A duplex HiFi-LAMP assay for screening of two novel human circoviruses HCirV-1 and HCirV-2.

Circoviruses belong to the family Circoviridae, which is classified into two genera, Circovirus and Cyclovirus. Some circoviruses have been identified in various organisms and/or their fecal samples and might be associated with diseases in their hosts. However, few circoviruses are reported in human. Recently, two novel circoviruses HCirV-1 and HCirV-2 were identified in humans through next-generation sequencing and were defined as the species of Circovirus human in the family Circoviridae. Both viruses are suspected to be associated with liver diseases, particularly among immunosuppressed people, showing potential health implication. Investigation on the prevalence of both viruses, and identification of vulnerable population are important and need a rapid, accurate, and specific assay for detecting and screening the two viruses. In this study, we developed a duplex HiFi-LAMP assay for simultaneous detection of HCirV-1 and HCirV-2. The assay exhibits high sensitivity with LOD of 64 and 49 copies per 25 µL reaction for HCirV-1 and HCirV-2, respectively. The duplex assay was demonstrated to have a rapid reaction time within 35 min. Clinical screening tests showed that neither HCirV-1 nor HCirV-2 were detected among 875 patients with infection of HBV, HIV-1 or other viruses. Large-scale screening of both viruses in diverse populations is encouraged to enhance our understanding of their relevance to various diseases.