无锡市甲型H1N1流感及季节性流感疫苗接种效果分析

目的调查流感样病例(ILI)和无锡市一般人群中甲型H1N1流感疫苗及季节性流感疫苗的接种情况,评估疫苗接种后对人群的保护效果。方法以无锡市2家哨点医院为基础,采集流感样病例病毒核酸检测阳性的病例作为病例组,共1 529人,同时按照"病例"的电话信息,随机产生电话号码选择、年龄匹配的一般人群作为对照组,共380人。结果病例组甲型H1N1流感疫苗接种率为6.1%(94/1 529),对照组甲型H1N1流感疫苗接种率为12.1%(46/380),两组比较,差异有统计学意义(P0.01);甲型H1N1流感病例中接种甲型H1N1流感疫苗的比例为12.5%(3/24),门诊检测阴性的ILI病例接种甲型H1N1流感疫苗的比例为6.1%(78/1 273),"接种甲型H1N1流感疫苗"因素的OR值为0.457(P=0.201);以电话调查一般人群(330例)作为对照组,接种甲型H1N1流感疫苗的比例为13.3%(44/330),OR值为1.077(P=0.908)。结论该次调查说明接种甲型H1N1流感疫苗对预防流感样病例有一定效果,但由于样本量较少,24种方法病例对照分析均未得出差异有统计学意义。     

长沙市居民甲型H1N1流感知识态度行为调查

目的 了解湖南省长沙市城乡居民关于甲型H1N1流感的知识、态度、行为现状,为开展社区健康教育提供依据.方法 运用多阶段随机抽样的方法,对长沙市城乡地区14-65岁常住居民1 294人进行人户调查,调查内容包括个人基本资料、预防甲型H1N1流感相关知识态度行为、疫苗接种及对媒体需求等情况.结果 1 294人中,不知道甲型H1N1流感流行者占14.1%;对甲型H1N1流感相关知识的知晓率为18.2%～88.6%,其中对感染甲流不一定会发热的知晓率最低(18.2%);农村居民的知晓率普遍低于城市和城镇居民;大流行期间外出戴口罩的比例为36.1%,就医戴口罩为39.3%;出现发热及呼吸道症状后选择自己买药治疗者占47.8%;在公共场所打喷嚏时用纸巾遮掩者为24.0%,在家打喷嚏时用纸巾遮掩者为24.7%;既往从未接种过普通流感疫苗者占80.3%;甲型H1N1流感疫苗接种率为10.4%,未接种者中不愿意接种甲型H1N1流感疫苗占37.1%.结论 长沙市特别是农村地区居民对甲型H1N1流感及流感疫苗相关知识了解不足且不全面,个人防护意识差,进一步开展健康教育工作有利于加强流感防控.     

社区医护人员甲型H1N1流感院内感染防控知信行调查

目的了解社区医疗机构医护人员防控甲型H1N1流感院内感染的知信行现状及影响因素。方法通过多阶段抽样方法确定调查对象,采用集中自填统一调查问卷,调查其防控甲型H1N1流感医院感染知识态度和行为,运用F值或t值及χt2rend进行检验,采用二项分类logistic回归分析影响接种流感疫苗的因素。结果共调查247名医护人员,不同工作年限的医护人员知识得分差异有统计学意义(P0.01),随着知识得分下降,所占人数增加,且差异有统计学意义(P0.05);25.1%的医护人员认为自己有可能在医院感染甲型H1N1流感;43.32%医护人员懂得对佩戴医用防护口罩进行密合性检查;21.05%医护人员接种过季节性流感疫苗;Logistic回归分析表明,单位负责接种季节性流感疫苗费用是提高疫苗接种率的有力促进因素(OR=4.56,P0.01)。结论社区医疗机构防控甲型H1N1流感医院感染,宜加强相关知识培训,完善软硬件建设和资金投入,提高流感疫苗接种率。     

北京市4所高校新生甲型H1N1流感知信行调查

目的 了解大学生H1N1流感相关的知识、态度和行为状况,为制定防控策略提供依据.方法 采用自行设计的"北京市高校新生甲型H1N1流感知信行调查问卷",选择4所北京市高校进行调查.结果 共回收有效问卷787份,甲型H1N1流感知识21分,被调查学生得分平均为(8.9±1.8)分;不同性别、不同生源的学生的知识得分差异无统计学意义(P>0.05);各专业之间的差异有统计学意义(P<0.01);82.7 %(651/787)的学生认为在甲型H1N1流感流行期间,"我应该多了解相关知识,提高防范意识,加强防护措施",如果出现了甲型H1N1流感相关症状,87.0 %(685/787)的学生选择"立即去医疗机构诊断排查",90.1 %(709/787)的学生会劝说出现了甲型H1N1流感相关症状的舍友去医院就诊,71.4 %(562/787)的学生愿意接受甲型H1N1流感疫苗接种.不同学校、不同性别的学生之间对待H1N1流感疫苗接种态度的差异有统计学意义(P<0.05);不同专业之间的学生对待H1N1流感疫苗接种的态度比较,差异无统计学意义(P>0.05);大学生最希望获得甲型H1N1流感知识的信息渠道依次为电视台、手机短信、报纸、讲座和纸质宣传材料.结论 接受调查的学生正确预防H1N1流感的比例普遍较高,但尚存在部分知识掌握不确切、对流感疫苗接受度差等问题,有必要针对该人群的特点开展有针对性的健康教育工作.     

医护人员预防控制甲型H1N1流感医院感染的认知调查

目的 了解广州市医疗机构医护人员预防控制甲型H1N1流感医院感染的认知现状及影响因素.方法 采用容量比例抽样方法确定调查对象,采用集中自填统一调查问卷,运用F或t检验,比较不同人群预防控制知识得分;描述性分析采用构成比或百分率指标.结果 共成功收回27所医疗机构问卷1518份,医护人员预防控制甲型H1N1流感医院感染平均得分10.91分(满分17分),医疗机构级别、年龄组、性别、职称、工作部门、工作年限等不同人群得分差异有统计学意义(P＜0.05);在预防控制甲型H1N1流感医院感染知识的调查中,仅5.8％医护人员能正确回答转运甲型H1N1流感患者时医护人员的防护方法,仅22.1％能正确回答甲型H1N1流感诊疗场所空气消毒的常规措施;在对医疗机构应加强的工作调查中,93.2％的医护人员认为应该做好预检分诊工作,76.5％认为应加强医护人员预防控制甲型H1N1流感医院感染知识培训,75.8％认为应储备更多的防护装备.结论 大流行下医疗机构应增大对人力、物力和财力的投入,加强医护人员预防控制甲型H1N1流感医院感染知识、技能的宣传、培训力度,提高医护人员流感疫苗接种率.     

2009年华容县健康人群甲型H1N1流感疫苗免疫效果分析

目的了解健康人群接种甲型H1N1流感疫苗后的免疫效果及抗体水平。方法观察接种甲型H1N1流感疫苗人群中不良反应的发生情况;按照不同的年龄组随机抽取350人,采用描叙性流行病学方法,对疫苗的安全性和有效性进行评价;微量血凝抑制试验检测接种者甲型H1N1流感病毒抗体,SPSS16.0统计学软件对接种30 d后甲型H1N1流感与普通流感的发病率、就诊率及HI抗体阳转率进行比较。结果接种组接种甲型H1N1流感疫苗30 d后甲型H1N1流感与普通流感的发病率与就诊率均低于对照组,差异有统计学意义（P〈0.05）;接种甲型H1N1流感疫苗人群中共出现不良反应1 891例,总不良反应率为4.35%;接种组总体HI抗体阳转率显著高于对照组（χ2=4.27,P〈0.05）,达到欧盟药品评价委员会的标准,各年龄组间HI抗体阳转率差异无统计学意义。结论国产甲型H1N1流感疫苗具有较高的安全性与较好的免疫原性,适合在健康人群中普遍接种。     

东莞市中小学生、工人和居民甲型H1N1流感防治知信行现况调查

目的了解东莞市中小学生、工人和居民甲型H1N1流感防治知识、态度及行为现况,为下一步防控工作提供科学依据。方法选择东莞市小学、初中、工厂各1间,居民社区1个,其中小学和初中每个年级选择两个班进行整群抽样,社区和工厂采取随机抽样方法选取对象,采用自填式问卷调查甲型H1N1流感防治知识的认知水平、日常行为习惯及对待甲型H1N1流感的态度等。结果调查对象对甲型H1N1流感总体知晓率为69.63%,其中中小学生为75.32%,工人为64.10%,居民为52.46%,三者知晓率之间差异有统计学意义(χ2=45.98,P0.05);中小学生不带病上课、打喷嚏或咳嗽时捂嘴、每天洗手次数、洗手时点和洗手方式等卫生习惯方面均优于工人及居民,差异有统计学意义;有27.24%的调查对象认为甲型H1N1流感可怕,认为可怕的原因主要是甲型H1N1流感难以预防(52.68%)、该病易病死(46.34%)和没有特效药(41.22%);在未接种过甲型H1N1流感疫苗的调查对象中,仅58.10%表示愿意接种免费的甲型H1N1流感疫苗,不愿意接种的原因主要是担心疫苗的安全性。结论东莞市中小学生在甲型H1N1流感防治知识、态度及行为等方面均优于工人及居民,应在特定人群中有针对性地开展甲型H1N1流感可防可治、疫苗安全有效、不带病工作及正确洗手方法等关键知识点的宣传教育。     

攀枝花市甲型H_1N_1流感相关健康知识、态度和需求分析

目的了解人群对甲型H1N1流感的相关知识、态度、健康需求情况及防控技能的影响因素。方法采用整群分层抽样调查,对5个区县的学校、社区、村社及行政事业单位开展问卷调查。结果回收有效问卷934份,各职业人群、年龄段、文化程度的知识知晓率均有统计学差异(P0.05),而各地在知识知晓率方面未显示出统计学差异(P0.05)。知晓公众咨询电话号码的仅占180人(19.27%);Ordinal回归分析防控甲型H1N1流感技能掌握的影响因素,检验结果说明职业人群、性别、甲型H1N1流感相关知识点的知晓情况对公众掌握防控技能的影响具有统计学意义;对甲型H1N1流感感到恐慌的仅占调查人群的4.8%,到医院诊治是调查对象对自己或家人采取的显著倾向态度(P0.01)。大众对甲型H1N1流感相关知识和技能、甲型H1N1流感疫苗有较高的需求愿望,电视媒体依然是公众接受教育的主要手段和方式。结论对村民、甲型H1N1流感的一些错误认知、公众热线咨询电话号码需加强宣传。公众对防控甲型H1N1流感相关知识和技能、甲型H1N1流感疫苗有较高的需求愿望。     

麻杏石甘汤治疗轻症甲型H1N1流感的随机对照研究

[目的]评价麻杏石甘汤治疗轻症甲型H1N1流感的疗效及安全性。[方法]采用前瞻性随机对照研究。将纳入的114例随机分入对照组1、对照组2、中药组和联合组。观察4组疗效、不良反应、并发症的差异。[结果]114例病人完全痊愈;基线各指标相似,联合组入组后发热持续时间(h)短于对照组1及中药组,有统计学差异(P﹤0.05);4组其余疗效指标无统计学差异(P﹥0.05);不良反应及并发症发生率4组间无统计学差异(P﹥0.05)。[结论]轻症甲型H1N1流感症状轻,预后好,麻杏石甘汤联合奥司他韦治疗轻症甲型H1N1流感有缩短热程的作用,安全可行。     

山东省甲型H1N1流感隐性感染者抗体调查

[目的]了解在山东省流行性感冒流行季节,甲型H1N1流感病毒的隐性感染状况,分析我省甲型H1N1流感病毒疫情趋势。[方法]2009年12月在我省部分医院门诊检验室和自愿献血站分年龄组采集就诊者和献血者血清400份,采用血凝抑制试验(HI试验)检测甲型H1N1流感抗体,观察人群对甲型H1N1流感病毒的感染状况。[结果]调查400人特定人群,甲型H1N1流感抗体阳性者19人,其中2名抗体阳性者注射了甲型H1N1流感疫苗,隐性感染率为4.25%。18～55岁年龄组隐性感染率最高(9.00%),不同年龄组间隐性感染率的差异有统计学意义(P0.05),不同性别间的差异无统计学意义(P0.05),有无流感样症状者抗体阳性率高于无流感样症状者,差异有统计学意义(P0.05)。[结论]我省甲型H1N1流感在人群中隐性感染率较低,人群主动免疫力低下。     

湘西自治州甲型H1N1流感血清流行病学调查

目的 了解湘西自治州人群甲型H1N1流感病毒感染状况和免疫水平,分析流感流行趋势,为制定针对性的防治措施提供依据.方法 采用多阶段分层随机抽样方法,于2010年1月4月8月共选取675人进行问卷调查,并采集血液标本进行甲型H1N1流感病毒血凝抗体检测.结果 在不同季节,不同职业人群中H1抗体阳性率不同(P＜0.05),同时在出现过急性呼吸道症以及接种过甲型H1N1流感疫苗的人群中H1抗体阳性率相对较高(P＜0.05).H1抗体GMT呈现季节性变化(P＜0.05),在不同年龄,不同职业人群中抗体水平大小差异有统计学意义(P＜ 0.05,P＜ 0.01).调查还发现发现出现过急性呼吸道症人群中抗体GMT和中位数高于未出现呼吸道症状者(P＜ 0.001);接种过甲型H1N1流感疫苗者抗体GMT和中位数也同样高于未接种者(P＜ 0.001).在不同性别和民族人群中,抗体的阳性率和水平大小无统计学差异.结论 目前湘西地区甲型H1N1流感已经得到有效控制,但鉴于人群中保护性抗体水平季节性变化,下一阶段重点是定期开展快速的血清学监测,并且继续对高危人群实施甲型H1N1流感疫苗接种.     

中学生接种甲型H1N1流感疫苗保护效果的评价

目的 了解中学生接种甲型H1NI流感疫苗的保护效果.方法 采用非随机对照临床试验方法,选择8所中学14 883名学生,分甲型H1N1流感疫苗接种组6334人,对照组(未接种)8549人,随访观察一个流行周期(6个月),比较两组流感样病例、甲型H1N1流感病例、季节性流感病例的发生率.结果 所有研究对象累计观察7441.75人年.接种组流感样病例发病密度为21.47/1000人年,低于对照组(22.69/1000人年),差异无统计学意义(P>0.05);接种组甲型H1N1流感发病密度为0,低于对照组1.64/1000人年,两者率差为-1.64/1000人年(95%CI:-3.04～-0.23),差异有统计学意义(P=0.010);接种组流感病毒核酸阳性病例发病密度为6.63/1000人年,低于对照组(7.02/1000人年),差异无统计学意义(P>0.05);接种组乙型流感发病密度为6.63/1000人年,高于对照组(5.38/1000人年),差异无统计学意义(P>0.05).结论 学生大规模接种甲型H1N1流感疫苗能有效预防甲型H1N1流感,其保护效果良好,但对于其他季节性流感可能无交叉保护作用.

Abstract：

Objective To evaluate the epidemiological effects of vaccine immunization program related to A(H1N1)influenza in the middle school students.Methods Non-randomized clinical trial was designed to assess the A(H1N1)influenza vaccine on its efficacy.14883 students from 8 middle schools in Zhejiang province were recruited and classified into vaccinated or control groups,based on the status of immunization with A(H1N1)influenza vaccine.All subjects were followed up through one epidemic period(6 months)and the incidence rates of influenza-like illnesses,A(H1N1)influenza,and seasonal influenza in these two groups were compared to evaluate the efficacy of the vaccine.Results There were 6334 subjects in the vaccinated group and 8549 in the control group.7441.75 person-years were followed from these two groups.The incidence rate of A (H1N1)influenza in vaccinated group was 1.64‰ per person-year,lower than that of the control group.The rate difference(RD)was-1.64‰ per person-year(95% confidence interval value from-3.04‰ to-0.23‰ per person-year),and the difference was significant(P=0.010).The incidence rate of influenza-like illnesses in vaccinated group was 21.47‰ per person-year,lower than that of the control group(22.69‰ per person-year)and the diffefence was not significant(P>0.05).The incidence rate of B influenza in vaccinated group was 6.63‰ per person-year,higher than that of control group(7.02‰ per person-year)but the difference was not significant(P>0.05).Conclusion This vaccine demonstrated a good epidemiological effect against the A(H1N1)influenza virus infection,observed through a student-immunization program.The cross-protection effect against the influenza-like illnesses and other seasonal influenzas was not noticed in this study.     

Optimal vaccination strategies for 2009 pandemic H1N1 and seasonal influenza vaccines in humans

A randomized clinical trial was conducted to assess whether the immunogenicity of seasonal and pandemic (H1N1/09) influenza vaccines is affected by the order of vaccine administration. 151 healthy adult volunteers were randomized into three groups. All groups received one dose (15 μg haemagglutinin) each of a pandemic H1N1 vaccine and a seasonal trivalent vaccine. Group 1 received the pandemic H1N1 vaccine first, followed by the seasonal vaccine 21 days later. Group 2 received vaccinations in vice versa and Group 3 received both vaccines simultaneously. Post-vaccination blood samples were collected to determine the immunogenicity by hemagglutination-inhibition (HI), microneutralization (MN), and B cell ELISPOT assays. All three vaccination strategies were well-tolerated and generated specific immune responses. However, we found a significant difference in magnitude of antibody responses to pandemic H1N1 between the three groups. Pre- or co-vaccination with the seasonal flu vaccine led to a significant reduction by 50% in HI titre to pandemic H1N1 virus after pandemic vaccination. Pre- or co-vaccination of pandemic H1N1 vaccine had no effect on seasonal flu vaccination. MN and ELISPOT assays showed a similar effect. Vaccination with pandemic H1N1 vaccine first is recommended to avoid an associated inhibitory effect by the seasonal trivalent flu vaccine. Clinical_Trials identifier: NCT01008137.     

Pandemic influenza A/H1N1 vaccine administered sequentially or simultaneously with seasonal influenza vaccine to HIV-infected children and adolescents

In order to evaluate the immunogenicity, safety and tolerability of the 2009 A/H1N1 MF59-adjuvanted influenza vaccine administered sequentially or simultaneously with seasonal virosomal-adjuvanted influenza vaccine to HIV-infected children and adolescents, 36 HIV-infected children and adolescents, and 36 age- and gender-matched healthy controls were randomised 1:1 to receive the pandemic vaccine upon enrolment and the seasonal vaccine one month later, or to receive the pandemic and seasonal vaccines simultaneously upon enrolment. Seroconversion and seroprotection rates against the pandemic influenza A/H1N1 virus were 100% two months after vaccine administration in both groups, regardless of the sequence of administration. Geometric mean titres against pandemic and seasonal antigens were significantly higher when the seasonal and pandemic vaccines were administered simultaneously than when the seasonal vaccine was administered alone. Local and systemic reactions were mild and not increased by simultaneous administration. In conclusion, the 2009 pandemic influenza A/H1N1 MF59-adjuvanted vaccine is as immunogenic, safe and well tolerated in HIV-infected children and adolescents as in healthy controls. Its simultaneous administration with virosomal-adjuvanted seasonal antigens seems to increase immune response to both pandemic and seasonal viruses with the same safety profile as that of the pandemic vaccine alone. However, because this finding cannot be clearly explained by an immunological viewpoint, further studies are needed to clarify the reasons of its occurrence.     

A follow-up comparative safety analysis of pandemic H1N1 vaccination during pregnancy and risk of infant birth defects among U.S. military mothers

ObjectiveTo update a previous assessment of birth defects among infants born to active duty U.S. military mothers who received the 2009–2010 pandemic H1N1 vaccine, in comparison to the 2008–2009 seasonal influenza vaccine, during pregnancy. Here, we updated the previous comparative analyses with a more refined definition for birth defects using an additional year of follow-up data from both inpatient and outpatient medical encounters.MethodsThe study population included 15,510 live born infants born to active duty mothers vaccinated during pregnancy with either the 2009–2010 pandemic H1N1 vaccine (n = 9033) or the 2008–2009 seasonal influenza vaccine (n = 6477). Birth defect cases were defined as those infants who received a birth defect diagnosis on one inpatient record or two outpatient records on different days within the first year of life. Multivariable logistic regression models were conducted to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for the association between birth defects and maternal vaccination during pregnancy with pandemic H1N1 vaccine versus seasonal influenza vaccine.ResultsInfants born to mothers vaccinated during pregnancy with the pandemic H1N1 vaccine, versus the seasonal influenza vaccine, were not at increased odds of birth defects in univariable (OR: 1.13, 95% CI: 0.95–1.34) or multivariable (OR: 1.14, 95% CI: 0.96–1.35) models. Findings were not significant when further limited to first trimester exposure. Multivariable models were adjusted for infant sex and plurality; maternal age, race/ethnicity, marital status, service branch, military rank, and occupation; timing of vaccination; and receipt of vaccination(s) not routinely recommended during pregnancy.ConclusionComparable to our previous analyses assessing birth defects diagnosed at birth, no significant association was found between the pandemic H1N1 vaccination during pregnancy and birth defects, versus the seasonal influenza vaccine. These findings are reassuring and provide additional support for H1N1-containing seasonal influenza vaccination during pregnancy.     

Pandemic H1N1 vaccine requires the use of an adjuvant to protect against challenge in naïve ferrets

In the context of an A/H1N1 influenza pandemic situation, this study demonstrates that heterologous vaccination with an AS03-adjuvanted 2008/2009 seasonal trivalent and pandemic H5N1 monovalent split vaccine conferred partial protection in influenza-naïve ferrets after challenge with the influenza pandemic H1N1 A/The Netherlands/602/09 virus. Further, unlike saline control and non-adjuvanted vaccine, it was shown that immunization of naïve ferrets with an AS03-adjuvanted pandemic H1N1 A/California/7/09 influenza split vaccine induced increased antibody response and enhanced protection against the challenge strain, including significant reduction in viral shedding in the upper respiratory tract and reduced lung pathology post-challenge. These results show the need for vaccination with the adjuvanted vaccine to fully protect against viral replication and influenza disease in unprimed ferrets.     

Vaccination against pandemic influenza A/H1N1 among healthcare workers and reasons for refusing vaccination in Istanbul in last pandemic alert phase

Coverage of the HCWs as target population is one of the important determinants for the impact of vaccination. To determine the vaccination against the pandemic influenza A/H1N1 among HCWs, we conducted a cross-sectional questionnaire survey in a public hospital in Istanbul from December 7 to December 22, 2009. Out of total 941 HCWs 718 (76.3%) completed the questionnaires. Nearly one-fourth (23.1%) of the participants were vaccinated against pandemic influenza A/H1N1. Occupation (being a doctor), receiving seasonal influenza vaccine in 2009, agreement with safety of pandemic influenza A/H1N1 vaccine and being comprehend that HCWs have a professional responsibility for getting vaccinated was the strongest independent predictive factor for accepting the pandemic influenza A/H1N1 vaccine (p < .0001). The most frequent reasons for refusing pandemic vaccine were fear of side effects and doubts about vaccine efficacy. Among HCWs 59.6% were recommending pandemic influenza vaccination to a patient even if indicated. In conclusion vaccination against pandemic influenza A/H1N1 is insufficient among HCWs. Misinformed or inadequately informed HCWs are important barrier to pandemic influenza vaccine coverage of the general public also. Educational campaigns concerning HCWs should include evidence based and comprehensible information about possible adverse effects and their incidence besides the advantages of vaccine.     

2010年长沙市甲型H1N1流感大流行血清学流行病学调查

目的掌握2010年长沙市甲流流行期间不同时点及人群甲型H1N1型流感血清流行病学特征。方法 2010年1月、3月、8月使用多阶段随机抽样方法在全市5个区,按照0~、6~、16~、25~和60~岁5个年龄组随机抽取一定数量的研究对象开展三次横断面调查,每次均对调查对象进行问卷调查,并采集静脉血进行甲型H1N1流感血凝抑制试验。结果 5个年龄组人群中,6~岁组和16~岁组甲流血清抗体阳性率都随着时间的推移呈现下降趋势,以6~岁组的下降幅度较大,其抗体滴度几何均数(GMT)下降幅度也较大。6个职业组人群中,学生和医务人员组甲流血清抗体阳性率都随着时间的推移呈现下降趋势,学生组下降幅度较大。不同性别间血清抗体阳性率和GMT差异均无统计学意义(P0.05)。综合三次调查结果,接种甲流疫苗后,人群的甲流血清抗体阳性率达到55.53%,为未接种流感疫苗人群的2.15倍;抗体GMT达到44.62,为未接种甲流疫苗人群的3.74倍。结论 2010年长沙市甲流流行趋势趋于缓和,初步形成免疫屏障;学生和医务人员是感染甲流的高风险人群;接种甲流疫苗后人群有较高的抗体阳性率,但是抗体水平下降较快;接种甲流疫苗对人群有一定的保护作用,应加强对60岁及以上人群甲流疫苗的接种和补种。