ABSTRACT
The practicable and effective methods for residual risk assessment on transfusion-transmitted disease was to establish the mathematic models. Based on the characteristics of the repeat donors which donated their blood on a regular base, a model of sero-conversion during the interval of donations was established to assess the incidence of the repeat donors. Based on the characteristics of the prevalence in the population, a model of ‘prevalence increased with the age of the donor' was established to assess the incidence of those first-time donors. And based on the impact of the windows period through blood screening program, a model of residual risk associated with the incidence and the length of the windows period was established to assess the residual risk of blood transfusion. In this paper, above said 3 kinds of mathematic models were jointly applied to assess the residual risk of hepatitis C virus (HCV) which was transmitted through blood transfusion in Shanghai,based on data from the routine blood collection and screening program. All the anti-HCV unqualified blood donations were confirmed before assessment. Results showed that the residual risk of HCV transmitted through blood transfusion during Jan. 1st,2007 to Dec. 31st,2008 in Shanghai was 1∶101 000. Data showed that the results of residual risk assessment with mathematic models was valuable. The residual risk of transfusion-transmitted HCV in Shanghai was at a safe level, according to the results in this paper.
ABSTRACT
OBJECTIVE To compare two different procedures of blood donation in volunteer donors,which lead to different discard rates of blood,different donation reaction rates and the satisfaction of the donor agency,so as to seek the better procedure bringing less discard of blood and more convenience for the military donor agency and blood center. METHODS In group A,3 667 donors blood was collected before the tests and retests for transfusion transmitted diseases(TTD) were done.While in group B,4 185 donors were taken blood samples for pre-donation test.The blood collection was performed 4 hours later. RESULTS In group A,3 652 units of blood were collected,of which 69 units were discarded on account of positive results in test and retest.Meanwhile,in group B 3 718 units of blood were collected from the donors who passed the pre-donation test for TTD.As a result,34 units of blood were discarded because of the positive results in retest.The discard rates of blood were 1.89% and 0.91% while the donation reaction rates were 2.22% and 3.98%,respectively.in two procedures.The discard rates of blood in group A were higher than those in group B.But the donation reaction rate in group B was higher than that in group A. CONCLUSIONS The discard rate of blood in the procedure collecting before test is higher than that in the procedure testing before collection.But the donation reaction rate is low and the waiting period for donation is short in the former procedure,which is suitable for low TTD infections population of military agencies.
ABSTRACT
Objective To strengthen the control of blood quality, ensure the safety of blood for clinical use and effectively contain the occurrence of transfusion transmitted disease. Methods Using the method of random sample survey, appraisal was made once again of the blood for clinical use in the blood stations of 14 cities(regions) of Hunan Province in 1997～2001, blood that had passed reexamination by relevant blood collecting and supplying institutions. The appraisal, conducted in the proportion of 10% of the yearly use of blood, focused on 5 indexes, including HBsAg, Anti HCV, Anti HIV, RPR, and ALT. Results 6 211 blood samples were checked, with the total positive rate being 7.89‰. Among theses, the positive rate of samples sent for testing was 7.78‰, the positive rate of samples collected and tested on the spot was 9.35‰, the positive rate of HBsAg was 2.59‰, the positive rate of Anti HCV was 3.86‰, the positive rate of Anti HIV after primary screening was 0.64‰(ascertained to be negative through Western Blot testing), the rate of ALT≥25 IU was 0.81‰, and the testing of syphilis was all negative. Conclusion Serious problems remain to be solved with regard to the safety of blood for clinical use.