甲型肝炎减毒活疫苗与灭活疫苗免疫效果的比较

目的 观察甲型肝炎（甲肝）减毒活疫苗Ｈ２株与ＬＡ－１株的不同剂量、不同免疫程序的免疫原性及抗体动脉变化。方法 在河北、广西两地５选择３１８名经甲肝抗体检测为阴性的易感儿童,按不同剂量程序及不同甲肝疫苗,分为６组,并在首剂接种后１、６、７、１２、１３月份分别采集血清标本,检测甲肝总抗体。结果 各组抗体水平均于再免疫后１个月达高峰,以后开始下降,再免半年后抗体水平仍明显高于初免抗体水平;灭活于再免疫后     

Outbreak of measles in a highly vaccinated secondary school population.

OBJECTIVE: To examine the factors associated with measles vaccine effectiveness and the effect of two doses of vaccine on measles susceptibility during an outbreak. DESIGN: Retrospective cohort study. SETTING: A secondary school in the City of Toronto. SUBJECTS: The entire school population (1135 students 14 to 21 years of age). MAIN OUTCOME MEASURES: Risk of measles during an outbreak associated with age at first measles vaccination, length of time since vaccination, vaccination before 1980 and whether date of vaccination was estimated; vaccine efficacy of one dose versus two doses. RESULTS: Eighty-seven laboratory-confirmed or clinically confirmed cases of measles were identified (for an attack rate of 7.7%). The measles vaccination rate was 94.2%, and 10% of the students had received two doses of measles vaccine before the outbreak. Among those who had received only one dose of vaccine, vaccination at less than 15 months of age was associated with vaccine failure (relative risk 3.62, 95% confidence interval 2.32 to 5.66). There was no increased risk of vaccine failure associated with length of time since vaccination once the relative risk was adjusted for age at vaccination in a stratified analysis. Vaccination before 1980 and an estimated date of vaccination were not associated with increased risk of vaccine failure. Administration of a second dose of vaccine during the outbreak was not protective. Two doses of vaccine given before the outbreak conferred significant protection, and the relative risk of failure after one dose versus two doses was 5.0 (95% confidence interval 1.25 to 20.15). Of the 87 cases, 76 (87%) could have been prevented had all the students received two doses of measles vaccine before the outbreak, with the first at 12 months of age or later. CONCLUSIONS: Delayed primary measles vaccination (at 15 months of age or later) significantly reduced measles risk at later ages. However, revising the timing of the current 12-month dose would leave children vulnerable during a period in which there is increased risk of complications. The findings support a population-based two-dose measles vaccination strategy for optimal measles control and eventual disease elimination.     

Prevalence of antibodies to poliovirus in 1978 among subjects aged 0-88 years

The antibody state of a population aged 6 months to 88 years to poliovirus types 1, 2, and 3 was determined by examining 919 sera collected in Lancashire, London, and southern and south-east England. In subjects aged over 2 years the immune state was surprisingly uniform, although the older patients had probably acquired practically all their antibodies as a result of natural infection and those under 16 through vaccination. at least 95% had detectable antibodies to at least one poliovirus type and about 60% to all three types, with the exception of a cohort of children born between 1963 and 1968, in whom the proportions were about 80% and 40% respectively. These children were born around the time of the changeover from inactivated to oral vaccine, when immunisation rates were low and there was confusion over the number of doses required. These results indicate that a complete course of vaccine or a booster dose at or around school-leaving age is necessary.     

Vaccination against hepatitis B infection in patients with end stage renal disease

Background: Experience of hepatitis B vaccination in a contemporary renal replacement programme is reported. Methods: A total of 406 patients were involved: 214 on haemodialysis, 97 on continuous ambulatory peritoneal dialysis, 67 predialysis (serum creatinine >400 µmol/l), and 28 with a failing transplant. Primary vaccination comprised recombinant hepatitis B vaccine (Engerix B) 40 µg intramuscularly at 0, 1, 2, and 3 months. Booster doses were administered three monthly if anti-HBs titre was <100 IU/l. Results: Uptake of vaccine was 61% (haemodialysis 70%, continuous ambulatory peritoneal dialysis 62%, predialysis 31%, transplant 61%, p<0.0001). Primary seroconversion occurred in 64% of vaccinated patients (anti-HBs; 10–100 U/l, 33%; >100 U/l, 31%). Booster doses led to further improvement in immunity in 66/115 (57%) patients after a first and 8/20 (40%) patients after a second booster dose, but uptake was again poor (first booster 74%, second 31%). Seroprotection declined unexpectedly rapidly; after a mean of 16 months 71/115 patients (62 %) had a significant fall in their anti-HBs titres; 30/115 (26%) lost detectable antibody. Conclusions: Routine hepatitis B vaccination of patients with end stage renal failure is logistically difficult to administer on a large scale; primary seroconversion is relatively poor, but improves after repeated booster doses; protective anti-HBs titres decline rapidly, and yearly antibody checks with selective booster doses will be required to maintain seroprotection. The cost effectiveness of a vaccination programme will vary greatly depending on the prevalence of hepatitis B in the population at risk.     

Local reactions after the fourth dose of acellular pertussis vaccine in South Australia

OBJECTIVE: To assess the reported rate of local reactions after administration of acellular pertussis vaccine (DTPa) according to dose number and type of pertussis vaccine (whole-cell or acellular) used for the primary course, and to document the severity and outcome of fourth-dose local reactions. DESIGN AND SETTING: Retrospective review. Reports of adverse events after vaccination in South Australia between 1 January 1997 and 31 December 2000 were reviewed, and a questionnaire administered to all parents who reported a local reaction after the fourth dose of DTPa. MAIN OUTCOME MEASURES: The number, and rate per 100 000 administered doses, of local reactions following the primary and booster doses of DTPa, and of local reactions after the fourth-dose in cohorts of children whose primary vaccinations were with either DTPw or DTPa. Redness and/or swelling at the injection site as reported by parents. RESULTS: Of 581 reported adverse events after vaccination, 138 were local reactions after a pertussis-containing vaccine. Primary vaccinations with DTPa was a significant risk factor for a fourth-dose local reaction (relative risk, 6.7; 95% CI, 2.4-18.5). Parental questionnaires were completed for 45 of the 71 children (63%) with reported local reactions after the fourth dose of DTPa; extensive limb swelling was reported in 8 children (18%) and all except one child had recovered by the time of review. CONCLUSIONS: Parents should be informed that children receiving booster doses of DTPa vaccine, after primary doses with DTPa, are at increased risk of local reactions (which tend to resolve spontaneously) but not of systemic effects. Studies should be initiated to investigate the pathogenesis and the risk of recurrence of local reactions to further improve vaccination schedules.     

儿童集体单位水痘暴发与水痘疫苗接种效果的病例对照研究

目的评价目前水痘疫苗接种方案对儿童集体单位水痘暴发的保护效果。方法在发生水痘疫情的儿童集体单位,按年龄分层,以接种疫苗为暴露因素进行1∶1配对病例对照研究,评价疫苗保护效果。结果儿童于1～2岁接种水痘疫苗后,在2～8岁时发生水痘的OR值为0.083(95%CI 0.037～0.185),疫苗保护效果为91.7%(95%CI 81.5%～96.3%);在9～15岁时OR值差异无统计学意义。结论 1～2岁接种水痘疫苗后6年内有良好的保护作用,但之后会快速衰减,应适时接种第2剂疫苗。     

Association between administration of hepatitis B vaccine at birth and completion of the hepatitis B and 4:3:1:3 vaccine series

CONTEXT: The association between infant age at initiation of hepatitis B vaccination and completion of the 3-dose hepatitis B vaccination series is unclear. OBJECTIVE: To assess the association between administration of the first dose of hepatitis B vaccine within 7 days of birth and completion of the hepatitis B vaccine series and the 4:3:1:3 vaccine series (4 doses of diphtheria-tetanus-pertussis vaccine, 3 doses of polio vaccine, 1 dose of measles-containing vaccine, and 3 doses of Haemophilus influenzae type b vaccine). DESIGN, SETTING, AND PARTICIPANTS: Analysis of data from the 1998 National Immunization Survey, a random-digit-dialing telephone survey (n = 34,480 completed interviews) of parents of children aged 19 to 35 months from 50 states and 28 selected urban areas in the United States that included a provider record check mail survey. MAIN OUTCOME MEASURES: Percentage of infants who received at least 3 doses of hepatitis B vaccine and percentage who received the 4:3:1:3 vaccine series, by age at receipt of the first dose of hepatitis B vaccine. RESULTS: Overall, 86.9% of children 19 to 35 months of age in 1998 received 3 or more doses of hepatitis B vaccine, and 79.9% completed the 4:3:1:3 vaccine series. Multivariate analysis indicated that, compared with children who received the first hepatitis B vaccine dose within 7 days of birth, odds ratios (ORs) for not completing the 3-dose hepatitis B vaccine series among children who received the first dose at 8 to 41 days, 42 to 91 days, 92 to 182 days, 183 to 273 days, and 274 or more days of age were 2.4 (95% confidence interval [CI], 2.0-3.0), 7.8 (95% CI, 6.5-9.3), 9.6 (95% CI, 7.0-13. 3), 18.3 (95% CI, 12.0-28.0), and 46.6 (95% CI, 33.7-64.5), respectively; ORs for not completing the 4:3:1:3 vaccine series among these same groups were 1.0 (95% CI, 0.8-1.1), 1.0 (95% CI, 0. 8-1.1), 1.7 (95% CI, 1.3-2.3), 3.8 (95% CI, 2.6-5.6), and 4.0 (95% CI, 2.9-5.5), respectively. CONCLUSION: Administration of the first dose of hepatitis B vaccine at birth is associated with increased likelihood of completion of the hepatitis B vaccination series. JAMA. 2000;284:978-983     

Seroconversion after hepatitis B vaccination in healthy young adults,and the effect of a booster dose

OBJECTIVE: Previous studies have shown that 5% to 15% of healthy people do not show a protective antibody response following hepatitis B vaccination. The study was done to determine the protective efficacy of vaccination in healthy young adults 1 to 4 years after the three dose vaccination series and to study the effect of a booster dose on non-responders and hypo-responders. DESIGN: Prospective intervention study. SETTING: From January to June 2000, Faculty of Medicine, University of Colombo. STUDY GROUP: 258 volunteers from five batches of medical students vaccinated with three doses of the recombinant vaccine at 0, 1 and 6 months. RESULTS: 9.5% were non-responders. Duration of vaccination, sex and body mass index were not significantly associated with anti-HBs levels. 28.6% had potential risk factors for acquiring HBV infection. 86.3% of non-responders developed protective anti-HBs titres after a booster dose. The persistent non-responders did not have a chronic illness or past HBV infection. CONCLUSIONS: A substantial number do not seroconvert after hepatitis B vaccination. Testing of blood for anti-HBs one month after vaccination is recommended to recognise non-responders as a booster dose will be beneficial in the majority of them.     

Antibody to Hepatitis B Surface Antigen in Vaccinated Health Care Workers

Background

Health care workers (HCWs) in Armed Forces are immunised against Hepatitis B virus (HBV), however they are not subjected to anti-HBs (antibody to Hepatitis B surface antigen) assessment after primary vaccination. The present study was undertaken to determine the protection offered by HBV vaccine in HCW.

Methods

Cross-sectional study was carried out at tertiary care hospital. A total 146 HBV vaccine compliant HCW were evaluated for quantitative anti-HBs by enzyme immune assay.

Result

129 (88.4%) subjects had protective levels of anti-HBs. Higher age at vaccination was an important risk factor in low vaccine response. Decline in anti-HBs with time was evident. Anti-HBs levels were more than 10mIU/ml in subjects even after 11 years of primary vaccination. There was no difference in protection in booster and non booster groups.

Conclusion

Age is the most important factor in HBV vaccine response. Booster dose of HBV vaccine is not necessary in healthy HCW for atleast ten years after primary vaccination. The study recommends early primary vaccination of HCW and ‘initial’ anti-HBs assay for confirmation of vaccine response.Key Words: Anti-Hepatitis B surface antigen, Health care workers, Hepatitis B virus vaccine     

Vaccination against hepatitis A in children aged 12 to 24 months [corrected

BACKGROUND: Current hepatitis A vaccines are either licensed for children >2 years of age, as in the U.S. or Chile, or >1 year of age, as in Europe and other parts of the world. Recent recommendations for immunization against hepatitis A have included routine vaccination of children in areas or regions of higher endemicity. However, data on hepatitis A vaccination in toddlers aged between 1 and 2 years are scarce. METHODS: This open clinical study investigated the reactogenicity and immunogenicity of two doses (0, 6-month schedule) of an inactivated hepatitis A vaccine (Havrix pediatric, Glaxco SmithKline Biologicals, Rixensart, Belgium) in 120 seronegative children aged 12-24 months. RESULTS: Pain at the injection site and irritability were the most frequently reported local and general symptoms, respectively. No serious adverse events related to the study vaccine were reported. One month after the first dose, all but one subject had antibodies against hepatitis A with a GMT of 159 mIU/mL. After the booster dose, all had antibodies with a GMT of 2,939 mIU/mL. CONCLUSIONS: Our data show that the inactivated hepatitis A vaccine was well tolerated by these toddlers and that the vaccine elicits a good immune response.     

Invasive Haemophilus influenzae type b disease in Sydney children 1985-1987: a population-based study

OBJECTIVE: To determine the incidence and age distribution of invasive Haemophilus influenzae type b (Hib) disease in children (0-14 years) in the Sydney Statistical Division (SSD). DESIGN: Retrospective ascertainment from a defined population, 1985-1987. Eligible cases had Hib isolated from a normally sterile site or endoscopically proven epiglottitis. SETTING: Sydney Statistical Division, which had a population of children aged 0-4 years of 229 165 in 1986. PATIENTS: Cases were identified from all potential sources of relevant recorded information. MAIN OUTCOMES: There were 292 eligible cases. Among 284 previously well children, those under 18 months of age contributed 81 of 143 cases (57%) of meningitis and 22 of 71 (71%) of cellulitis/arthritis but only 8 of 91 (11%) of epiglottitis and 4 of 18 (22%) of infection in other foci. Overall, 9% of cases had occurred by 6 months of age, 42% by 18 months and 55% by 24 months. The annual incidence of invasive Hib disease was 38.5 per 100,000 children aged 0-4 years. In areas with the lowest proportion of young children (less than 5.5%), the incidence of Hib disease in the first 12 months of life was significantly lower than in the remainder of Sydney, although there were no differences in overall disease incidence in the age group 0-4 years. CONCLUSIONS: This study indicates that approximately 1 in 500 urban Australian children develop invasive Hib disease by their fifth birthday. Vaccination of children in Sydney with a conjugate Hib vaccine at 18 months of age would result in a greater potential reduction in Hib disease than in the United States, where universal vaccination at this age is current policy.     

Optimal age for measles and mumps vaccination in Australia

Trivalent measles-mumps-rubella vaccine has recently replaced measles-mumps vaccine in Australia and is recommended as a single dose at the age of 12 to 15 months, with the exception of Aboriginal children in central Australia who are vaccinated at 9 months. The timing of measles vaccination has been controversial not only in Australia but also in the United States, where measles outbreaks continue to occur. This study aimed to determine seroconversion rates for measles-mumps vaccine in children aged 12 to 18 months and to make a recommendation for the timing of vaccination based on seroconversion rates and attack rates. The parents of 425 children aged 12 to 18 months gave consent for their children to have serum collected at the time of measles-mumps vaccination and three months later. The mean age at vaccination of the children who had two serum samples for measles and mumps antibody estimations was 13.9 months (mode, 13.1). The seroconversion rate for measles was 95% (314/329) (95% confidence interval (CI), 92.5% to 97.3%) and for mumps 97% (309/320) (95% CI, 93.8% to 98.1%). There were no statistically significant differences in the rates of seroconversion for measles or mumps related to age in months at the time of vaccination or in post-vaccination measles antibody titres related to age at vaccination. Post-vaccination mumps antibody titres tended to be lower in older vaccinees. None of the children who presented for vaccination had serological evidence of prior measles infection but five had evidence suggestive of prior mumps. As the seroconversion rates for measles and mumps vaccines were very high in these children it was concluded that no advantage resulted from delaying vaccination until 15 months and that the current National Health and Medical Research Council recommendations for vaccination at age 12 to 15 months should remain.     

国产乙型肝炎血源疫苗免疫保护持久性及加强免疫△

目的确定国产乙肝血源疫苗低剂量免疫保护持久性及何时需要加强免疫。方法采用放射免疫（ＲＩＡ）法测定新生儿计划免疫７年后的血清学效果和加免实验的抗体反应。结果１０１８名乙肝免疫儿童的保护性抗体阳性率从免后１～２年的７５．０％下降为第７年的４８．２％,而ＨＢｓＡｇ和抗－ＨＢｃ阳性率却均始终处于低水平。１４４名免后６～７年且ＨＢｓＡｇ和抗－ＨＢｃ均阴性儿童,加免前抗－ＨＢｓＧＭＴ为１０．４ｍＩＵ／ｍｌ,抗－ＨＢｓ阳性率５４．９％;加免后１个月和１年,抗－ＨＢｓＧＭＴ分别为１９０．６和２５．３ｍＩＵ／ｍｌ,而抗－ＨＢｓ阳性率则分别为８９．６％和７５．５％。加免后１个月抗－ＨＢｓＧＭＴ和阳性率均显著高于加免前的水平（Ｐ＜０．０１）。但加免后１年时抗－ＨＢｓＧＭＴ又接近加免前水平,而阳性率仍显著高于加免前。６５名加免前抗－ＨＢｓ阴性儿童,加免后１个月有４０名儿童抗－ＨＢｓ≥１００ｍＩＵ／ｍｌ,提示乙肝疫苗免后抗体阴转者可能仍保持免疫记忆。结论国产乙肝血源疫苗低剂量免疫有很好的免疫保护持久性,初免后７年不必加强免疫。     

采用间接免疫荧光法监测流行性出血热疫苗接种3年后的人群抗体水平

目的：研究接种疫苗３年后人群抗体水平及间接免疫荧光抗体检测方法在流行性出血热免疫抗体检测中的应用。方法：采用间接免疫荧光法测定特异性ＩｇＧ抗体,并对２６６例血清样本进行分析。结果：全程接种与未加得抗体阳性率分别为７０．６３％,５９．７９％,并拍摄到抗原抗体免疫荧光结合物。结论：全程接种疫苗３年后人群抗体保持较高水平,加强接种后免疫效果更佳。     

Oral polio vaccine. Effect of booster vaccination one to 14 years after primary series.

We studied the persistence of antibody after vaccination and the response to booster revaccination with trivalent oral polio vaccine (TOPV) administered at varied intervals after the primary series in a large group of children. Decline in antibody was related to intervals since last vaccination, and not to sex, age, age at primary vaccination, or type and number of previous administrations. Geometric mean titers of neutralizing antibody were 11.3 for type 1 and 8.0 for types 2 and 3 poliovirus when vaccine had been given within the previous year, declining to 3.2, 3.0, and 2.1 for types 1, 2, and 3 after nine years. Most children with an initial titer of 4 or less responded to revaccination with a fourfold or greater increase in titer of IgG. Geometric mean titers for all three types of polio dropped to this level when last TOPV administration had been five to six years or more.     

Persistent efficacy of live attenuated hepatitis A vaccine (H2-strain) after a mass vaccination program

Background Live attenuated hepatitis A vaccine （ H2 strain） is widely applied in prevention of hepatitis A epidemic in China and other countries now. It is essential to observe and confirm the vaccine immune efficacy, population antibody level and its persistent efficacy after mass immunization. Methods A total of 220 children with negative anti-HAV antibody （ aged 1-3 years） were taken for follow-up assay to observe seroconversion and geometric mean titre（GMT） level 2 months, 12 months, 6 years, and 10 years after inoculation. Another survey sampled from subjects of different age groups （3, 6, 9, 15, 18, 25 and 35 years） to compare anti-HA antibody positive rate before and after inoculation performed 10 years previously. Epidemiological observations were taken for 10 years to evaluate the relationship between vaccine coverage and hepatitis A morbidity. Serum antibody to HAV was detected by enzyme linked immunoassay （ELISA, calibrated by WHO international reference） and ABBOTY Axsym HAVAB microparticle enzyme immunoassay. Results Seroconversion in follow-up assay 2 months and 10 years after inoculation was 98.6% and 80. 2% respectively. For children, the vaccination anti-HA antibody positive rates were significantly different before and after 10 years, 7.69% cf 70.45% （aged 3 years） and 52. 58% cf 71.78% （aged 18 years）. When vaccine coverage rose from 57% to 74%, there were no any HA epidemics. When vaccine coverage reached 85%, there were no any HA cases. With vaccine coverage between 85% and 91%, there were no any HA cases in cohorts from the age of 1 year to 15 years during the 10 years. Conclusions Live attenuated hepatitis A vaccine has an obvious long-term effectiveness in prevention and control of HA epidemics through mass vaccination.     

Intradermal inoculation with Heptavax-B. Immune response and histologic evaluation of injection sites

The high cost of hepatitis B vaccine has limited its widespread use. Low-dose, intradermal injections of vaccine represent one option for reducing the cost. In this study, 92 nonimmune medical students were given three 0.1-mL intradermal injections of Heptavax-B containing 2 micrograms of hepatitis B surface antigen (HBsAg) at 0, 1, and 6 months. By 6 months, 90% of the subjects had developed protective levels of antibody to HBsAg (greater than or equal to 10 mIU/mL). Follow-up at 1 year showed a geometric mean concentration of antibodies to HBsAg of 396 mIU/mL for the group, and 95% had levels of antibody to HBsAg greater than or equal to 10 mIU/mL. A level of antibody to HBsAg of greater than 100 mIU/mL also was observed in more than 75% of subjects. Side effects included induration of the inoculation site in 18% at 6 months, which disappeared by 12 months, and macules that persisted at 1 year in 63%. The administration of hepatitis B vaccine intradermally is an attractive, low-cost alternative in the United States, where universal vaccination of preschool children or adolescents is being contemplated, and where booster doses are being considered.     

Live varicella vaccine in both immunocompromised and healthy children

BACKGROUND: There is no information on the use of live varicella vaccine in Mexican children. Our objective was to evaluate antibody response and safety of the live varicella vaccine in both healthy and immunocompromised Mexican children. METHODS: One hundred children with no history of varicella/zoster were vaccinated with a live attenuated varicella vaccine. According to their immune status, patients were divided into either a compromised (leukemia, solid tumors, chronic renal failure, and cirrhosis) or a healthy children group. Serum IgG antibodies against VZV were measured by ELISA at baseline and at 3 and 6 months after vaccination. RESULTS: A positive VZV-ELISA at baseline was detected in 36 of 67 (53.7%) immunocompromised children and in 22 of 33 (66%) healthy children. Among VZV-seronegative children, seroconversion at 6 months post-vaccination was observed in 90.3% of compromised children and in 100% of healthy children. Increases in serum antibody levels at 3 and 6 months post-vaccination was similar in both groups. VZV vaccine-related adverse reactions, mostly mild and local, were detected in 29% of the children. Three compromised children had a mild rash symptomatic of varicella after vaccination. CONCLUSIONS: About 50% of immunosuppressed children (mean age 8.8 +/- 3.6 years) with no varicella history were VZV-seronegative. Almost all of these compromised VZV-seronegative patients seroconverted 6 months after vaccine. In addition, antibody titers were similar in both compromised and healthy children.     

成都市91名医务人员接种新冠疫苗加强针后特异性抗体分析

目的 了解成都市公共卫生临床医疗中心医务人员接种新冠疫苗加强针后1月血清特异性抗体产生情况,并与新型冠状病毒肺炎（简称新冠肺炎）既往感染者疫苗免疫后特异性抗体比较,分析加强免疫针效果。方法 以接种新冠灭活疫苗第三剂（加强免疫针）的医院医务人员为试验组,以接种两剂新冠灭活疫苗的新冠肺炎既往感染者为对照组。使用化学发光法分别检测对试验组加强免疫后1月、对照组免疫后24~78 d（中位时间58 d）血清SARS-CoV-2 IgG抗体及总抗体,比较对照组疫苗免疫前后抗体变化以及两组免疫后抗体的差异。结果 试验组加强免疫后SARS-CoV-2 IgG阳性率为94.5%（86/91）,均值（6.92±3.40）COI、总抗体均值（460.64±265.98）COI。男、女性IgG阳性率、IgG量、总抗体量的差异均无统计学意义（P>0.05）,≥40岁组IgG阳性率及总抗体量均低于22~<30岁组（F=3.269,P<0.05）;采用Fisher确切概率法分析,对照组疫苗免疫后SARS-CoV-2 IgG抗体及总抗体显著高于免疫前（P<0.001）。试验组加强免疫后1月和对照组疫苗免疫后SARS-CoV-2总抗体分别为（460.64±265.98） 和（595.40±294.36）COI,试验组加强免疫后1月比对照组疫苗免疫后低,差异有统计学意义（P<0.05）。结论 接种新冠灭活疫苗加强免疫针后体内抗体将快速达到高峰,虽然效果可能会受到年龄的影响,但仍普遍有效。新冠肺炎既往感染者免疫接种后的保护力可能强于非感染者加强免疫接种后。符合加强免疫接种条件的非感染者以及免疫接种条件的新冠肺炎康复者,都该及时接种以减少感染或再次感染SARS-CoV-2的风险。     

Immunoglobulin deficiency and idiotype expression in children developing Haemophilus influenzae type b disease after vaccination with conjugate vaccine. The Collaborative Study Group

OBJECTIVE.--Haemophilus influenzae type b (Hib) conjugate vaccines are effective in preventing Haemophilus disease in most children. The reasons why the vaccination fails in some children are unknown. This study investigated host factors in children who developed the disease despite conjugate vaccination. DESIGN, PATIENTS, OUTCOME MEASURES.--A convenience sample of 23 patients in whom Hib disease developed 14 days or more after conjugate vaccination was investigated for the presence of subnormal serum immunoglobulin concentrations and anticapsular antibody responses to Hib disease. We also investigated expression of the Hib idiotype 1 (Hibld-1), a serological marker of a VKII chain that comprises a major portion of the normal variable region repertoire of the antibody response to Hib polysaccharide. The results were compared with those of 149 patients in whom the unconjugated Hib polysaccharide vaccine failed and of 90 unvaccinated patients who developed the disease. RESULTS.--Compared with children in whom the unconjugated polysaccharide vaccination failed, the relative risk of a subnormal serum concentration of IgM, IgA, IgG, and/or IgG2 in the children in whom the conjugate vaccination failed was 4.9 (95% confidence interval [CI], 1.8 to 14; P less than .003) and of IgG2 was 22 (95% CI, 3.5 to 146; P less than .001). With the exception of the children with subnormal serum immunoglobulin concentrations, most of the children with conjugate vaccination failure showed normal or high anticapsular antibody responses to the disease, whereas the children with polysaccharide vaccination failure showed impaired responses. The Hibld-1 was expressed by the majority of the children in both vaccination failure groups and of the unvaccinated patients. CONCLUSIONS.--In most patients, vaccination failure is not attributable to lack of expression of the variable region gene encoding Hibld-1. However, children in whom conjugate vaccination has failed frequently have subnormal serum immunoglobulin concentrations and should be evaluated for immunodeficiency.