The geographic range of arthropod-borne viruses has been rapidly increasing in recent years. multivariable logistic analysis, age (45+ vs. 1C25; OR = 3.4, 95% C.I.: 1.8C6.3), occupation (mostly outdoor vs. mostly indoor; OR = 2.4, 95% C.I.: 1.1C5.2), and skin type(type I/II vs. type III/IV and type V/VI; OR = 4.3, 95% C.I.: 1.7C10.8 and OR = 2.7, 95% C.I.: 1.3C5.5 respectively, skin types based on Fitzpatrick scale) showed significant association with WNV seroreactivity. We collected 2,015 mosquitoes in 136 pools belonging to 5 genera and 14 species. Three pools of complex were positive for WNV RNA using real-time reverse transcription polymerase chain reaction (rtRT-PCR). ZIKV RNA was not detected in any of the pools. All WNV ELISA reactive serum samples were negative for WNV RNA. In conclusion, we provided evidence of the establishment of WNV in southern Iran and no proof of ZIKV in serum samples or in mosquito vectors. The establishment of an organized arbovirus surveillance system and active case finding strategies seems to be necessary. Author summary In recent decades mosquito-borne viruses Vincristine sulfate have reached and adapted to new habitats, and now they can be found in nearly all continents. Facilitated goods transportation, live stock exchange, people travelling more easily, and most importantly world climate alterations, might be some of the reasons for this mosquito habitat spreading. Emergence of WNV Vincristine sulfate in North America, Europe, and most Mediterranean countries like Turkey, Greece and Israel is evidence of this spreading. Furthermore, emergence and re-emergence of some of these mosquito borne viruses in new areas may be accompanied with changes in their pre-known pathogenesis. Re-emergence of ZIKV in the South Pacific and America from 2007 to 2016 was accompanied with an increase in neurovirulent diseases and congenital malformations. In this study, we evaluated the presence of WNV and ZIKV via serological and genome detection in human samples and mosquitoes Vincristine sulfate (viral genome analysis) from southern Iran. This region is on the coast with a warm and tropical climate suitable for inhabitation and expansion of the vectors harboring these two viruses. We caught a large spectrum of mosquitoes from these areas. After classification, we analyzed the mosquitoes pools for Vincristine sulfate WNV and ZIKV genomic RNA. Vincristine sulfate Our results showed that 20.6% of the studied human samples were IgG reactive to WNV while no antibodies against ZIKV were detected. We found WNV RNA genome in three mosquitoes pools. The genomic analysis was negative for ZIKV in both human and mosquito samples. Based on the results WNV is notably circulating in southern Iran; while no evidence of ZIKV infection in people or circulation in any of the vectors was observed. Introduction West Nile virus (WNV) and Zika virus (ZIKV) are mosquito-transmitted viruses from the genus (Ae.), such as and [10, 11]. As most studies have shown, mosquitoes are considered the primary ZIKV vectors; however, transmission of ZIKV may involve mosquitoes of other genuses, since the virus has also been isolated from and many other mosquito species in nature [12C14]. The range of natural hosts and vectors could expand through the virus spread and evolution. Any countries where and mosquitoes are present, have a high potential for geographic expansion of ZIKV [11]. WNV is the most widespread member of the Japanese encephalitis virus complex in the world. This virus expanded FGF5 its range from a small area of sub-Saharan Africa to almost all continents in the last 25 years [15]. Several outbreaks involving high number of neuroinvasive disease cases have.