can potentially reduce the usage of PPE per capita by 6-8%. This extra PPE (e.g. Simple Masks and N95) can be put back into the system either by making them available to general population or hospital staff.
To quantify the impact of face masks, we utilized a study performed by Eikenberry et al., from Arizona State University that models the impact of face mask use by general public. We routed the extra available face masks (Simple Masks and N95) to the general public and assumed 100% adoption. We also assumed low transmission rates in the month of March. Figure 4 shows that the peak hospitalization rate reduces by 20% while the total mortality reduces by 15% because of extra mask availability.
Figure 4: Mask coverage was calculated using John Hopkins model. Peak hospitalization rates and total mortality are calculated in relative to the base case of no mask usage.
Rapid testing would have significant impact on COVID-19 outcomes. Faster transportation by Medical Drones to move specimens and medical supplies would have enabled rapid testing and contactless logistics. For a resilient medical transportation system, metropolitan governments, hospitals and medical labs will need mature Drone Fleets to effectively tackle future health crises. Although Medical drone technology is developing fast, there exists significant gaps on the regulatory front that need to be addressed soon. 2020 was an opportunity missed but we need to be prepared for the next natural or health crisis. Bill Gates noted in 2015 that “we [America] are not ready for next epidemic…” and he was right. Let’s hope we learned our lesson.