Home Testing for Contagious Illness: Historical Context and Modern Caveats.

Dozens of over-the-counter tests offer to evaluate users for an array of contagious illnesses, including sexually transmitted infections, acute respiratory infections like coronavirus disease 2019 (COVID-19) and influenza, and complicated chronic infections like Lyme disease, tuberculosis, and human immunodeficiency virus (HIV). Diagnosing any of these conditions in a home setting raises both logistical and ethical issues that may prevent home testing from becoming the public health benefit its advocates envision. Over the last century, early home tests such as the first urine glucose screening tests for diabetes and the first home pregnancy tests generated very similar expectations of substantial public health benefits. These tests helped many individual patients, but neither proved to be a particularly effective public health tool. Home testing for contagious illness raises additional issues of quarantine, contact tracing, and treatment that are yet to be addressed in any systematic way. The widespread enthusiasm for patching suboptimal healthcare systems with home testing seems premature.