Influence of parent characteristics and disease outcome framing on HPV vaccine acceptability among rural,Southern women

Objective A new prophylactic vaccine protects against infection with HPV types that cause many cervical cancers and genital warts. This study explored the impact of framing the vaccine’s benefits, with respect to the disease outcome being prevented, on women’s HPV vaccination intentions for themselves and for an adolescent daughter. Methods A cross-sectional study was conducted in a rural North Carolina area with a high cervical cancer mortality rate. A questionnaire was administered among female attendees of a low-income public clinic and a private OB/GYN office. Data were analyzed using a generalized estimable model. Results Women reported high intentions to vaccinate against HPV. Women reported higher intentions to vaccinate adolescent daughters than themselves, and this relationship varied by how the HPV vaccine was framed (preventing HPV, cervical cancer, or genital warts). Older women reported lower vaccination intentions than younger women. Conclusions Rural women, especially those who are younger, may be more accepting of the HPV vaccine when it is framed as a cervical cancer vaccine. Messages to mothers about the HPV vaccine for their daughters might be made more effective by framing the vaccine in terms of cancer and sexually transmitted disease prevention.     

Awareness of Turkish Female Adolescents and Young Women about HPV and their Attitudes Towards HPV Vaccination

Background: The aim of the study was to assess the knowledge about HPV and HPV vaccines and attitudestowards vaccination among the females aged 9-24 years in Turkey. Materials and Methods: Self-administeredquestionnaires were filled out individually by the participants covering demographic information, knowledgeabout HPV infection and HPV vaccines, attitudes towards vaccination, and the perceptions of them about theirparental attitudes about vaccination. Results: Of the 408 subjects participating in the study, 41.6% (n=170) hadheard of HPV. Thirty-three percent (n=136) knew the causal relationship between HPV and cervical cancer.Only 27.9% (n=114) of them knew that HPV vaccines can prevent cervical cancer. Eleven percent (n=46) of thefemales participating in the study were willing to be vaccinated, and only 1.4% (n=6) were already vaccinated atthe current time. The main reason listed among the participants who were not willing to be vaccinated was lackof information. Conclusions: Awareness and knowledge of Turkish female adolescents and young women aboutHPV, relation with cervical cancer and prevention of cervical cancer by Pap smear and vaccine are still limited.If the most important barrier to vaccination, which is reported as lack of information, were to be addressed, itwould greatly impact the decision-making and vaccine acceptance.     

Knowledge of Pap smear, HPV and the HPV vaccine and the acceptability of the HPV vaccine by Thai women

Aims: The primary prevention for cervical cancer, a human papilloma virus (HPV) vaccine, has been available in Thailand for almost 3 years. The present study evaluates knowledge about the Papanicolaou (Pap) smear, HPV and the HPV vaccine and focuses on identifying predictors for the acceptability of the HPV vaccine. Methods: A sample of 764 women attending the gynecology clinic at Ramathibodi Hospital, Bangkok, was asked to answer a questionnaire on their personal background, their knowledge of the Pap smear and HPV and the HPV vaccine and the acceptability of the HPV vaccine for themselves and their daughters. Results: Knowledge of the Pap smear (96%) is higher than that of HPV (41%) and the HPV vaccine (36%). Only 40% of participants had previously heard about HPV. The acceptability of the HPV vaccine for participants and their daughters was high, 77% and 84%, respectively. Knowing about HPV increases acceptance for the HPV vaccine (adjusted OR = 1.7, 95% CI = 1.2–2.5, in the participants and OR = 2.3, 95% CI = 1.5–3.6 in their daughters). Participants younger than 45 years old (OR = 2.3 and 95% CI = 1.6–3.4 for themselves; OR = 2.2 and 95% CI = 1.4–3.3 for their daughters) were more likely to accept the vaccination than those aged 45 years old and above. Conclusion: Knowledge about HPV and the HPV vaccine is generally poor in Thai women. However, the acceptability of the HPV vaccine is good. Knowing about HPV and age under 45 years predict the acceptability of the HPV vaccine.     

Practice of HPV Vaccine and Associated Factors among School Girls in Melaka,Malaysia

Objective: The objective of this study is to determine the practice and associated factors of HPV vaccineamong school girls in Melaka, Malaysia. Methodology: A total number of 612 secondary school girls participatedin this study. The questionnaire consists of 38 questions which included 3 sections. The first section is about sociodemography.The Second section is about knowledge and awareness of HPV vaccines. The third section is aboutpractices with associated barriers of HPV vaccination. Verbal consent was obtained from all participants, anddata were analyzed using SPSS 13. Results: A total number of 612 secondary school girl students participated inthis study. The mean age was 13.93±SD (1.09); minimum age was 13 years old and maximum was 17 years old.The majority of them was Malay, from rural areas and had a family monthly income of RM 3000 or less (91.8%,53.1%, 69.6%; respectively). The majority of the parents of the school girls were with secondary educationlevel (56.4%). The majority of the participants did not have a family history of cervical cancer (99.0%). Theprevalence of HPV vaccination was 77.9% among school girls in Melaka. The majority of the participants werevaccinated in their schools (77.0%). About 69% knew about cervical cancer and 77.6% had ever heard aboutHPV vaccine. Regarding the factors that influence the practice of uptake HPV vaccine, they were age, race,income, parents’ education, knowledge about cervical cancer, heard about HPV vaccine and place of getting thevaccine (p<0.001). Conclusion: The prevalence of HPV vaccine among school girls is high. Age, race, income,parents’ education, knowledge about cervical cancer, heard about HPV vaccine and place of getting the vaccinewere the significant factors that influence the practice of uptake HPV vaccine among school girls.     

Knowledge of cervical cancer and HPV vaccine post- vaccination among mothers and daughters in Vietnam

Background: Limited human papillomavirus (HPV) related knowledge might be a barrier to future vaccineacceptance. From 2008-2010, PATH conducted an HPV vaccination demonstration project in partnership withthe government immunization program in Vietnam, which included awareness campaigns prior to vaccination.Objective: To assess and compare knowledge and attitudes about cervical cancer and HPV vaccines betweenmothers and daughters, and whether knowledge was associated with vaccination status. Methods: We analyzedHPV-related knowledge and attitude data from mother-daughter paired responses to a cross-sectional householdsurvey. After parents completed the survey, daughters were asked the same questions. We calculated the frequencyof responses for each question and devised a scaled composite measure for knowledge. Results: Participantsbelieved they had received enough information about cervical cancer and HPV vaccines and it was sufficient tomake a decision about vaccination. Fifty percent of the participants knew HPV causes cervical cancer and 80%knew the HPV vaccine prevented cervical cancer. Mothers had more knowledge about cervical cancer and HPVinfection (p<0.01), compared to daughters, who had more vaccine specific knowledge (p<0.01). However, thetotal mean knowledge score was similar for the groups. Girls not fully vaccinated had a lower mean knowledgescore than fully vaccinated girls (p<0.001). Conclusions: Our results suggest that the purpose of the HPVvaccine was clearly messaged; however, some misconceptions about cervical cancer and HPV still exist. Limitedknowledge about the magnitude of cervical cancer, HPV as a cause of cervical cancer, and HPV vaccines mayhave contributed to incomplete vaccination.     

National HPV Immunisation Programme: Knowledge and Acceptance of Mothers Attending an Obstetrics Clinic at a Teaching Hospital,Kuala Lumpur

Background: Introduction of the HPV vaccine is a forefront primary prevention method in reducing theincidence of carcinogenic human papillomavirus (HPV) and cervical cancer. The Malaysia government hasimplemented the National HPV immunisation programme since 2010, supplying HPV vaccine free to targeted13 year olds. This study aimed to explore the level of knowledge among mothers on cervical cancer, HPV,HPV vaccine and National HPV (NHPV) immunisation programme since its’ implementation. It also assessedacceptance of mothers towards HPV vaccine being administered to their daughter, son or themselves. Materialsand Methods: A cross sectional study was conducted on 155 respondents using self-administered questionnaires;conducted in December 2012 at the Obstetrics and Gynaecology Clinic in a teaching hospital in Kuala Lumpur.Respondents were selected using a multistage sampling technique. Results: A response rate of 100% was obtained.Overall, 51.0% of mothers had good knowledge, with 55% having good knowledge of cervical cancer, 54.2%for both HPV and the National HPV immunisation programme and 51.0% for the HPV vaccine. Regressionanalyses showed that ethnicity was associated with knowledge on cervical cancer (p=0.003) while education wasassociated with knowledge on HPV (p=0.049). Three factors are associated with knowledge of the National HPVimmunisation programme; ethnicity (p=0.017), mothers’ education (p=0.0005) and number of children (p=0.020).The acceptance of HPV vaccine to be administered among daughter was the highest at 87.1%, followed by formothers themselves at 73.5%, and the least is for sons 62.6%. Conclusions: This study found that the overalllevel of knowledge was moderate. Adequate information on cervical cancer, HPV, HPV vaccination and theNational HPV immunisation programme should be provided to mothers in order to increase acceptance of theHPV vaccine which can reduce the disease burden in the future.     

Knowledge and Awareness of Human Papillomavirus (HPV), Cervical Cancer and HPV Vaccine among Women in Two Distinct Nepali Communities

Background: This study assessed human papillomavirus (HPV), cervical cancer, and HPV vaccine knowledgeand awareness among women in two sub-populations in Nepal - Khokana, a traditional Newari village in theLalitpur District about eight kilometers south of Kathmandu, and Sanphebagar, a village development committeewithin Achham District in rural Far-Western Nepal. Methods: Study participants were recruited during healthcamps conducted by Nepal Fertility Care Center, a Nepali non-governmental organization. Experienced staffadministered a Nepali language survey instrument that included questions on socio-demographics, reproductivehealth and knowledge on HPV, cervical cancer, and the HPV vaccine. Results: Of the 749 participants, 387 (51.7%)were from Khokana and 362 (48.3%) were from Sanphebagar. Overall, 53.3% (n=372) of women were awareof cervical cancer with a significant difference between Khokana and Sanphebagar (63.3% vs 43.0%; p=0.001).Overall, 15.4% (n=107) of women had heard of HPV and 32% (n=34) of these women reported having heard ofthe HPV vaccine. If freely available, 77.5% of the women reported willingness to have their children vaccinatedagainst HPV. Factors associated with cervical cancer awareness included knowledge of HPV (Khokana: OddsRatio (OR)=24.5; (95% Confidence Interval (CI): 3.1-190.2, Sanphebagar: OR=14.8; 95% CI: 3.7-58.4)) andsexually transmitted infections (Khokana: OR=6.18; 95% CI: 3.1-12.4; Sanphebagar: OR=17.0; 95% CI: 7.3-39.7) among other risk factors. Conclusions: Knowledge and awareness of HPV, cervical cancer, and the HPVvaccine remains low among women in Khokana and Sanphebagar. Acceptance of a freely available HPV vaccinefor children was high, indicating potentially high uptake rates in these communities.     

HPV Vaccine Knowledge and Beliefs Among Cambodian American Parents and Community Leaders

Background: The cervical cancer incidence rate among Cambodian American women is 15.0 per 100,000,compared to 7.7 per 100,000 among non-Latina white women. HPV infection has been identified as a universalrisk factor for cervical cancer. The HPV vaccine was recently approved in the United States for females aged 9-26 years. There is little information about HPV vaccination knowledge and beliefs in Southeast Asian communities.Methods: We conducted 13 key informant interviews with Cambodian community leaders, as well as four focusgroups with Cambodian parents (37 participants). Two of the focus groups included fathers and two of the focusgroups included mothers. Interview and focus group questions addressed HPV vaccine barriers and facilitators.Results: Participants had limited knowledge about HPV infection and the HPV vaccine. Barriers to HPVvaccination included a lack of information about the vaccine, as well as concerns about vaccine safety, effectiveness,and financial costs. The most important facilitators were a health care provider recommendation for vaccinationand believing in the importance of disease prevention. Discussion: Future cervical cancer control educationalprograms for Cambodians should promote use of the HPV vaccine for age-eligible individuals. Health careproviders who serve Cambodian communities should be encouraged to recommend HPV vaccination.     

HPV communication: review of existing research and recommendations for patient education

The potential for human papillomavirus (HPV) DNA testing in cervical cancer prevention programs has been a topic at the forefront of cervical cancer policy discussions in recent years. To prevent some of the anxiety and psychological distress often experienced on HPV diagnosis and during the period of management, mass patient education must accompany the incorporation of HPV DNA testing into screening protocols. To contribute to a growing body of work that provides an empiric basis for development of effective counseling messages about HPV and HPV testing, this paper highlights women's most common information gaps and psychosocial concerns and describes the different perspectives offered by women's usual sources of information about HPV, including the crucial role of the clinical community in creating a shared decision making environment in which screening decisions and results can be discussed.     

Knowledge towards HPV infection and HPV vaccines among Syrian mothers

Cervical cancer is caused by HPV infection and can be prevented by early vaccination. Objective: To assess Syrian women’s level of knowledge and determinants of good knowledge of cervical cancer, HPV infection and its vaccines. Methods: A cross sectional survey was undertaken among mothers with daughters in sixth grade classes enrolled in primary schools in Aleppo city, Syria. Samples were selected through cluster sampling and data collected using a self-administered questionnaire. Results: Less than a third of the mothers had heard of HPV infection and vaccines against cervical cancer and levels of knowledge were generally low. Good knowledge was associated with high education level, higher family monthly income, having few - less than four children, positive history of cervical cancer screening, and working or having relatives working in the medical field. The main source of information was television and few reported health care providers as a source of knowledge on HPV infection and vaccine. Conclusion: Since knowledge of HPV infection and its connection with cervical cancer and its vaccine are low, more efforts must be made to educate Syrians prior to introduction of any HPV vaccination programme. Public health efforts must focus on educating mothers, the public as well as health care providers.     

A comprehensive natural history model of HPV infection and cervical cancer to estimate the clinical impact of a prophylactic HPV-16/18 vaccine

The object of our study is to project the impact of a prophylactic vaccine against persistent human papillomavirus (HPV)-16/18 infection on age-specific incidence of invasive cervical cancer. We developed a computer-based mathematical model of the natural history of cervical carcinogenesis to incorporate the underlying type-specific HPV distribution within precancerous lesions and invasive cancer. After defining plausible ranges for each parameter based on a comprehensive literature review, the model was calibrated to the best available population-based data. We projected the age-specific reduction in cervical cancer that would occur with a vaccine that reduced the probability of acquiring persistent infection with HPV 16/18, and explored the impact of alternative assumptions about vaccine efficacy and coverage, waning immunity and competing risks associated with non-16/18 HPV types in vaccinated women. The model predicted a peak age-specific cancer incidence of 90 per 100,000 in the 6th decade, a lifetime cancer risk of 3.7% and a reproducible representation of type-specific HPV within low and high-grade cervical precancerous lesions and cervical cancer. A vaccine that prevented 98% of persistent HPV 16/18 was associated with an approximate equivalent reduction in 16/18-associated cancer and a 51% reduction in total cervical cancer; the effect on total cancer was attenuated due to the competing risks associated with other oncogenic non-16/18 types. A vaccine that prevented 75% of persistent HPV 16/18 was associated with a 70% to 83% reduction in HPV-16/18 cancer cases. Similar effects were observed with high-grade squamous intraepithelial lesions (HSIL) although the impact of vaccination on the overall prevalence of HPV and low-grade squamous intraepithelial lesions (LSIL) was minimal. In conclusion, a prophylactic vaccine that prevents persistent HPV-16/18 infection can be expected to significantly reduce HPV-16/18-associated LSIL, HSIL and cervical cancer. The impact on overall prevalence of HPV or LSIL, however, may be minimal. Based on the relative importance of different parameters in the model, several priorities for future research were identified. These include a better understanding of the heterogeneity of vaccine response, the effect of type-specific vaccination on other HPV types and the degree to which vaccination effect persists over time.     

Human papillomavirus and vaccination: knowledge, attitudes, and behavioural intention in adolescents and young women in Italy

This study assesses knowledge, attitudes, and behavioural intention towards human papillomavirus (HPV) infection and vaccination in a random sample of 1348 adolescents and young women aged 14-24 years in Italy. A self-administered anonymous questionnaire covered demographics; knowledge about HPV infection, cervical cancer, and HPV vaccine; the perceived risk for contracting HPV infection and/or for developing cervical cancer, the perceived benefits of a vaccination to prevent cervical cancer, and willingness to receive an HPV vaccine. Only 23.3% have heard that HPV is an infection of the genital mucosa and about cervical cancer. Those older, with at least one parent who is a health care professional, with personal, familiar, or friendly history of cervical cancer, and having underwent a health checkup in the last year with information about HPV vaccination were significantly more knowledgeable. Risk perception scores (range: 1-10) of contracting HPV infection and of developing cervical cancer were 5.8 and 6.5. Older age, not having a parent who is a health care professional, having had a personal, familiar, or friendly history of cervical cancer, and need of additional information were predictors of the perceived susceptibility of developing cervical cancer. The vast majority professed intent to receive an HPV vaccine and the significant predictors were having at least one parent who is a health care professional, a high perceived risk of contracting HPV infection and of developing cervical cancer, and a high belief towards the utility of a vaccination for preventing cervical cancer. Knowledge about HPV infection and cervical cancer should be improved with more attention to the benefit of HPV vaccination.     

Vaccination against Human Papilloma Virus (HPV): Epidemiological Evidence of HPV in Non-genital Cancers

Recently, the vaccine against human papillomavirus (HPV) was introduced in the national vaccination programmes of several countries worldwide. The established association between HPV and the progression of cervical neoplasia provides evidence of the expected protection of the vaccine against cervical cancer. During the last two decades several studies have also examined the possible involvement of HPV in non-genital cancers and have proposed the presence of HPV in oesophageal, laryngeal, oropharyngeal, lung, urothelial, breast and colon cancers. The possible involvement of HPV in these types of cancer would necessitate the introduction of the vaccine in both boys and girls. However, the role of HPV in the pathogenesis of these types of cancer has yet to be proven. Moreover, the controversial evidence of the possible impact of the vaccination against HPV in the prevention of non-genital cancers needs to be further evaluated. In this review, we present an overview of the existing epidemiological evidence regarding the detection of HPV in non-genital cancers.     

Characterization of HPV subtypes not covered by the nine-valent vaccine in patients with CIN 2-3 and cervical squamous cell carcinoma

Background: As the second most common female malignant tumor, cervical cancer is also one of the most preventable and avoidable cancers. The World Health Organization has launched a global plan to accelerate the elimination of cervical cancer. Therefore, in the era of postvaccine, the role of HPV subtypes in cervical precancerous lesions and cervical cancer that are not covered by vaccine should be further discussed. The purpose of this study was to explore the role of HPV subtypes not covered by the nine-valent vaccine in high-grade cervical precancerous lesions and cervical cancer. Materials and methods: A retrospective analysis was performed on the clinical data of 5220 patients with an HPV infection who were diagnosed and treated in the Department of Gynecology of Shanghai General Hospital between October 2016 and February 2020. In addition, the clinical characteristics of the biopsy results of 470 cases of cervical intraepithelial neoplasia (CIN) 2-3 and 205 cases of cervical squamous cell carcinoma were analyzed. Results: Among patients with HPV subtype infection not covered by the nine-valent vaccine, univariate analysis showed that compared with patients with CIN 2-3, age ≥ 50, not using condom and TCT reported as ASC-H were risk factors for cervical squamous cell carcinoma (P < 0.05). The detection rates of HPV subtype not covered by the nine-valent vaccine in CIN 2-3 and cervical squamous cell carcinoma patients were 7.23% and 6.34%, respectively. Conclusion: In patients with CIN 2-3 and cervical squamous cell carcinoma, the infection rates of HPV subtype not covered by the nine-valent vaccine were 7.23% and 6.34%, respectively. With the increasing popularity of the vaccine, the infection rates of the corresponding HPV subtype decreased; however, HPV subtype infection not covered by the nine-valent vaccine should not be ignored.     

Prevalence of HPV types in cervical specimens from an integrated healthcare delivery system: baseline assessment to measure HPV vaccine impact

Purpose

Two human papillomavirus (HPV) vaccines are available to prevent cervical cancer. One early measure of HPV vaccine impact would be a reduction in vaccine-related HPV types (HPV 6, 11, 16, or 18, or HPV 16, 18) in cervical samples from young women. We aimed to assess feasibility of specimen collection and baseline HPV prevalence in an integrated healthcare delivery system.

Methods

Residual cervical specimens collected during routine cervical cancer screening (2006–2008) were retained consecutively from eligible females aged 11–29 years, stratified by age group. Specimens were evaluated for 37 HPV genotypes using the Roche Linear Array assay.

Results

Of 10,124 specimens submitted, 10,103 (99 %) were adequate for HPV testing. Prevalence of HPV 6, 11, 16, or 18 genotype was 11.4 % overall and was the highest in the youngest age group (18.1 % in the 11–19-year-olds, 12.5 % in the 20–24-year-olds, and 7.0 % in the 25–29-year-olds).

Conclusions

HPV types 6, 11, 16, or 18 prevalence could be measured over time to assess early HPV vaccine impact using residual specimens from an integrated healthcare delivery system, particularly if sampling focused on young women.     

HPV Vaccination: An Underused Strategy for the Prevention of Cancer

Human papillomavirus (HPV) vaccination prevents cervical, head and neck, and anogenital cancers. However, global HPV vaccine coverage falls short of global targets and has seen unexpected and dramatic declines in some countries. This paper synthesizes the impact of HPV on the global burden of cancer and the potential benefit of HPV vaccination. Approximately 5% of the world’s cancers are specifically attributed to HPV. While the greatest global burden of HPV is cervical cancers in low- and middle-income countries, HPV-associated head and neck cancers are increasing in high-income countries and have surpassed cervical cancer as the primary HPV-associated cancer in some countries. Therefore, it is also critical to improve gender-neutral HPV vaccination. Understanding the modifiable drivers of vaccine acceptance and uptake is important for increasing HPV vaccination. The Behavioural and Social Drivers of Vaccination framework is broadly applied to identify key factors associated with HPV vaccination including domains concerning practical issues, motivation, social processes, and thinking and feeling. Among the behavioural strategies available to reduce the incidence and mortality of cancer, increasing HPV vaccination stands out as having unrealized potential to prevent disease, financial cost, and psychological distress. An understanding of the shifting burden of HPV and the factors associated with vaccination can be leveraged to regularly measure these factors, develop interventions to promote vaccine uptake, and improve global HPV vaccine coverage. Future research in diverse contexts is necessary to investigate the barriers and facilitators of global HPV vaccination.     

人乳头瘤病毒疫苗防治宫颈癌研究的新进展

宫颈癌的发病率在女性恶性肿瘤居第二位,人乳头状瘤病毒(HPV)感染已被证实为宫颈癌发生的主要因素,采用HPV疫苗防治HPV感染和宫颈癌是最根本的病因治疗方法,其中HPV疫苗分为预防性疫苗和治疗性疫苗两大类,本文综述了近几年关于HPV疫苗的研究成果.     

Barriers,Attitudes and Clinical Approach of Lebanese Physicians Towards HPV Vaccination; A Cross- Sectional Study

Objectives: HPV infection is associated with the development of cervical and oropharyngeal cancer. HPV vaccination prevents cervical cancer, but is still not part of Lebanon’s routine vaccination schedule. As such, understanding physicians’ practice towards HPV vaccination is essential. Material and Methods: We conducted a cross-sectional study in Greater Beirut, Lebanon to assess the barriers, attitudes and clinical approach of Lebanese physicians towards HPV vaccination. We also aimed to analyze the factors associated with physicians’ barriers to HPV vaccination. Results: In total, 228 physicians completed the survey. Our results show that physicians and parents consider the cost of HPV vaccination to be a main barrier (58.9% and 80.7% respectively). Also, parents tend to have concerns about vaccine safety (78.1%), efficacy (68.6%), and lack education concerning HPV infection (81.8%). Furthermore, female physicians tend to have fewer barriers when compared to male physicians (aOR = 0.39; p-value = 0.007). Additionally, physicians who completed residency programs in the USA also showed fewer barriers when compared to physicians who completed Lebanese residency programs (aOR = 0.24; p-value = 0.040). Finally, physicians with higher knowledge score have fewer barriers when compared to those with lower knowledge scores (aOR = 0.42; p-value = 0.018). Conclusions: Physician gender, residency program and level of knowledge play a role in HPV vaccine barriers and recommendation in Lebanon. Future improvements in cost and awareness about HPV might improve vaccination rates. Creating uniform practices towards HPV vaccine is warranted to improve patient care.     

预防性 HPV 疫苗的临床应用进展及思考

宫颈癌是女性生殖系统最常见的恶性肿瘤,并且高危型人乳头瘤病毒（human papillomavirus, HPV）持续感染与宫颈癌的密切关系已经得到流行病学及临床研究证实。因此,HPV 疫苗在预防 HPV 持续感染及宫颈相关病变等方面备受瞩目。本文对目前美国 FDA 批准上市的3种预防性疫苗的临床应用进展进行综述,同时列举出一些尚存在争议的问题,旨在引起人们的重视及共同思考。