Development and evaluation of a loop-mediated isothermal amplification assay for clinical diagnosis of respiratory human adenoviruses emergent in China

Three human adenovirus (HAdV) genotypes, HAdV-7, HAdV-14, and HAdV-55, emerged as the most prevalent variants in China over the past decade and caused both sporadic, fatal cases and frequent, large outbreaks. Early diagnosis is essential to control infections and endemics. Here, we established a loop-mediated isothermal amplification (LAMP) assay coupled with an instrument-free nucleic acid extraction device recently developed by our group; the assay could detect all the 3 prevalent HAdV genotypes. Specificity analysis showed no cross-reactivity with other common respiratory pathogens and the analytical sensitivity was as low as 10 copies/mL. All detection steps could be completed within 1 hour. The assay's performance was evaluated using clinical samples and compared with the gold standard RT-PCR method, showing highly consistent results. The LAMP assay developed here could be readily used in basic laboratory facilities and with minimal DNA extraction equipment, and as a reliable screening test in a resource-limited setting. (c) 2021 Elsevier Inc. All rights reserved.

Automated summary

The LAMP assay developed in this study can rapidly and accurately detect the three most prevalent HAdV genotypes in China, suitable for resource-limited settings, and showing highly consistent results with the gold standard RT-PCR method.