[Effectiveness of routinely used assays for the diagnosis of schistosomiasis japonica in the field].
OBJECTIVE
To evaluate the effectiveness of routinely used assays for schistosomiasis diagnosis in the field.


METHODS
From late November to early December 2005, 6-65 years old inhabitants from 3 endemic villages were examined by Kato-Katz technique (3 thick smears) and nylon bag sedimentation/hatching method. At the same time, dipstick dye immunoassay(DDIA), fast enzyme linked immunosorbent assay (F-ELISA), indirect haemagglutination test A (IHA-A) and B ( IHA-B) were carried out in parallel


RESULTS
1864 people were examined by stool examination with an average positive rate of 9.7%. The missing rate of DDIA was relatively stable in medium and heavily endemic areas of schistosomiasis. The missing rate of nylon bag sedimentation/hatching method was 25% and relatively stable when the number of eggs per gram of feces(EPG) was larger than 100. The average positive rate of DDIA, F-ELISA, IHA-A and IHA-B was 47.8%, 50.0%, 66.3% and 40.1% respectively. Using stool examination as the gold standard, the sensitivity of DDIA, F-ELISA, IHA-A and IHA-B was 75.3%, 65.8%, 85.6% and 76.0%; and the specificity was 55.1%, 51.7%, 35.7% and 63.6%, respectively. Among the four sero-diagnostics, the specificity, Youden index, positive likelihood rate and coincidence of IHA-B were the highest.


CONCLUSIONS
Kato-Katz method is more stable and effective than nylon bag sedimentation/hatching method in medium and heavily endemic areas of schistosomiasis japonica. The sensitivity and specificity of these four diagnosis kits are lower than 90%.
National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Shanghai 200025, China.
Jing
J
Xu
Nian-gao
NG
Chen
Ting
T
Feng
En-mu
EM
Wang
Xiao-hua
XH
Wu
Hong-gen
HG
Chen
Tian-ping
TP
Wang
Xiao-nong
XN
Zhou
Jiang
J
Zheng
D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood; D002648:Child; D002681:China / Q000453:epidemiology; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005243:Feces / Q000469:parasitology; D006386:Hemagglutination Tests / Q000379:methods; D006801:Humans; D007118:Immunoassay / Q000379:methods; D008297:Male; D008875:Middle Aged; D010270:Parasite Egg Count; D015203:Reproducibility of Results; D012549:Schistosoma japonicum / Q000276:immunology / Q000302:isolation & purification*; D012554:Schistosomiasis japonica / Q000175:diagnosis* / Q000453:epidemiology; D012680:Sensitivity and Specificity; D055815:Young Adult
D000909:Antibodies, Helminth