Comparison of humoral immune response in heterologous and homologous COVID-19 booster vaccine groups using CoronaVac and mRNA-based BNT162b2 vaccines

ABSTRACT Background: Heterologous COVID-19 booster vaccination is an alternative strategy to homologous vaccination, especially in developing countries, due to shortages, delays, or unequal distribution of COVID-19 vaccines. We compared cohorts vaccinated with different vaccine combinations to investigate whether a heterologous booster dose of mRNA-based BNT162b2 vaccine boosts the immune response in individuals primed with the CoronaVac vaccine. Methods: Anti-RBD IgG is generally measured 4 weeks after primary immunization and 4 weeks after booster vaccination. Data on anti-receptor-binding domain (anti-RBD) IgG antibody titers and clinical characteristics were provided by infection control units. Results: The highest median anti-RBD IgG antibody titers (14589 AU/mL) after primary immunization was observed in the group vaccinated with two doses of BNT162b2 vaccine. Antibody titers were lower 4 months or more after the second CoronaVac vaccine dose in CoronaVac recipients with or without previous COVID-19. In the homologous COVID-19 booster vaccine group (primed with two doses of CoronaVac 4 weeks apart and a single booster dose of CoronaVac) the median anti-RBD titers decreased from 1025 to 242 AU/mL before the booster dose. In the heterologous group (primed with two doses of CoronaVac 4 weeks apart and a single booster dose of BNT162b2), the median anti-RBD titer increased to 31624 AU/mL, a 132-fold increase, 16 days after the booster dose. Conclusions: After the second dose of CoronaVac, protective neutralizing antibody levels decrease over time, and a booster dose is required. Heterologous COVID-19 booster vaccination with BNT162b2 is effective at boosting neutralizing antibody levels.

COVID Management Strategy for Third Wave / Omicron Variant in India

COVID-19, the worst Pandemic of this decade caused significant morbidity and mortality in the past 3 years and still continue to hit the human kind with it’s evil skills. After the first and second COVID-19 wave the third wave has emerged with new variants and with high transmission rate and reduced efficiency of treatments and vaccines. The main treatment strategy remain same as symptomatic and supportive treatments. Oxygen therapy, Steroid, Antivirals and some repurposed drugs like Ivermectin and newer drugs including monoclonal antibodies are used in this fight against COVID-19. Ivermectin is being the game changer in many states of India, they kept this medicine in their new treatment protocol also. Vaccination including additional Booster/Precautionary Dose along with the COVID appropriate behaviours, if we are able to maintain Physical distance, Wear mask properly, Wash our hands and Prevent crowd from gathering then we will not allow the virus to spread and prevent the emergence of another wave

Generation of neutralizing antibodies against Omicron, Gamma and Delta SARS-CoV-2 variants following CoronaVac vaccination

ABSTRACT Vaccination is a fundamental tool to prevent SARS-CoV-2 infection and to limit the COVID-19 pandemic. The emergence of SARS-CoV-2 variants with multiple mutations has raised serious concerns about the ability of neutralizing antibody responses elicited by prior vaccination to effectively combat these variants. The neutralizing capacity against the Gamma, Delta and Omicron variants of sera from individuals immunized with the CoronaVac vaccine remains incompletely determined. The present study evaluated 41 health care workers at the Faculdade de Medicina of the Universidade de Sao Paulo, in Sao Paulo, Brazil, naive to previous SARS- CoV-2 infection, who were vaccinated with two doses of the CoronaVac SARS-CoV-2 vaccine 28 days apart. Neutralizing antibody levels against the Gamma, Delta, and Omicron variants were measured at 32 and 186 days after the second vaccination. We also measured neutralizing antibodies against Omicron in 34 of these individuals following a subsequent booster immunization with the Pfizer vaccine. Quantification of neutralizing antibodies was performed using the Cytopathic Effect-based Virus Neutralization test. Neutralization antibody activity against the Gamma, Delta and Omicron variants was observed in 78.0%, 65.9% and 58.5% of serum samples, respectively, obtained at a mean of 32 days after the second immunization. This decreased to 17.1%, 24.4% and 2.4% of sera having activity against Delta, Gamma and Omicron, respectively, at 186 days post-vaccination. The median neutralizing antibody titers at 32 days were 1:40, 1:20 and 1:20 against Gamma, Delta and Omicron, respectively, and decreased to an undetectable median level against all variants at the later time. A booster immunization with the Pfizer vaccine elicited neutralizing antibodies against Omicron in 85% of subjects tested 60 days after vaccination. We conclude that two doses of the CoronaVac vaccine results in limited protection of short duration against the Gamma, Delta and Omicron SARS-CoV-2 variants. A booster dose with the Pfizer vaccine induced antibody neutralizing activity against Omicron in most patients which was measurable 60 days after the booster.

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.

Cross-neutralization of antibodies induced by inactivated SARS-CoV-2 vaccine against Beta and Delta variants / 中华微生物学和免疫学杂志

Objective:To evaluate the in vitro cross-neutralization of serum antibodies in human and mice immunized with inactivated SARS-CoV-2 vaccine against Delta and Beta variants. Methods:Human serum samples after a second and a third dose of inactivated SARS-CoV-2 vaccine and mouse serum samples after a two-dose vaccination were collected. The neutralizing antibodies in the samples against SARS-CoV-2 strains of prototype, Delta and Beta variants were detected using micro-neutralization assay in biosafety level Ⅲ laboratory. The seroconversion rates and geometric mean titers (GMTs) of antibodies were calculated.Results:The seroconversion rates of antibodies in human serum samples against different SARS-CoV-2 strains were all above 95%. After two-dose vaccination, the GMTs of neutralizing antibodies against the prototype, Delta and Beta strains were 109, 41 and 15, respectively. The GMTs decreased by 2.7 folds and 7.3 folds for the Delta and Beta variants as compared with the prototype strain. After the booster vaccination, the GMTs of neutralizing antibodies against the prototype, Delta and Beta strains were 446, 190 and 86, respectively. The GMTs of neutralizing antibodies against Delta and Beta variants decreased by 2.3 folds and 5.2 folds as compared with that against the prototype strain. The seroconversion rates of antibodies against different SARS-CoV-2 strains in mouse serum samples were all 100%. The GMTs of neutralizing antibodies against the prototype, Delta and Beta strains were 2 037, 862 and 408, respectively. The GMTs decreased by 2.4 folds and 5.0 folds for the Delta and Beta variants.Conclusions:Inactivated SARS-CoV-2 vaccine could induce a certain level of neutralizing antibodies against Delta and Beta variants in both human and mouse models. Moreover, a third dose of vaccine induced higher levels of neutralizing antibodies against Delta and Beta variants in human. This study provided valuable data for the clinical application and protective evaluation of the inactivated SARS-CoV-2 vaccine.

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.

The need to vaccinate against COVID-19

@#Globally, now in the third year of the pandemic, COVID-19 deaths have exceeded more than 6 million. As new subvariants emerge and spread, vaccines work to limit the worst of COVID-19 and continue to be important. Restraints are lifted, and COVID-19 may be seen as done for some, but COVID-19 is not yet done with others, no matter how badly everyone wants it to end. The SARS- CoV-2 pandemic has caused considerable morbidity and mortality worldwide. The protection provided by vaccines and booster doses offer a method of mitigating severe clinical outcomes and mortality. As debates over additional booster shots for COVID-19 intensify, many researchers are looking to the universal coronavirus vaccine model as a guide for managing future variants of SARS-CoV-2 and preempt the next COVID-19 surge.

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.

Seroprevalence of anti-HBs antibodies and the need for booster vaccination in children under 5 years of age born to HBsAg-negative mothers

Objective: To determine the proportion of HBV surface antigen (anti-HBs) antibody positive children under five years of age born to HBsAg-negative mothers and to analyze the possible related factors following implementation of a hepatitis B vaccination program for infants in Indonesia 22 years ago. Methods: Blood samples were taken from children under five years of age born to HBsAg-negative mothers who have completed primary vaccination series. Anti-HBs antibodies were determined by using rapid test. Data of age, gender, nutritional status, vaccination timing or vaccination compliance, and booster vaccination were collected from vaccination card. Results: Ninety children were enrolled, consisting of 47 females and 43 males with a mean age of 2.3 years. Twenty two (24.4%) children received booster vaccine between 18 and 24 months and 55 (61.1%) were anti-HBs positive. Among factors of age, gender, nutritional status, compliance to vaccination and booster vaccine, only administration of booster vaccine was significantly associated with anti-HBs status (OR 5.45, 95% CI 1.45, 20.52). Children who received booster vaccine at age of 18-24 months were 5.45 times more likely to be anti-HBs positive than that of children who did not receive booster vaccine. Conclusions: Booster vaccine rate is low among children under 5 years of age but is associated with anti-HBs positivity. Booster vaccination may be required to improve anti-HBs seropositivity.

Effect of sodium hyaluronate compound solution injected with booster in treatment of neck wrinkles / 中华医学美学美容杂志

Objective:To observe the clinical effect of booster injection of sodium hyaluronate compound solution in the treatment of neck wrinkles.Methods:From April 2020 to January 2021, Chongqing Yihengyan Medical Cosmetology Clinic recruited 50 female patients with cervical stripes, aged 32 to 56 years, with an average of 42.8 years, and divided into booster group and control group, 25 cases in each group. Patients in the booster group were injected with sodium hyaluronate composite solution to fill neck wrinkles using an automatic subcutaneous electronic syringe control booster device, while patients in the control group were injected manually with syringes. Efficacy evaluation included pain degree during injection, difficulty of injection, swelling and bruising degree after injection, complications and treatment satisfaction.Results:The pain degree ( F=0.228, P<0.01), difficulty of injection ( t=2.741, P<0.05) and the complication after injection for uneven swelling (χ 2=4.878, P<0.05), scleroma (χ 2=5.882, P<0.05), ecchymosis degree (χ 2=5.333, P<0.05) inbooster group were lower than those of control group, and the treatment satisfactory score was higher than that in control group. Conclusions:The application of booster can significantly improve the therapeutic effect of injecting sodium hyaluronate compound solution to fill the neck wrinkles, reduce complications, increase the patient＇s comfort, and ease the operation difficulty of the injector, which is worthy of clinical promotion.

Evaluation of immunity rate against hepatitis B among workers in National Center for Transfusion Medicine / Эрүүл мэндийн лаборатори

Background@#Healthcare works are high risk of infection through occupational exposure that contact with blood and other body fluids, including infected person, uses needles, syringes, equipment or exposures to sharp instruments. The World Health Organization (WHO) estimates, approximately 66,000 health workers are infected with the hepatitis B virus (HBV) and 200-5000 workers arc infected with human immunodeficiency virus (HIV) each year due to carelessness. HBV infection is a global health problem that remains to preventive. Hepatitis B can be prevented by vaccines that are safe, available and effective. In our country, which has a high prevalence of hepatitis B virus infection, it has been concluded that the coverage of hepatitis B vaccination and the level of immunity of health workers are insufficient.@*Aim@#To evaluate post vaccination immunity against HBV in the staff of National center for transfusion medicine @*Methods@#63 workers with negative surface antigen of hepatitis B (HBsAg) and absent anamnesis of infection were selected for this study. In 2019 and 2020 all 63 workers were evaluated post vaccination immunity against HBV. Analysis done by Sysmex HSCL800 that is an automated immune assay system. @*Results and discussion@#This center was begun to conduct the vaccination of workers from 2011. Among total 63 individuals involved in this study 53 (84.1%) were vaccinated against hepatitis B and 10 (15.9%) were not vaccinated. From the vaccinated 53 workers, 47 (88,7%) have immunized (anti-H Bs > 1 Ou/ml) but 6 (11.3%) of them were not immunized (anti-HBs <1 Ou/ml).</br> Therefore 1(1,9%) worker of them received just first dose, 14 (26.4%) workers were injected second dose, whereas 38 (71.7%) workers were vaccinated with third dose. The study shows that 12 (85.7%) workers after second dose and 34 (89.5%) workers after third dose were immunized.@*Conclutions@#As a result of hepatitis B vaccination, 88.7% of workers of the NCTM have had immunized against HBV. The final evaluation shows that 36 (57%) of workers had stable, 17 (27%) increased, and 10(16%) decreased level of immunization than the previous year.

The fat transplantation of upper eyelid depression with autologous fat transplantation booster / 中华整形外科杂志

Objective@#To summarize the clinical effects of meticulous fat transplantation with fat grafts in the treatment of sunken upper eyelid.@*Methods@#From September 2016 to January 2019, 58 patients with sunken upper eyelid were treated in the 940th Hospital of the Joint Logistic Support Force of PLA. There were 2 males and 56 females, aged from 20 to 63 years. Among them, 14 cases were congenital, 30 cases were senile, 8 cases were postoperative, and 6 cases were traumatic. The prepared autologous granule fat was extracted with a 1 ml syringe, which matched with a 1.0 mm diameter needle. The 1 ml syringe was packed into the card slot of a fat graft booster, and the needle was inserted into the orbital fat zone of a depressed upper eyelid to homogenously inject the granule fat. For patients with iatrogenic and traumatic upper eyelid depression, the adhesion was released by small needle knife before injection. For those with aging skin, subcutaneous injection of nano-fat was applied.@*Results@#The amount of granule fat transplantation was 0.5 ml to 3.6 ml, with an average of 1.5 ml. The amount of nano-fat injection was 0.5 ml to 1.0 ml, with an average of 0.7 ml. All patients were followed up for 1 month to 2 years. Except 2 patients with severe traumatic upper eyelid depression, the other patients were satisfied with their full and natural upper eyelids after treatments.@*Conclusions@#When the upper eyelid depression was treated with granule fat transplantation by the booster, the small needle knife peeling technique and nano fat transplantation can be combined to correct different types of congenital, aging and surgical derived sunken upper eyelid and traumatic sunken upper eyelid from mild to severe cases. At the same time, the skin of the upper eyelid can be rejuvenated as well.

Prevalence and factors associated with seroprotection after primary series of hepatitis b vaccination among children seen in the outpatient setting of Philippine Children’s Medical Center

BACKGROUND@#Hepatitis B is a vaccine-preventable condition that could develop into cirrhosis and hepatocellular carcinoma. Identifying patients at risk for Hepatitis B infection despite the universal implementation of Hepatitis B vaccination will help improve the immunization program.@*OBJECTIVE@#To determine the prevalence and factors associated with seroprotection among children 3 months to 18 years old primary Hepatitis B vaccination series.@*METHODOLOGY@#This is a cross-sectional study among children 3 months to 18years old with complete Hepatitis B immunization. Demographic, social and clinical data were correlated with response to HBsAg, Anti-HBs and Total Anti-HBc tests.@*RESULTS@#Among 110 subjects from different age groups, 52% had seroprotective anti-HBs levels (>10 mIU/ml). Seventy four percent seroprotection was seen in subjects with <5 years interval from vaccination, 26% in cases after 5-10 years, and 38% at 10 years after vaccination with significant difference. Other factors such as gender, geographic area, type of vaccine, schedule, age at first dose and place of vaccine were not associated with seroprotection.@*CONCLUSION@#Fifty two percent seroprotection from Hepatitis B infection among different age groups was demonstrated in our study. Interval year after vaccination was the only factor established to have significant association with seroprotection, with < 50% decline of anti-HBs level at 5 years or more after vaccination. @*RECOMMENDATIONS@#Community studies with larger population are needed. Anti-HBs detection 5 years or more post-vaccination may be considered to identify patients at risk for breakthrough infection. Repeat serologic testing among non-seroprotected subjects is recommended.

Long-term Protection Against the Hepatitis B Virus Detected Through an Early Response to a Booster Dose Injection

To determine the duration of protection conferred by the hepatitis B (HB)vaccination and the necessity of a booster dose. Methods: Immediately after the initial bloodsampling, 252 youths (aged 18.8-20.5 years, 52% females) with a history of neonatal HBvaccination with one dose of the HB vaccine received a booster. Serum concentrations ofantibodies against the HB surface antigen were assessed in samples collected before and10-14 days after the booster. Seroconversion from concentrations <10 to ?10 IU/L weredefined as a positive immune response. Results: Of the 252 participants, 131 were sero-susceptible and 114 responded. Conclusions: Nearly 90% of young people preserved theirlong-term protection; the results of this study do not support the use of an HB boostervaccination

Reemergence of mumps in São Paulo, Brazil - the urgent need for booster shot campaign to prevent a serious infectious disease

Abstract INTRODUCTION: Neglected infectious diseases like mumps may be opportunistic in controlled areas with low vaccine coverage, particularly in developed and emerging countries. METHODS: A retrospective analysis of mumps-related data from 2001 to 2016 for São Paulo State, Brazil was conducted. RESULTS: From 2014 to 2015, there was an increase of 82% in reported mumps cases in São Paulo, with prevalence of n=49 and 297, respectively in young adults aged 15-29 years. CONCLUSIONS: A booster-shot campaign on MMR vaccination is recommended to prevent the spread of mumps in unvaccinated children and recipients of only the first dose.

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.

A Single Center Analysis of the Positivity of Hepatitis B Antibody after Neonatal Vaccination Program in Korea

The antibody to hepatitis B surface antigen (anti-HBs) seropositivity rate after 3 doses of hepatitis B virus (HBV) vaccination during infancy period is known to be higher than 90%. However, a considerable number of vaccines do not form protective anti-HBs or chronologic decrease of anti-HBs. We retrospectively collected data of HBV serologic test results in 20,738 individuals from 2000 to 2015. After exclusion criteria were applied, 19,072 individuals were included. We analyzed the anti-HBs seropositivity rate, anti-HBs disappearance rate, anti-HBs positive seroconversion rate after receiving a booster vaccine, and the difference in anti-HBs positivity between the 2 groups; group A (born before 2005, while both recombinant vaccines and plasma-derived vaccines were used) and group B (born after 2005, when only recombinant vaccines were used by national regulation). The anti-HBs seropositivity rate was 55.8%, but there was a significant difference in the rate of seropositivity for anti-HBs between the group A and B (53.0% vs. 78.1%, P < 0.001). There was no significant age-adjusted difference in the mean seropositivity rate between the 2 groups (P = 0.058). In addition, the anti-HBs positivity rate was significantly lower in the group A as compared with the group B during infancy (83.1% vs. 92.1%, P < 0.001). A total of 1,106 anti-HBs-positive subjects underwent serologic tests more than twice. Of these, 217 subjects (19.6%) showed anti-HBs disappearance. After booster vaccinations, 87.4% (83/95) achieved seroconversion from seronegative to seropositive. Our results highlight the importance of lifelong protection against HBV and the possible necessity of booster vaccination after adolescent period.

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 .

Awareness and adoption of child restraint seats in cars in an Indian city.

Background: Protective measures for children like restraints and booster seats are seldom used in developing countries. The thriving Indian economy has resulted in booming car sales, particularly in urban areas, unfortunately the number of car crashes and accidents on roads have also increased manifold. Objective of current study was to evaluate the awareness and usage of child safety measures in cars in an Indian city. Methods: 150 parents were given a self-report questionnaire and their views, practices and attitude towards child restraint seats and booster seats were assessed. Results: Only 22% of parents used child restraints and 11% used booster seats. Among the users, 73% (infant seats) and 84% (booster seats) admitted to inadequate knowledge about installation and utilization. Conclusion: Usage and knowledge about child safety measures in cars is abysmal. Measures to improve adoption of car safety devices will have substantial and tangible benefits.

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.