Overview of the Efficacy of Human Papillomavirus Virus Vaccines

Human papillomavirus (HPV) infection is the main cause of cervical cancer and major viruses related to carcinogenesis in various malignant diseases such as cervical cancer, vaginal cancer, vulvar cancer, anal cancer, and head and neck cancer. Cervical cancer is the second most prevalent female cancer in the world and the fourth in Korea. Prophylactic HPV vaccines in widespread use include the used in South Korea to prevent cervical cancer are bivalent (2-valent HPV vaccine; Cervarix), quadrivalent (4-valent HPV vaccine; Gardasil), and nonavalent (9-valent HPV vaccine; Gardasil9). Since HPV vaccines the first approval in 2006, 115 countries have include HPV vaccines in their national immunization programs, that its preventive effect is as much as 70%, and that the incidence of high-risk types of HPV has gradually decreased. According to HPV cohort studies in Korea, about 26% of adult women have an HPV vaccination history and show a low incidence of HPV-16/18 genotypes compared to unvaccinated women. In the countries that National Immunization Programs for HPV vaccine were conducted earlier than in Korea, the safety, efficacy, and effectiveness of HPV vaccines have been reported. Therefore, it is considered that basic research including an analysis of the effectiveness of HPV vaccines for policy decisions related to the expanding the HPV vaccine coverage and introducing of new vaccine in the future.

A Review of HPV Prevalence Research

Human papillomavirus is known to be a major cause of cervical cancer. More than 190 HPV genotypes have been identified and classified into a high-risk group (18 genotypes) and a low-risk group (12 genotypes) depending on the risk of disease progression. This report investigated the results of domestic and overseas studies on HPV prevalence and genotype distribution; identified prevalence and genotype distribution in Korea and in the world; and described and presented the results obtained as part of an internal research project at the KNIH. Through systematic review and meta-analysis, the previous study shows that the prevalence of HPV was found to be 10.7% (worldwide) and 13.6% (Korea and China) in women with normal cytology, respectively. HPV-16, HPV-18, HPV-31, HPV-58, and HPV-52 were the five most prevalent genotypes in the world. By contrast, in East Asia, including Korea, HPV-16, HPV-18, HPV-58, HPV-52, and HPV-70 were the prevalent genotypes. In an intramural research project conducted by the KNIH, the prevalence of HPV was estimated to be about 36% according to a meta-analysis. This result provides the basic statistics of HPV infection in Korea.

Overview of the Efficacy of Human Papillomavirus Virus Vaccines

Human papillomavirus (HPV) infection is the main cause of cervical cancer and major viruses related to carcinogenesis in various malignant diseases such as cervical cancer, vaginal cancer, vulvar cancer, anal cancer, and head and neck cancer. Cervical cancer is the second most prevalent female cancer in the world and the fourth in Korea. Prophylactic HPV vaccines in widespread use include the used in South Korea to prevent cervical cancer are bivalent (2-valent HPV vaccine; Cervarix), quadrivalent (4-valent HPV vaccine; Gardasil), and nonavalent (9-valent HPV vaccine; Gardasil9). Since HPV vaccines the first approval in 2006, 115 countries have include HPV vaccines in their national immunization programs, that its preventive effect is as much as 70%, and that the incidence of high-risk types of HPV has gradually decreased. According to HPV cohort studies in Korea, about 26% of adult women have an HPV vaccination history and show a low incidence of HPV-16/18 genotypes compared to unvaccinated women. In the countries that National Immunization Programs for HPV vaccine were conducted earlier than in Korea, the safety, efficacy, and effectiveness of HPV vaccines have been reported. Therefore, it is considered that basic research including an analysis of the effectiveness of HPV vaccines for policy decisions related to the expanding the HPV vaccine coverage and introducing of new vaccine in the future.

A Review of HPV Prevalence Research

Human papillomavirus is known to be a major cause of cervical cancer. More than 190 HPV genotypes have been identified and classified into a high-risk group (18 genotypes) and a low-risk group (12 genotypes) depending on the risk of disease progression. This report investigated the results of domestic and overseas studies on HPV prevalence and genotype distribution; identified prevalence and genotype distribution in Korea and in the world; and described and presented the results obtained as part of an internal research project at the KNIH. Through systematic review and meta-analysis, the previous study shows that the prevalence of HPV was found to be 10.7% (worldwide) and 13.6% (Korea and China) in women with normal cytology, respectively. HPV-16, HPV-18, HPV-31, HPV-58, and HPV-52 were the five most prevalent genotypes in the world. By contrast, in East Asia, including Korea, HPV-16, HPV-18, HPV-58, HPV-52, and HPV-70 were the prevalent genotypes. In an intramural research project conducted by the KNIH, the prevalence of HPV was estimated to be about 36% according to a meta-analysis. This result provides the basic statistics of HPV infection in Korea.

Status of HPV vaccination among HPV-infected women aged 20–60 years with abnormal cervical cytology in South Korea: a multicenter, retrospective study / 부인종양

Objectives@#Since 2007, human papillomavirus (HPV) vaccines have been administered for the prevention of cervical cancer in Korea. We investigated the status of HPV vaccination among HPV-infected adult women with abnormal cervical cytology before the introduction of National Immunization Program. @*Methods@#From 2010 to 2016, HPV-positive women (age, 20–60 years) with atypical squamous cells of undetermined significance or low-grade squamous intraepithelial lesion (LSIL) were enrolled from five hospitals across Korea. Their HPV genotype, epidemiologic, and clinical data, including HPV vaccination history, were obtained. We compared the epidemiological characteristics and prevalence of HPV-16/18 genotypes between vaccinated and unvaccinated women. @*Results@#Among the 1,300 women, approximately 26% had a history of vaccination. Vaccinated patients were significantly younger, unmarried, and had a higher education level than unvaccinated women. For HPV-vaccinated individuals by vaccine dose, there was a significant younger age at vaccination initiation (p=0.025), longer duration from HPV vaccination to Pap test date (p=0.001), and lower proportion of HPV-16/18 (p=0.028) in the women with three doses. There was a significantly lower prevalence of HPV-16/18 genotypes in women who were vaccinated at least 12 months prior than in unvaccinated women(adjusted prevalence ratio [aPR]=0.51; 95% confidence interval [CI]=0.29–0.88). For women with LSIL, the prevalence of the HPV-16/18 genotypes was significantly lower in women who were vaccinated more than 12 months prior than in unvaccinated women (aPR=0.35; 95% CI=0.13–0.96). @*Conclusion@#This study highlighted the status of HPV vaccination and the prevalence of HPV-16/18 genotypes among HPV-infected women with abnormal cervical cytology according to HPV vaccination. It provides preliminary information regarding the status of HPV vaccination among Korean adult women.

Status of HPV vaccination among HPV-infected women aged 20–60 years with abnormal cervical cytology in South Korea: a multicenter, retrospective study / 부인종양

Risk of cervical dysplasia among human papillomavirus-infected women in Korea: a multicenter prospective study / 부인종양

OBJECTIVE: Human papillomavirus (HPV) infection is the most important risk factor for cervical cancer, which progresses from precursor lesions with no symptom if left untreated. We compared the risk of cervical dysplasia among HPV-positive Korean women based on HPV types and infection patterns. METHODS: We observed participants of a 5-year multicenter prospective cohort study, comprising HPV-positive women with either atypical squamous cells of undetermined significance or low-grade squamous intraepithelial lesion of the cervix at their enrollment. Follow-ups, comprising cytology and HPV DNA testing results, were included in the final analysis. Incidence was calculated for each infection pattern (persistent infection, incidental infection, and clearance). To investigate cervical dysplasia risk, we used Cox proportional hazard models adjusted for variables that were significantly different among infection patterns. From April 2010 to September 2017, 71 of 1,027 subjects developed cervical dysplasia more severe than high-grade squamous intraepithelial lesion of the cervix. RESULTS: Of these 71 subjects, persistent infection, incidental infection, and clearance were noted in 30, 39, and 2 individuals, respectively. Based on changes in DNA results during follow-up, cumulative incidence was 27.2%, 10.4%, and 0.5% for persistent infection, incidental infection, and clearance, respectively. Compared to clearance, the adjusted hazard ratios for cervical dysplasia were 51.6 and 24.1 for persistent and incidental infections, respectively (p < 0.001). CONCLUSION: Individuals persistently infected with the same HPV types during the follow-up period had the highest risk of severe cervical dysplasia. Hence, it is necessary to monitor HPV types and infection patterns to prevent severe cervical precancerous lesions.