Nucleic Acid Point-of-Care Testing to Improve Diagnostic Preparedness

Abstract

Testing programs for severe acute respiratory syndrome coronavirus 2 have relied on high-throughput polymerase chain reaction laboratory tests and rapid antigen assays to meet diagnostic needs. Both technologies are essential; however, issues of cost, accessibility, manufacturing delays, and performance have limited their use in low-resource settings and contributed to the global inequity in coronavirus disease 2019 testing. Emerging low-cost, multidisease point-of-care nucleic acid tests may address these limitations and strengthen pandemic preparedness, especially within primary healthcare where most cases of disease first present. Widespread deployment of these novel technologies will also help close long-standing test access gaps for other diseases, including tuberculosis, human immunodeficiency virus, cervical cancer, viral hepatitis, and sexually transmitted infections. We propose a more optimized testing framework based on greater use of point-of-care nucleic acid tests together with rapid immunologic assays and high-throughput laboratory molecular tests to improve the diagnosis of priority endemic and epidemic diseases, as well as strengthen the overall delivery of primary healthcare services.

Keywords: COVID-19; diagnosis; nucleic acid test; point-of-care; primary healthcare.

Figure 1.

Inequity exists in access to testing: coronavirus disease 2019 (COVID-19) testing rates per 1000 vs gross domestic product per capita. Lower-income countries have conducted fewer COVID-19 tests to date than higher-income countries. Despite the deployment of rapid antigen assays since late 2020, the gap in testing rates continued to increase in 2021. Data source: Our World in Data [2].^∗World Health Organization targets: 1 test per 1000 population per week [3]. Abbreviations: DRC, Democratic Republic of the Congo; UK, United Kingdom; WHO, World Health Organization.

Figure 2.

Framework for diagnostic preparedness in pandemic disease control. Preparedness for pandemic diseases requires the rapid availability of diagnostics in 3 distinct but interconnected levels. Diagnosis in reference laboratories and central health facilities should be performed using high-throughput technology. Primary healthcare facilities, which serve as the main interface between health services and communities, have the most significant diagnostic gap and should widely implement point-of-care nucleic acid assays to enable same-day testing of epidemic and endemic diseases. Mass screening at community and primary healthcare levels should be conducted using rapid immunological assays that can be developed and deployed rapidly. Abbreviations: COVID-19, coronavirus disease 2019; HIV, human immunodeficiency virus; RDT, rapid diagnostic test; TB, tuberculosis.