Anusara JitsatjaSuwipa RamphanPloenphit PrommaAtichat KuadkitkanNitwara WikanMongkol UiprasertkulChayawat PhatihattakornDuncan R. SmithMahidol UniversityFaculty of Medicine, Siriraj Hospital, Mahidol University2020-08-252020-08-252020-08-01Archives of Virology. Vol.165, No.8 (2020), 1791-180114328798030486082-s2.0-85085901487https://repository.li.mahidol.ac.th/handle/20.500.14594/57941© 2020, Springer-Verlag GmbH Austria, part of Springer Nature. In this study, we compared the characteristics of two strains of Zika virus (ZIKV) isolated in Thailand, one isolated from a febrile patient and one isolated from tissues of a fetus medically terminated due to congenital Zika syndrome (CZS). Replication profiles showed that the isolate from the fetal tissues replicated significantly more slowly than the fever-associated isolate in human lung A549 cells during the first 24 hours postinfection but showed a similar growth profile over longer-term infection. A much smaller difference was observed in Aedes albopictus C6/36 cells. In a quasispecies analysis, a high proportion (approximately 20%) of nonfunctional genomes was identified, caused by an adenine insertion in the prM gene. This insertion was found to be present in two Thai fever strains and as such may represent a common feature of Thai endemic ZIKV. Comparison between viral RNA copy number and viral titer showed that the isolate from fetal tissues was produced more efficiently than the fever-associated isolate. Together, these results suggest that different ZIKV isolates differ in their replication capacity, and this might contribute to the fetotropic potential of a particular strain.Mahidol UniversityImmunology and MicrobiologyArticleSCOPUS10.1007/s00705-020-04667-7