Lineages: Asian and African
Vector: Aedes aegypti mosquitoe
Rwservior/Host: non-human primate, mosquitoe, human
The Zika virus genome consists of a single-stranded positive sense RNA molecule with 10794 kb of length with 2 flanking noncoding regions (5' and 3' NCR) and a single long open reading frame encoding a polyprotein
Clinical manifestations of ZIKV infection are very similar to those of DENV and CHIKV infections, but usually milder.
Recent reports of unusually high rates of GBS and primary microcephaly, which are temporally and spatially associated with the Zika virus outbreak.
In NCBI nucleotide database, there are several whole genome sequence from different strains.
Genome from Zika virus strain ZikaSPH2015 has 10676 nucleotides.
Flaviviruses are enveloped, single-stranded, positive sense RNA viruses with 50nm in size. Full length of genome is nearly 10.5 to 11 kbp.
Analysis of the envelope protein of Zika, from Brazilian Zika SPH2015 (KU321639), indicates predicted B and T cell epitopes in peptides that are consistent to those reported for dengue, YFYF and Japanese encephalitis.
The E protein (<53 kDa) is the major virion surface protein. E is involved in various aspects of the viral cycle, mediating binding and membrane fusion. Domain III of the Zika envelope protein is likely the main specific neutralizing domain.
Typical acute symptoms persist from days to one week, and include fever (37.9°C or below), maculopapular rash (average duration 6 days), arthralgia (average duration 3.5d, range 1 to 14d) and/or conjunctivitis, myalgia, headache, retro-orbital pain and emesis.
Detection of Zika virus by RT-PCR
Detection of Zika virus in saliva
Detection of Zika virus in urine
Till now, there are specific treatments for Zika virus infection. There are no available antiviral vaccines, no drugs and other treatment.
IgM antibody response in primary flavivirus/ZIKV–infected patients is specific for ZIKV.
Zika virus transmission is associated to a mosquito bite (from an Aedes genus mosquito) and was isolated in 1948 from a macerate of mosquitoes of the Aedes africanus species collected at the Zika forest.
Since initial discovery of Zika virus, early virological and serological studies from the 1950s to 1980s showed that Zika virus infection is predominantly limited to African and Asian countries.
In the absence of vaccines or chemoprophylaxis, the prevention of Zika virus infection follows the general rules for other vectorborne infections. Broadly speaking, this involves two major areas, personal protection through bite avoidance and vector control.
The first major epidemic outside Africa occurred in Yap Island of the Federated States of Micronesia in 2007.
Another major epidemic occurred in the western Pacific islands of French Polynesia and New Caledonia in 2013-2014.
At present, the only flaviviral vaccines available for human use are yellow fever (live attenuated), Japanese encephalitis (inactivated, live attenuated, and chimeric), tick-borne encephalitis (inactivated) vaccines
The outbreak on Yap Island in 2007 shows that ZIKV illness has been detected outside of Africa and Asia.
Aedes mosquitoes are the main vectors, in particular, Ae. aegypti. Ae. Albopictus is another potential vector.
Due to the fact that currently no commercial tests allowing for the serological diagnosis of ZIKV infection are available, ZIKV acute infection may be diagnosed by RT-PCR (reverse transcription polymerase chain reaction) directly from virus RNA in patient's serum