Foot-and-Mouth disease Virus (FMDV) is a highly infectious RNA virus that causes severe economic losses in cloven-hoofed animals. Early detection is needed to control epidemics, and loop-mediated isothermal amplification (LAMP) can be performed using inexpensive and commonly available equipment with a short processing time, but existing assays for FMDV still require an additional reverse transcriptase enzyme to convert RNA to cDNA prior to amplification. We sought to develop a novel RT-LAMP assay for FMDV with carboxamide and N-alkylcarboxamide additives to reduce non-specific amplification in combination with an improved commercially available polymerase (Bst 3.0) with efficient reverse transcriptase activity. SYBR Green I dye was used for sensitive visual detection of amplification products from our LAMP assay within 15 min without the need for a colorimeter. In the presence of a carefully titrated mixture of carboxamide and N-alkylcarboxamide additives, longer reactions of up to 1 h were also possible on both RNA and cDNA without the appearance of non-specific amplification products, thereby increasing the potential robustness of the assay by allowing a greater window of time in which to detect weak positives.

口蹄疫病毒（FMDV）是一种高度传染性的RNA病毒，会给偶蹄动物造成严重的经济损失。控制流行病需要早期检测，环介导的等温扩增 (LAMP) 可以使用廉价且常用的设备进行，处理时间短，但现有的 FMDV 检测仍需要额外的逆转录酶来将 RNA 转化为 cDNA放大。我们试图开发一种新的 RT-LAMP 检测方法，用于使用羧酰胺和N-烷基甲酰胺添加剂与具有高效逆转录酶活性的改进的市售聚合酶 (Bst 3.0) 相结合，可减少非特异性扩增。SYBR Green I 染料用于在 15 分钟内对我们的 LAMP 分析中的扩增产物进行灵敏的视觉检测，无需色度计。在仔细滴定的甲酰胺和N-烷基甲酰胺添加剂混合物存在的情况下，RNA 和 cDNA 也可以进行长达 1 小时的更长反应，而不会出现非特异性扩增产物，从而通过以下方法提高测定的潜在稳健性允许更大的时间窗口来检测弱阳性。