Early assessment of the safety and immunogenicity of a third dose (booster) of COVID-19 immunization in Chinese adults / 医学前沿

Inducing durable and effective immunity against severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) via vaccination is essential to combat the current pandemic of coronavirus disease 2019 (COVID-19). It has been noticed that the strength of anti-COVID-19 vaccination-induced immunity fades over time, which calls for an additional vaccination regime, as known as booster immunization, to restore immunity among previously vaccinated populations. Here we report a pilot open-label trial of a third dose of BBIBP-CorV, an inactivated SARS-CoV-2 vaccine (Vero cell), on 136 participants aged between 18 to 63 years. Safety and immunogenicity in terms of neutralizing antibody titers and cytokine/chemokine responses were analyzed as the main endpoint until day 28. While systemic reactogenicity was either absent or mild, SARS-CoV-2-specific neutralizing antibody titers rapidly arose in all participants within 4 weeks, surpassing the peak antibody titers elicited by the initial two-dose immunization regime. Broad increases of cellular immunity-associated cytokines and chemokines were also detected in the majority of participants after the third vaccination. Furthermore, in an exploratory study, a newly developed recombinant protein vaccine, NVSI-06-08 (CHO Cells), was found to be safe and even more effective than BBIBP-CorV in eliciting humoral immune responses in BBIBP-CorV-primed individuals. Together, these results indicate that a third immunization schedule with either homologous or heterologous vaccine showed favorable safety profiles and restored potent SARS-CoV-2-specific immunity, providing support for further trials of booster vaccination in larger populations.

Expert recommendations on booster immunization strategies of 2019-nCoV vaccines / 中华临床感染病杂志

Since the end of 2019, the COVID-19 caused by 2019-nCoV has emerged and the pandemic ravaged the world, which seriously threatens global public health security and economic development. 2019-nCoV vaccine is an effective weapon to combat the viral infection, however, studies have shown that vaccine-induced immune protection decreases over time, coupled with some novel and immune escape variants continual emerging. Therefore, it is urgent to complete booster immunization to improve protection. At present, 2019-nCoV vaccines based on a variety of technical platforms have been approved and available in China. Therefore, we developed this sequential vaccination strategy guide to provide documentation guidance for the prevention and control of the epidemic caused by 2019-nCoV and its variant strains.

Quantitative analysis of immune responses to hepatitis B vaccination in children in Hangzhou and discussion on age of booster immunization / 中华实用儿科临床杂志

Objective:To investigate the appropriate age for booster doses of hepatitis B vaccine in children aged 0-14.Methods:Retrospective study.A total of 3 118 children aged 0-14 years who underwent quantitative serological marker testing for hepatitis B virus at the Affiliated Hospital of Hangzhou Normal University from January 2015 to October 2021 were recruited in this analysis.There were 1 702 males and 1 416 females, with a male to female ratio of 1.20∶1.00.Children were divided into 15 groups according to their age, and the classifying interval was 1 year.The hepatitis B virus surface antibody (Anti-HBs) titer was quantified by chemiluminescent microparticle immunoassay.The Anti-HBs positivity rates and hepatitis B immune response among groups of different sexes and age were compared by the chi- square test and rank- sum test, respectively. Results:A total of 3 118 children were investigated.The titer and effective response rate of Anti-HBs decreased gradually with age.The difference in the titer and effective response rate of Anti-HBs was statistically significant among groups of different age (all P<0.01), but not significant between males and females (all P>0.05). The median titer of Anti-HBs in children aged above 3 years was 58.49 IU/L(0-1 001.00 IU/L). About 59.1% (1 477/2 497 cases) of children aged 3 years and above had no immune response or low immune response (i.e., the titer of Anti-HBs was below 100 IU/L). Conclusions:The immune protective effect of the hepatitis B vaccine decreases year by year in children who have received the standardized vaccine, and the vaccine has poor protective effect on most children aged 3 years and above.Therefore, booster dose vaccination for preventing hepatitis B is necessary for children aged 3 and above.

The immune effects of hepatitis B on children boosted with hepatitis A and B combined vaccine / 预防医学

Objective To observe the concentration of the anti-HBs of children boosted with hepatitis A and B combined vaccine for 3 dosages, and to provide the basis for the implementation of hepatitis B booster immunization. Methods In September 2009 in Yuhuan by employing the cluster sampling method, 123 children, ranging from 6 to 9 years old, who had completed the basic immunization by 0-1-6 procedure without hepatitis B vaccine boosted and without anti-HBs were selected. In the year of 2011 (after 1 year of inoculation) and 2015 (5 years after inoculation), the venous blood samples were collected to determine the concentration of anti-HBs. Results Boosted with hepatitis A and B combined vaccine for 3 times, the anti-HBs of 102 subjects was tested in the next year, of which the anti-HBs of 82 subjects was detected again in the later 5 years. The results suggested that the positive rates of antibody enhanced were 92.16% after 1 year and 78.05% after 5 years, respectively. The average concentration of anti-HBs of these 82 subjects was 2.95 mIU/mL before inoculation, 141.76 mIU/mL one year later and 72.13 mIU/mL 5 years later and there was statistically significant difference among them (P <0.05) . The difference was not statistically significant between subjects with different years of birth (P>0.05) . Moreover, the interaction was existed between the year of blood detection and year of birth (P <0.05) . Conclusion To children aged 6-9 years old whose anti-HBs were negative after the primary immunization of hepatitis B, booster immunization with 3 dosages of hepatitis A and B combined vaccine shows good immune effect against hepatitis B virus.

Efficacy and safety evaluation on 10 μg Hansenula recombinant hepatitis B vaccine booster for school-age children / 上海预防医学

Objective] To assess the safety and immunogenicity of booster vaccination 10 μg of recombinant Hansenula hepatitis B vaccine in school-age children , and to provide scientific basis for the development of hepatitis B immunization strategies . [ Methods] A total of 2 101 children were selected as the safety study object and were inoculated with three injections of 10 μg Hansenula hepatitis B vaccine for observation of the incidence of abnormal reaction .Among them 404 schoolchildren were observed for immune effects.And comparison was made in the difference of antibody titers and antibody positive rate before and after immunization . [ Results] Of the 2 101 children, 85 cases of adverse reactions occurred and the incidence rate was 4.05%.Of the 85 cases, 84 had slight reactions , one with moderate reactions and none with severe reactions .After vaccination , the positive rate of protective antibodies increased to 100.00%, and antibody titers rose from 2.55 IU/L to 5 051.90 IU/L, the difference being statistically significant (Z =12.51, P =0.00). [Conclusion] Hansenula hepatitis B vaccine used for booster immunization in schoolchildren is of good security and fine immune effect .

An observation on effect of different dosage booster immunization of hepatitis Bvaccine / 预防医学

Objective To evaluate the effect on the booster immunization of different dosage of hepatitis B vaccine among children and to provide suggestions for booster immunization.Methods Children aged 5 -1 4 years old were randomly selected who had received the primary immunization of hepatitis B vaccine under 1 year old but had not received the booster immunization in Yuhuan county.A total of 547 children received 5 μg hepatitis A and B combined vaccine boost immunization and 688 children received 1 0 μg hepatitis B vaccine boost immunization in 2009.The anti -HBs levels before and after the boost immunization were detected.Results The anti -HBs positive rates of children received 5 μg and 1 0 μg vaccine boost immunization were 97.81 % and 96.08% respectively and the positive rates in the antibody negative children were 94.78% and 93.62% respectively.While the Geometric Mean Titer (GMT) of anti -HBs were 1 433.1 8 mIU /mL and 21 1 1 .43 mIU /mL respectively,which were both significantly higher than those before the boost immunization (P <0.001 ).The increase of GMT of children received 1 0 μg hepatitis B vaccine was significantly higher than that of children received 5 μg hepatitis A and B combined vaccine (P <0.05).Conclusion Both dosages of hepatitis B vaccine booster immunization are effective for children aged 5 -1 4 years old and 1 0 μg hepatitis B vaccine boost immunization has the better effect.

The long-term efficacy of recombinant hepatitis B vaccines for children / 预防医学

Objective To observe long-term efficacy of recombinant hepatitis B vaccines for children received fundamental immunization or booster dose. Methods 493 school students from Deqing county with complete information of immunization history were investigated and their serological markers were detected. 430 students received booster dose vaccines at 3-11 years old and were defined as booster group while the remaining 63 students were defined as fundamental group. Results All vaccines the 493 students received for fundamental immunization were recombinant. Compared with fundamental group(57. 14%),booster group had significantly higher Anti-HBs positive rate of 91. 40%(P<0. 01). And the Anti-HBs positive rate had a high level of 94. 99% when 0-5 years after booster immunization while it declined to 64. 71% after 8-15 years and showed no significant difference compared with fundamental group. Conclusion Anti-HBs level and anti -HBs positive rate can significantly increase for short periods after booster immunization,and may decline considerably for long-term. Immunologic amnesia rate is low when 3 -11 years after fundamental immunization among infants.

Short-term and long-term antibody response by mice after immunization against Neisseria meningitidis B or diphtheria toxoid

Serogroup B Neisseria meningitidis (MenB) is a major cause of invasive disease in early childhood worldwide. The only MenB vaccine available in Brazil was produced in Cuba and has shown unsatisfactory efficacy when used to immunize millions of children in Brazil. In the present study, we compared the specific functional antibody responses evoked by the Cuban MenB vaccine with a standard vaccine against diphtheria (DTP: diphtheria, tetanus, pertussis) after primary immunization and boosting of mice. The peak of bactericidal and opsonic antibody titers to MenB and of neutralizing antibodies to diphtheria toxoid (DT) was reached after triple immunization with the MenB vaccine or DTP vaccine, respectively. However, 4 months after immunization, protective DT antibody levels were present in all DTP-vaccinated mice but in only 20% of the mice immunized against MenB. After 6 months of primary immunization, about 70% of animals still had protective neutralizing DT antibodies, but none had significant bactericidal antibodies to MenB. The booster doses of DTP or MenB vaccines produced a significant antibody recall response, suggesting that both vaccines were able to generate and maintain memory B cells during the period studied (6 months post-triple immunization). Therefore, due to the short duration of serological memory induced by the MenB vaccine (VA-MENGOC-BC® vaccine), its use should be restricted to outbreaks of meningococcal disease.

Evaluation on the efficacy of recombinant hepatitis B vaccine booster immunization in 2789 children aged oner 10 years / 中华流行病学杂志

Objective To study the efficiency of booster immunization with different recombinant hepatitis B vaccines.Methods 2789 children aged over 10 years who had completed the basic immunization of hepatitis B vaccine under 1 year old were selected.All the sampled children were classified into four groups (A,B,C and D) and immunized with different hepatitis B vaccines produced by different campanies respectively.Before booster immunization,their blood plasma specimens were detected for hepatitis B virus (HBV) surface antigen (HBsAg),antibodies to HBV surface antigen (anti-HBs) and antibodies to HBV core antigen (anti-HBc) by chemiluminescence.In each group,the anti-HBs positive children were immunized with one dosage and anti-HBs negative children were immunized three dosages of the same vaccine.Their blood specimens were collected again after 1 month,and detected for anti-HBs.Results The anti-HBs positive rates of A,B,C and D group were 36.43%,37.59%,42.91% and 46.46% respectively before immunization while 89.20%,91.52%,90.96% and 85.45% respectively after immunization with one dosage,99.12%,99.47%,98.87% and 98.85% respectively after immunization with three dosages.The differences of anti-HBs positive rates in the four respective groups showed statistical significances between any two rates of pre-immunization,post-immunization with one dosage and post- immunization with three dosages (all P＜0.05).The anti-HBs positive conversion rates of four groups were 83.01%,86.41%,84.16% and 72.82% respectively after immunization with one dosage.The anti-HBs positive conversion rate of four groups were 98.62%,99.16%,98.03% and 97.84% respectively after immunization with three dosages and the difference of positive conversion rates in each group showed statistical significances between booster immunization with one dosage and booster immunization with three dosages.The average GMTs in anti-HBs positive children in the four groups were 2853.21,6254.23,3581.40 and 3021.32 mIU/ml respectively after immunization with one dosage.The average GMTs of anti-HBs negative children in the four groups were 273.08,648.52,387.87 and 245.36 mIU/ml respectively after immunization with one dosage,and were 632.30,2341.14,563.97 and 394.08 mIU/ml respectively after immunization with three dosages.Conclusion Our data showed that it would be suitable to anyone to use the four vaccines for anti-HBs positive children aged over 10 years with one dosage and for anti-HBs negative children aged over 10 years with three dosage booster immunization.

Booster immunization with paternal lymphocytes to recurrent spontaneous abortors of less reaction to paternal lymphocyte immunization / 中国免疫学杂志

Objective:To evaluate curative impact of booster immunization with paternal lymphocytes on recurrent spontaneous abortors(RSA)with less reaction of primary patermal lymphocyte immunization.Methods:RSA patients with insufficient materno-fetal immuno-recognition were selected by flow cytometry of blocking antibody analysis and immunized with either induced paternal lymphocytes pretreated by IFN-? in vitro to those of anti-CD3-BE and anti-CD4-BE Ab lower than 0% or direct intradermal vaccination with their paternal lymphocytes without IFN-? pretreatment to those of anti-CD3-BE Ab beyond 0%.Reassessment of blocking antibodies was performed at the end of the second immnunization course.Results:Levels of blocking antibodies were significantly raised after the secondary booster immunization in RSA with insufficient materno-fetal immnuno-recognition whose blocking antibodies continuously decreased after being treated by the primary paternal lymphocyte immunization.No improvement of parameters was observed except the blocking effect in patients receiving secondary direct intradermal vaccination treatment.Conclusion:It is necessary for the RSA with insufficient materno-fetal immuno-recognition to experience secondary booster immunization preferably with paternal lymphocytes pretreated by IFN-? in vitro.