RESUMEN
Objective By studying the change of the special antibodies titer IgG, IgM and nucleocaspid to SARS corona virus in family clustering cases , searching and testing the special antibody to SARS corona virus in the patients kinfolks Method Testing special antibody titer to SARS corona virus of 14 patients from 5 different families and their 10 kinfolks continuously by IFA and antigen capturing ELISA methods, taken samples in the 7 th , 14 th , 30 th , 60 th , 120 th , 180 th , 210 th ,270 th ,360 th day after SARS patients infected by SARS corona virus, dilute them, and then measure titers of three kinds of antibodies ResultsDuring the testing of IgG antibody titer of the 14 SARS patients by IFA method, in the 120 th day, the average titer is up the highest value, it is 1/1 120; in the 180 th day, the average titer begins to descend, it is 1/262 in the 360 th day, the average titer is 1/71 During the testing of IgM titer, the average titer is 1/32, it is obviously lower than it in IgG testing; the IgM titer of the most SARS patients are disappear after 120 days The average value of nucleocaspid antibody titer is lower than it in IgG antibody But there are some differences in 5 cases While IgG antibody titer begins to descend in the 180th day, nucleocaspid antibody titer begins to ascend obviously, it is up to 1/790 210 th day begins to descend In the meantime, we have tested special antibody to SARS corona virus of their 10 kinfolks (include 2 children) who have contacted with SARS patients closely The samples are taken in the 14 th , 30 th , 60 th day, and all the special IgG, IgM and nucleocaspid antibody to SARS corona virus are negative ConclusionBy testing the special IgG antibody to SARS corona virus of the 14 family clustering cases ,we find the special IgG antibody titer of the SARS patient is higher, and it can remain for a long time As for the nucleocaspid antibody titer of some SARS patients ascend obviously after 180days, we think that it provide useful information for vaccine development and it is necessary for us to study more in the clinic There is no special blood serum antibody to SARS corona virus in their 10 kinfolks of the SARS patients
RESUMEN
Objective To detect IgG and IgM antibodies in the sera of SARS patients, in order to find the possible causative association between new coronavirus and SARS; to compare IgG and IgM antibody titers of acute phase with those of convalescent phase, in order to find specific serological reaction of SARS virus and its clinical significance. Methods Clinical specimens of SARS patients in 4 hospitals of Guangdong Province were collected and then detected by IFA and ELISA. The specificity and cross-reaction of each specimen for confirming the new coronavirus were evaluated. Results One hundred and seventeen of 130 clinically diagnosed SARS patients showed viral specific serological reaction, with the positive rate of 90%. The IgG titer increased significantly 10 days after the onset of infection and reached a higher level (above 320) 15 days later, while IgG titer reached the highest level on the 20 th-30 th day. The specific antibodies were negative in all 119 individuals with close contact with patients and 100 normal controls. Conclusion Viral specific IgG antibody was detected in the sera of SARS patients, confirming that the patients were infected by the virus; persistent high titer of IgG antibody in the sera of convalescent patients might probably be a protective mechanism in general population.