The emergence and re-emergence of Zika virus (ZIKV), is a cause for international concern. These highly pathogenic arboviruses represent a serious health burden in tropical and subtropical areas worldwide. Despite these burdens, antiviral therapies do not exist, and inhibitors of ZIKV are therefore urgently needed. To elucidate the anti-ZIKV effect of lycorine, we used reverse transcription-quantitative real-time PCR (qRT-PCR), immunofluorescence, Westernwestern blot, and plaque forming assay to analyse viral RNA (vRNA), viral protein, progeny virus counts, and validated inhibitors in vitro using a variety of cell lines. Additionally, we found that lycorine acts post-infection according to time-of-addition assay, and inhibits RdRp activity. Lycorine protected AG6 mice against ZIKV-induced lethality by decreasing the viral load in the blood. Due to its potency and ability to target ZIKV infection in vivo and in vitro, lycorine might offer promising therapeutic possibilities for combatting ZIKV infections in the future.

Dengue fever is a major worldwide public health problem that, as estimated by the WHO, causes epidemics in over 100 countries, resulting in hundreds of millions of dengue virus (DENV) infections every year. In China, dengue fever mainly occurs in coastal areas. Recurring dengue outbreaks were reported by Guangdong Province almost every year since the first epidemic in 1978. DENV infections persisted in Guangzhou in consecutive years since 2000, with the dengue epidemic reaching a historical peak in 2014. Because Guangzhou is one of the largest cities for opening up in China, understanding the epidemiological characteristics of dengue fever in the city can hopefully provide a significant basis for developing effective dengue prevention strategies. In this study, a total of 34 DENV strains, including 29 DENV-1 strains and 5 DENV-2 strains, were isolated from a blood samples drawn from patients who were diagnosed with dengue fever by hospitals in Guangzhou during 2018. To explore the epidemiological characteristics of dengue fever, the envelope (E) gene obtained from the isolates was amplified for phylogenetic analysis. The results from the phylogenetic analysis showed that DENV in Guangzhou was mainly imported from Southeast Asian countries. Additionally, propagation paths based on phylogeographical analysis suggested potential local dengue transmission in Guangzhou.