Surveillance of mosquito-borne infectious diseases in febrile travelers entering China via Shenzhen ports, China, 2013.

BACKGROUND

About 100 million passengers enter China via Shenzhen ports every year and such huge populations increase the risk of various infectious diseases, particularly mosquito-borne diseases, entering China. This paper reports the testing and monitoring of mosquito-borne diseases in febrile travelers through Shenzhen ports in 2013.

METHODS

The blood samples of 619 febrile cases were collected and the serum of each sample was used for the specific gene amplification and IgM antibody detection of five typical mosquito-borne pathogens: Dengue virus (DENV), Japanese encephalitis virus (JEV), Chikungunya virus (CHIKV), yellow fever virus (YFV), and West Nile Virus (WNV). Additionally, malaria was diagnosed by rapid diagnostic tests (RDTs).

RESULTS

In total, 34 cases were detected of DENV infection (serotype I to IV), 17 cases of JEV infection, 2 cases of CHIKV infection, and 3 cases of malaria infection. No virus genes or IgM antibodies of YFV or WNV were detected in the samples. DENV, JEV and CHIKV cases were mainly from Southeast Asia, while malaria cases from Africa.

CONCLUSIONS

DENV, JEV and CHIKV were the primary pathogens imported via Shenzhen ports. International travelers with mosquito-borne infections would accelerate the spread of these diseases, thus reinforcing the need for surveillance of mosquito-borne infections at ports should become a high priority.