Enterovirus 71 Antibody Level Of Children In Guangzhou

Enterovirus 71 belongs to Picornaradae and is a members of Enterovirus. HFMD caused by EV71 occurred in infants and children under 5 years old. Children under 5 years old who infected EV71 easily lead to fever and rash on hand, foot, mouth and other parts, these are the common symptoms of hand, foot and mouth disease. To severe cases with neurological and cardiopulmonary complications, children with severe EV71 infection with high mortality and poor prognosis. EV71 infection can also cause local or a wider range of hand, foot and mouth disease outbreaks. Therefore, the Ministry of Health listed it as a class C infectious diseases in May 2, 2008. In the study, we researched the biological characteristics of EV71. Based on the research, a assay which employs ELISA for detecting EV71-IgG was developed. And this assay was used to survey enterovirus 71 antibodies (EV71-IgG) levels to children in Guangzhou area. In this study, enterovirus 71 virus was isolated from throat swaband sample and was identified by gene sequencing to subgenogroup C4. This viral was coated as a antigen in ELISA. The coating concentration and the HRP anti-human IgG antibody concentration were determined by the checkerboard titration. According to the OD value of negative serum samples determined cut-off value. Neutralization Test was used to screen out 20 EV71 positive serums, 100 EV71 negative serums and 5 CoxA16 positive serums. These serums were detected EV71-IgG. The results showed that the EV71-IgG ELISA reaction system can detected out all positive serums, 92% EV71 negative serums, and have no cross with CoxA16 positive serums. Therefore, the EV71-IgG reaction system can be applied to detect EV71-IgG antibody in the serum. 819 sera were measured for EV71-IgG by ELISA. All sera samples came from Health Department of Guangzhou Women and Children's Medical Center. We analysis of all serum the level of EV71-IgG in age and gender differences. The result indicate: In 819 serum samples, the highest EV71-IgG positive rate of the 0 to 1 age group was 60.00%, this rate declined after the age of 1. The groups of age 2 and age 5 to 14 remained at a lower level. X2 test analysis showed that in age group 0 to 1's EV71-IgG positive rate was significantly higher than other groups (X2, respectively 11. 65, 52. 49, 26. 07, 48. 58, 37.35, P <0.05); among the age group of 2 ~ 3 years old, 3 to 4 years old, 4 to 5 years, and 5 to14 years old, the EV71-IgG positive rate's differences were no statistically significant. Examine the binomial distribution analysis showed that the positive rate of all age groups there was no gender difference between the (positive rate of six age groups of male and femal respectively compared u-1.32, 0.90,1.24,0.90, -0.034,1.26, P> 0.05 .)The study above was a part of the works including serum neutralization test, vaccine research.