An outbreak of dengue virus serotype 1 infection in Cixi, Ningbo, People's Republic of China, 2004, associated with a traveler from Thailand and high density of Aedes albopictus.
Autochthonous dengue infections have not been reported in Ningbo, People's Republic of China since 1929. In August-October 2004, an outbreak of dengue fever was confirmed in Xiaolin, Cixi, Ningbo. Of 83 cases reported, 68 were laboratory confirmed. Fifty-three percent (34 of 64) of the cases had IgM antibodies to dengue virus. Dengue virus serotype-1 was isolated from two cases. The outbreak was linked to a traveler who returned from Thailand. Phylogenetic analysis showed that the Ningbo isolate was closely associated to strains from Thailand. Prevalence of dengue-specific IgG in asymptomatic residents was significantly higher in the epidemic-stricken area than in a control area. High density of Aedes albopictus, which resulted from waterlogging caused by Typhoon Rananim and lifestyle of local residents, was responsible for rapid spread of the virus. Eradication of mosquito infestation might interrupt transmission. This outbreak underscores the importance of maintaining surveillance and control of potential vectors for the control of emerging infectious diseases.
Xu
Guozhang
G
Department of Infectious Diseases, Center of Disease Prevention and Control of Ningbo City, Ningbo, Zhejiang, People's Republic of China. xugz@nbcdc.org.cn , donghj@nbcdc.org.cn
Dong
Hongjun
H
Shi
Nanfeng
N
Liu
Shijian
S
Zhou
Aiming
A
Cheng
Zhihua
Z
Chen
Guohua
G
Liu
Jianyi
J
Fang
Ting
T
Zhang
Hongwei
H
Gu
Chunying
C
Tan
Xiaojie
X
Ye
Jianjie
J
Xie
Shuyun
S
Cao
Guangwen
G
D000293:Adolescent; D000328:Adult; D000330:Aedes / Q000382:microbiology*; D000368:Aged; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D016000:Cluster Analysis; D003715:Dengue / Q000453:epidemiology* / Q000635:transmission; D003716:Dengue Virus / Q000235:genetics / Q000302:isolation & purification*; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D007223:Infant; D007303:Insect Vectors / Q000382:microbiology*; D008297:Male; D008875:Middle Aged; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012367:RNA, Viral / Q000737:chemistry / Q000235:genetics; D012424:Rural Population; D013785:Thailand / Q000453:epidemiology; D014195:Travel
D000914:Antibodies, Viral; D012367:RNA, Viral