title: Response of primary vectors and related diseases to impoundment by the Three Gorges Dam.
abstract: OBJECTIVE
  To investigate the impact of the Three Gorges Dam on the local ecological environment. We conducted a 3-year cross-sectional survey of natural focus infectious diseases in the area before and after the water level rose to 156 m to evaluate the dam's health impacts.
  
  
  METHODS
  Direct and indirect immunofluorescence methods were applied to detect rat antigen and antibody of haemorrhagic fever with renal syndrome (HFRS). Fresh rat kidneys were inoculated in Korth's culture medium to detect Leptospira. A group of captured crabs were ground to observe the metacercariae of Paragonimus. Serum samples were collected from healthy local individuals. ELISA kits were used to detect human antibody against HFRS and paragonimiasis. Human Leptospira infections were detected by a microscopic agglutination test.
  
  
  RESULTS
  Upstream rodent density increased significantly with Rattus flavipectus and Apodemus agrarius as the major pathophoric genera. The infection rate of human HFRS and Leptospira in the upstream human population samples was significantly higher than in the downstream samples and correlated with the increase in rodent density. Paragonimus infection rates remained at a low level during the study. Culex pipiens fatigan and Armigeres obturbans were the dominant species of mosquito.
  
  
  CONCLUSIONS
  The creation of the Three Gorges Dam changed the proliferation of intermediary agents of diseases, but not notably. However, the ecological effects on the environment may require a prolonged period of time to manifest themselves; thus, long-term and effective surveillance of vectors and related diseases needs to be established.
authors.affiliation: MOE Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Wuhan, PRC.
authors.forename: Xu
authors.initials: X
authors.lastname: Zhang
authors.forename: Liangbin
authors.initials: L
authors.lastname: Peng
authors.forename: Wendong
authors.initials: W
authors.lastname: Liu
authors.forename: Lirui
authors.initials: L
authors.lastname: Fan
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
authors.forename: Guangjie
authors.initials: G
authors.lastname: Chen
authors.forename: Pan
authors.initials: P
authors.lastname: He
authors.forename: Ruixiao
authors.initials: R
authors.lastname: Wu
authors.forename: Anping
authors.initials: A
authors.lastname: Liu
authors.forename: Yexun
authors.initials: Y
authors.lastname: Yang
authors.forename: Xiaogai
authors.initials: X
authors.lastname: Yu
authors.forename: Luojia
authors.initials: L
authors.lastname: Yun
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000818:Animals; D003386:Brachyura; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D009033:Culicidae; D004197:Disease Reservoirs; D004199:Disease Vectors / Q000145:classification*; D019353:Endemic Diseases / Q000706:statistics & numerical data; D004777:Environment; D004797:Enzyme-Linked Immunosorbent Assay; D019085:Fluorescent Antibody Technique, Direct / Q000379:methods; D019084:Fluorescent Antibody Technique, Indirect / Q000379:methods; D006480:Hemorrhagic Fever with Renal Syndrome / Q000097:blood* / Q000453:epidemiology / Q000276:immunology; D006801:Humans; D007223:Infant; D007922:Leptospirosis / Q000097:blood* / Q000453:epidemiology / Q000276:immunology; D051379:Mice; D008875:Middle Aged; D010237:Paragonimiasis / Q000097:blood* / Q000453:epidemiology / Q000276:immunology; D051381:Rats; D045483:Rivers / Q000382:microbiology*; D055815:Young Adult
keywords: Three Gorges Dam; haemorrhagic fever with renal syndrome; leptospirosis; malaria; paragonimosis; rat density