ABSTRACT
Objective@#To investigate the serum levels of anti-measles antibody among residents in Zhejiang Province in 2018, so as to provide insights into measles control.@*Methods@#Permanent residents aged 0 to 59 years were recruited using the stratified multistage random sampling method in Zhejiang Province in 2018, and subjects' demographic features, medical history of measles and history of immunization with measles-containing vaccine (MCV) were collected using a questionnaire survey. The serum level of anti-measles IgG antibody was detected, and the geometric mean concentration (GMC) of anti-measles IgG antibody was estimated. The seroprevalence, protective rate and GMC of anti-measles IgG antibody were compared among residents at different age groups and regions.@*Results@#A total of 4 189 residents were enrolled, including 1 939 males and 2 250 females, with a male to female ratio of 1∶1.16. There were 3 858 residents positive for anti-measles IgG antibody, with seroprevalence of 92.10%, and there were 2 072 residents with protective antibodies against measles, with a protective rate of 49.46%. The median GMC of anti-measles IgG antibody was 798.33 (interquartile range, 1 024.06) mIU/mL, and the protective rate of anti-measles IgG antibody appeared a tendency towards a decline with age ( χ2trend=18.067, P<0.001 ). There were significant differences in the seroprevalence ( χ2=45.090, P<0.001 ), protective rate ( χ2=57.432, P<0.001 ) and GMC of anti-measles IgG antibody (χ2=88.624, P<0.001 ) among residents at different regions, with the lowest seroprevalence of anti-measles IgG antibody in Ningbo City ( 85.19% ), the lowest antibody-protective rate (38.98%) and the lowest GMC [632.89 ( 909.04 ) mIU/mL] in Zhoushan City, the highest seroprevalence ( 95.16% ), antibody-protective rate (58.48%) and GMC [1 035.84 ( 1 301.77 ) mIU/mL] in Huzhou City.@*Conclusions@# The protective rate of anti-measles antibody was low and appeared a tendency towards a decline among residents in Zhejiang Province in 2018. There was a region-specific serum level of anti-measles antibody in Zhejiang Province in 2018.
ABSTRACT
Objective To evaluate the protective rate and the variation of HFRS-IgG on hemorrhagical fever with renal syndrome (HFRS) vaccine.Methods Cluster,random sampling and cross-sectional study were used to assess the protective rate of HFRS vaccination.Level of HFRS-IgG was detected with ELISA in epidemic and non-epidemic areas of HFRS.Results Curve equation was obtained as Yprocective rate=(0.863+0.283/Xvaccination term) × 100％ by protective rate with vaccination term.Protective rates showed a reducing trend,90％ after 7-8 years of vaccination,88％ after 10 years,and 94％ on average.Absorbance (A) value of HFRS-IgG was 4 times higher in persons with vaccination than those without,in the epidemic area.Higher antibody level could be obtained after primary vaccination,but the level of antibody had a 50％ reduction after 5-10 years of vaccination,and a 60％ reduction after 10 years of vaccination.Conclusion HFRS antibody had a 50％ reduction after 5-10 years of vaccination.The protective rate of HFRS vaccination had a 90％ loss,after 7-8 years of vaccination.Booster dose was necessary after 7 years of vaccination.
ABSTRACT
ObjectiveTo assess the efficacy and the immunological memory of plasma-derived hepatitis B vac- cine 11 years after the initial inoculation. Methods A randomized, double-blind and placebo-controlled trial design was used. Results The immunogenicity and protection rate of the vaccine were good 1 1 years after vaccination, how- ever, from 9 to 11 years after vaccination, the perscn year HBV infection rate showed no noticeable difference be- tween the vaccine group and placebo-controls. Furthermore, the immunological memory remained 11 years after in- oculation, but was significantly lower than that observed in the past 10 years. Conclusion Vaccine protection wanes over the years. More information is needed to define the appropriate time for vaccine booster doses.