On-site visual diagnosis of parapoxvirus infection using a portable cordless incubator.

A portable cordless incubator was developed for on-site visual diagnosis of parapoxvirus infection on farms and in areas with no electricity or laboratory equipment. The battery-powered thermoregulator can maintain a stable temperature for more than 1 h. The incubator successfully amplified parapoxvirus DNA isolated from sheep and wild Japanese serows (Capricornis crispus) by loop-mediated isothermal amplification (LAMP). Although different absorbance values were obtained for the LAMP reactions performed using the same sample on the incubator and the turbidimeter, visual assessments of whether the results were positive or negative were the same irrespective of the platform used to perform the LAMP reaction. Consequently, using the portable cordless incubator in conjunction with the LAMP assay is considered to be a powerful tool for on-site visual diagnosis of parapoxvirus infection on farms with no electricity.