[Study on the dynamics of IgG antibody in 311 patients with severe acute respiratory syndrome].

Fan, Bao-xing; Xie, Li-xin; Chen, Liang-an; Chen, Wei-jun; Wen, Jie; Liu, You-ning

OBJECTIVE To detect the level and dynamic change of severe acute respiratory syndrome (SARS)-coronavirus-specific IgG antibody in conavalescent SARS patients, and to provide information for prevention and vaccine development. METHODS IgG antibody against coronavirus was detected by ELISA in the blood of 311 convalescent SARS patients for every 2 - 4 weeks. Stata 7.0 statistics software was used to analyse the results. RESULTS IgG antibody was detected positive on each testing of all the convalescent patients and its peak appeared 35 days after recovery. IgG antibody level showed a 35.8% decrease within one year. CONCLUSION Data showed that all the SARS convalescent patients had generated high level of specific IgG antibody against coronavirus in the early stage of recovery, but the antibody level declined along with the progress of convalescence, suggesting that the detection of the IgG antibody should go on until it disappeared.