First discovered during 1947 in Uganda from febrile rhesus macaques, Zika virus (ZIKV) is a mosquito-borne, reemerging flavivirus historically known to be present in much of Africa and Asia, occasionally causing outbreaks amongst the local populace (Haddow et al., 2012). ZIKV infections in humans are mostly asymptomatic, but a small percentage of patients may show clinical symptoms such as a fever and rash, which resolve within a week or less. Due to the benign nature of the disease, ZIKV was considered an obscure and neglected pathogen of low public health consequence. Recently, viral infection of women during pregnancy have been associated with microcephaly in their offspring (Ventura et al., 2016), and neurological disorders such as Guillain-Barré syndrome (GBS) have also been associated with prior ZIKV infections (Cao-Lormeau et al., 2016). Moreover, the ZIKV nonstructural protein 1 (NS1) has diverse electrostatic characteristics at host-interaction interfaces (Song et al., 2016). These new findings, in addition to the persistence of ZIKV in the semen of infected patients (Lazear and Diamond 2016) and possible sexual transmission of the virus (Oster et al., 2016) suggest that this virus may be more dangerous than initially thought. ZIKV first attracted global attention during 2007 when it caused an outbreak in Micronesia (Duffy et al., 2009), before spreading through Oceania in subsequent years (Cao-Lormeau et al., 2014; Dupont-Rouzeyrol et al., 2015). ZIKV eventually arrived in South America and was identified in Brazil during 2015 (Campos et al., 2015), and rapidly spread throughout the continent as well as the Caribbean islands. As of March 22nd, 2016, a total of 4,800 laboratory-confirmed, natural ZIKV infections have been reported over 46 countries, and an additional 650 imported cases have been reported by 32 more countries from Europe, Asia and North America. Aedes aegypti and Aedes albopictus are the two major vectors for ZIKV transmission. In China, Aedes aegypti is mostly distributed in Hainan, southern Guangdong and Guangxi, whereas Aedes albopictus is widespread in southern and central China (Kraemer et al., 2015). As of April 5th, 2016, a total of 13 ZIKV cases have been imported into from travelers since the first patient was reported on February 5th, 2016, and all cases have had prior travel history to South America or Oceania (Table 1). Nine travelers returned from Venezuela, one from Suriname and three from Fiji/Samoa. Five arrived in Hong Kong first and then entered mainland China via Shenzhen in Guangdong Province, seven entered Guangdong Province directly via Guangzhou, and one entered mainland China through Shanghai. Six cases showed mild clinical symptoms (ie rash and/or fever) upon arrival at Chinese customs (Fig. 1 A), and four were detected by customs staff (Table 1). The travelers who were asymptomatic at customs developed symptoms 2–9 days after returning to China (Table 1). Other potential symptoms from ZIKV disease include conjunctivitis, which was observed in case# 3 (Fig. 1 B). Due to the high density of