Analysis of the local dengue fever outbreak in the north of Henan Province in 2019 / 中华微生物学和免疫学杂志

ABSTRACT

Objective:To provide data support for the prevention and control of dengue fever in Henan Province by analyzing the molecular epidemiological and etiological characteristics of dengue fever outbreaks in Puyang in 2019.Methods:Blood samples were collected from all suspected cases of dengue fever. The antigen, antibody and nucleic acid of dengue virus (DENV) were detected. The E gene was amplified by viral nucleic acid extraction and sequenced. Phylogenetic tree was constructed to trace the source of infection. Results:A total of 61 local cases of dengue fever were reported, and no deaths were reported. Among them, 4 cases (72.13%) were positive for DENV NS1 antigen; 16(26.23%) cases were positive for specific IgM; 38(62.30%) cases were positive for specific IgG; 34 cases (54.10%) were positive for dengue nucleic acid testing. Ten dengue virus strains were isolated, all of which were dengue virus type 1(DENV-1). Sequence analysis of E gene suggested it belonged to the same clade as Henan201903 strain imported from Cambodia to Zhumadian, Henan in 2019, with the highest homology. Conclusions:The dengue fever epidemic in Henan Province was caused by DENV-1, which might be improted from Cambodia, Singapore, Myanmar and other Southeast Asian countries. Therefore, the surveillance of DENV in people returning from Southeast Asia should be strengthened.