Researchers have identified key genes behind the infectivity of a virus that causes hand, foot, and mouth disease. Humans are the only known mammalian host, but in 2014, strains were bred that were capable of infecting mice and primate cell lines. These strains had mutant versions of the virus coat proteins. In this study, the same research group, led by Kaw Bing Chua and Vincent Chow at the National University of Singapore, introduced the mutations into the non-infectious strain individually and in combinations.

The flaviviruses dengue virus (DENV) and Zika virus (ZIKV) are severe health threats with rapidly expanding ranges. To identify the host cell dependencies of DENV and ZIKV, we completed orthologous functional genomic screens using RNAi and CRISPR/ Cas9 approaches. The screens recovered the ZIKV entry factor AXL as well as multiple host factors involved in endocytosis (RAB5C and RABGEF), heparin sulfation (NDST1 and EXT1), and transmembrane protein processing and maturation, including the endoplasmic reticulum membrane complex (EMC).

The human disease Japanese encephalitis (JE) can be prevented by vaccination, although it is not entirely clear if the emerging JEV G5 genotype can be controlled using the vaccine based on the G3 genotype. Consequently, we systematically compared G3 and G5 cross-neutralizing immune responses in vaccinated humans and, separately, cross-protective immune responses in mice using the current G3 JE vaccine to induce the immunity.

Zika virus (ZIKV) is an arthropodborne member of the genus Flavivirus of the Spondweni serocomplex and is transmitted by Aedes mosquitoes (primarily Ae. aegypti in urban and periurban cycles). ZIKV emerged in Africa and has caused outbreaks of febrile disease that clinically resemble dengue fever and other arboviral diseases but has been linked to neurologic syndromes and congenital malformation.

Zika virus (ZIKV), an emerging flavivirus, generally causes mild infection in humans but is associated with severe neurologic complications and adverse fetal outcomes. ZIKV is transmitted to humans primarily by aedes mosquitoes. However, there is some evidence of sexual transmission. Two studies have shown the presence of infectious ZIKV in semen. A recent article described detection of ZIKV RNA in semen 62 days after the onset of illness, but infectious virus was not cultured.

The recent rapid spread of Zika virus and its unexpected linkage to birth defects and an autoimmuneneurological syndrome has generated worldwide concern. Zika virus is a flavivirus like dengue, yellow fever and West Nile viruses. We present the 3.8Å resolution structure of mature Zika virus determined by cryo-electron microscopy. The structure of Zika virus is similar to other known flavivirus structures except for the ~10 amino acids that surround the Asn154 glycosylation site found in each of the 180 envelope glycoproteins that make up the icosahedral shell.