Delay of molecular SARS-CoV-2 testing and turnaround time in Mexico and Colombia

Nunez, I.; Belaunzaran-Zamudio, P. F.; Caro-Vega, Y.

Objective: To quantify the delay in SARS-CoV-2 real time polymerase chain reaction (RT-PCR) testing and test result reporting in Mexico and Colombia, and to assess the relation between margination status and these delays. Methods: We quantified time in days from symptom onset until testing (latency one) and delay in test results report (latency two) using freely available country-wide open data from Mexico and Colombia. Directed acyclic graphs were built to determine which associations were appropriate to assess. Stratification by margination status, state and hospitalization status was used to determine corresponding associations. Results: In almost all the study period latency two was longer than latency one. Median latency one was 3 (IQR 0-6) days and latency two 7 (IQR 4-11) days in Colombia, while in Mexico they were 3 (IQR 1-5) days and 4 (IQR 3-6) days. In Colombia, worse margination status prolonged latency two. In Mexico, a lower number and percentage of point-of-care (POC) tests in areas with worse margination. Conclusion: POC tests must be used as a widespread means to reduce latency two, and until then should be prioritized in areas with longer latency two. An unequal distribution of this resource should be avoided.