Objective: To analyze data gathered from the laboratory records related to imported
Dengue cases in Henan province in 2018. Methods: Suspected
Dengue cases were found out through the
Dengue fever surveillance network from the National infectious Disease reporting management information system. Serum samples of suspected
Dengue cases were collected while case study and tested for
Dengue NS1
antigen,
IgM,
IgG antibodies and
Dengue RNA in Henan province in 2018. According to the standardized
Dengue diagnosis criteria, confirmed cases were identified under the results of testing.
Dengue RNA was checked by Real-time PCR genotyping and amplification of E gene in the samples being tested, before the PCR products were sequenced and analyses of homological and phylogenetic were performed. Results: In 2018, a total of 29 cases of
Dengue fever was reported in Henan province, with all of which were imported cases, mainly from Southeast Asian countries and Africa. Majority of the cases were young and middle-aged farmers under 45 years old, and the number of males was significantly higher than that of females. The imported cases were dispersed in time and space. Among the 29
Dengue reported cases, 22 cases were with NS1
antigen and/or
IgM positive through testing, while 6 cases were positive by detection of the Dengue virus
RNA. These 6 samples with
Dengue RNA were genotyped successfully, including 3 cases of Dengue virus type 1 and 3 cases of type 2. One of the Maldives import Dengue virus type 2 samples was sequenced. Result showed that the sequence belonged to the Asian Ⅰ genotype, which was most consistently similar to the Cambodia's Dengue virus type 2 JF730046, identified in 2008. Conclusions: The incidence of imported
Dengue fever cases increased significantly in Henan province in 2018, compared to that in 2017, but fortunately did not cause any local epidemics.