Volume 22, Number 6—June 2016
Letter
Zika Virus in a Traveler Returning to China from Caracas, Venezuela, February 2016
On This Page
To the Editor: Zika virus (ZIKAV), a member of the Flaviviridae family, is primarily transmitted through Aedesspp. mosquitoes, and evidence of vertical, sexual, and blood transmission of ZIKAV has been reported (1–3). The virus has spread rapidly across Latin America and the Caribbean since the end of 2014 and has been linked to an increase in neurologic disorders and neonatal malformations in these areas (4). ZIKAV has the potential to spread internationally through the carriage of goods and travelers (5). Traveler volume between China and areas with autochthonous transmission of ZIKAV is increasing; in 2015, China received ≈84,000 travelers who had departed from international airports in Brazil (5). The Ae. aegypti mosquito, the competent vector for ZIKAV, is found in areas of Hainan, Guangdong, and Yunnan provinces on the mainland of China, where the known distribution is limited to areas below 22° latitude. However, Ae. albopictus mosquitoes are widely distributed, extending from the southern reaches to the northern and western parts of China, with north fringes from Shenyang in Liaoning Province, through Tianshui and Longnan in Gansu Province, to Motuo in Tibet (6). Surveillance of ZIKAV infection among Chinese travelers has been enhanced since January 2016. We report the clinical and laboratory findings for a case ZIKAV infection imported from Venezuela.
A previously healthy 34-year-old Chinese man was admitted to the Hospital of Ganxian on February 6, 2016. He had worked in Caracas, Venezuela, during January 1–February 2 and had onset of fever (38.0°C), headache, and dizziness on January 28. He subsequently had rash, chills, retro-orbital pain, and mild diarrhea on February 2, the day on which he departed from Caracas and traveled to Jiangxi Province via Paris and Hong Kong, arriving in Shenzhen, China, on February 5. At the time of hospital admission, the patient had fever (36.7°C), headache, conjunctivae, rash on his back and face, retro-orbital pain, and mild diarrhea. General clinical examination was unremarkable. Results of a complete blood cell count and liver function tests were within reference ranges.
Serum samples were collected at day 9 and day 10 after symptom onset, and urine samples were collected once a day from day 10 through day 14. In the 2 serum samples, no dengue virus (DENV) or chikungunya virus (CHIKV) IgM or IgG were detected by a Panbio IgM and IgG capture ELISA for DENV (Panbio, Queensland, Australia) or by an indirect immunofluorescence assay slide test kit for CHIKV (EUROIMMUN AG, Lübeck, Germany). Serum and urine samples were negative for DENV nonstructural protein 1 (NS1) antigen on an NS1-ELISA test kit (Wantai Bio-Pharm, Beijing, China). To detect virus RNA in samples, in-house–designed probe and primers specific to DENV and CHIKV were used (7). The PCR for ZIKAV was targeted to the NS1 gene. RNA was extracted from 140 μL of serum or urine by using the QIAamp Viral RNA Mini Kit (QIAGE, Hilden, Germany). Amplification reactions were performed by using the AgPath-ID One-Step RT-PCR Kit (Ambion, Carlsbad, CA, USA). A standard curve with serial dilutions of known concentrations of in vitro–transcribed RNA from a reference plasmid was used to estimate viral load in samples. Test results for DENV and CHIKV were negative. However, the serum sample collected at day 9 was positive for ZIKAV RNA (viral load 1.4 × 104 copies/mL), and ZIKAV RNA was detected from urine samples collected on days 10, 11, and 12 (viral loads 8.6 × 104, 4.5 × 104, and 1.2 × 104 copies/mL, respectively).
Next-generation genomic sequencing of the ZIKAV genome was conducted by using the MiSeq platform (Illumina, Hayward, CA, USA) on serum and urine samples. A 1,813-bp of partial genome sequences (strain VE_Ganxian, GenBank accession no. KU740199) was obtained from urine and was used for comparing with selected other strains from GenBank. Phylogenetic analysis showed that the virus was of Asian lineage (Figure). Pairwise genetic distance calculation indicated that the sequence was most closely related to other viruses reported from French Polynesia in 2013 (strain H/PF/2013), the Caribbean in 2014 (strain Haiti/1225/2014), and Latin America in 2015 (strain ZikaSPH2015), having a 99.4% similarity in sequence.
The clinical findings for the patient were similar to those previously reported among ZIKAV-infected patients (9), although no arthralgia was apparent. Viral RNA remained detectable for 9 days after symptom onset in serum and for an additional 3 days in urine. We did not test this patient’s semen and thus cannot comment on risk for onward sexual transmission; however, the patient was told about the risks for sexual transmission of ZIKAV and was advised to adopt safer sexual practices or to abstain from sexual activity for at least 1 month after recovery. In February, the mosquito density is low in Jiangxi Province (10), suggesting that this imported case is unlikely to cause mosquitoborne transmission. However, with the onset of summer and increased density of Aedesmosquitos, the risk for onward transmission of travel-associated ZIKAV should not be overlooked.
Acknowledgments
We thank the clinical workers from Ganxian Hospital for collecting the samples, and we thank all related laboratory and administrative personnel at the Chinese Center for Disease Control and Prevention and Jiangxi Province Center for Disease Control and Prevention.
This study was funded through the National Key Project for Infectious Disease (grant no. 2016ZX10004101).
References
- Besnard M, Lastere S, Teissier A, Cao-Lormeau V, Musso D. Evidence of perinatal transmission of Zika virus, French Polynesia, December 2013 and February 2014. Euro Surveill. 2014;19:20751. DOIPubMed
- Musso D, Roche C, Robin E, Nhan T, Teissier A, Cao-Lormeau VM. Potential sexual transmission of Zika virus. Emerg Infect Dis. 2015;21:359–61.DOIPubMed
- Ioos S, Mallet HP, Leparc Goffart I, Gauthier V, Cardoso T, Herida M. Current Zika virus epidemiology and recent epidemics. Med Mal Infect.2014;44:302–7. DOIPubMed
- Pan American Health Organization, World Health Organization. Epidemiological update: neurological syndrome, congenital anomalies, and Zika virus infection (17 January 2016) [cited 2016 Mar 7]. http://www.paho.org/hq/index.php?option=com_docman&task=doc_view&Itemid=270&gid=32879&lang=en
- Bogoch II, Brady OJ, Kraemer MU, German M, Creatore MI, Kulkarni MA, Anticipating the international spread of Zika virus from Brazil. Lancet.2016;387:335–6. DOIPubMed
- Xu RM. Geographic distribution of Aedes aegypti and Aedes albopictus. In: Lu, ML, ed. Vector of dengue fever and its prevention and control in mainland China. Gui Zhou (China): Gui Zhou People’s Press; 1990. p. 51–55.
- Pang Z, Li A, Li J, Qu J, He C, Zhang S, Comprehensive multiplex one-step real-time TaqMan qRT-PCR assays for detection and quantification of hemorrhagic fever viruses. PLoS ONE. 2014;9:e95635. DOIPubMed
- Tamura K, Nei M. Estimation of the number of nucleotide substitutions in the control region of mitochondrial DNA in humans and chimpanzees. Mol Biol Evol. 1993;10:512–26 .PubMed
- Duffy MR, Chen TH, Hancock WT, Powers AM, Kool JL, Lanciotti RS, Zika virus outbreak on Yap Island, Federated States of Micronesia. N Engl J Med. 2009;360:2536–43. DOIPubMed
- Lu L, Lin H, Tian L, Yang W, Sun J, Liu Q. Time series analysis of dengue fever and weather in Guangzhou, China. BMC Public Health. 2009;9:395.DOIPubMed
Figure
Suggested citation for this article: Li J, Xiong Y, Wu W, Liu X, Qu J, Zhao X, et al. Zika virus in a traveler returning to China from Caracas, Venezuela, February 2016 [letter]. Emerg Infect Dis. 2016 June [date cited]. http://dx.doi.org/10.3201/eid2206.160273
1These authors contributed equally to this article.
No hay comentarios:
Publicar un comentario