Humans ; Mass Vaccination ; COVID-19 Vaccines/therapeutic use* ; COVID-19/prevention & control* ; Immunity, Herd ; Vaccination

Early Detection of Cancer ; Female ; Humans ; Mass Screening ; Papillomavirus Infections/prevention & control* ; Papillomavirus Vaccines/therapeutic use* ; Uterine Cervical Neoplasms/prevention & control* ; Vaccination

OBJECTIVES: This study aimed to extend an epidemiological model (SEIHFR) to analyze epidemic trends, and evaluate intervention efficacy. METHODS: SEIHFR was modified to examine disease transmission dynamics after vaccination for the Ebola outbreak. Using existing data from Liberia, sensitivity analysis of various epidemic scenarios was used to inform the model structure, estimate the basic reproduction number ℜ₀ and investigate how the vaccination could effectively change the course of the epidemic. RESULTS: If a randomized mass vaccination strategy was adopted, vaccines would be administered prophylactically or as early as possible (depending on the availability of vaccines). An effective vaccination rate threshold for Liberia was estimated as 48.74% among susceptible individuals. If a ring vaccination strategy was adopted to control the spread of the Ebola virus, vaccines would be given to reduce the transmission rate improving the tracing rate of the contact persons of an infected individual. CONCLUSION: The extended SEIHFR model predicted the total number of infected cases, number of deaths, number of recoveries, and duration of outbreaks among others with different levels of interventions such as vaccination rate. This model may be used to better understand the spread of Ebola and develop strategies that may achieve a disease-free state.
Africa, Western ; Basic Reproduction Number ; Disease Outbreaks ; Ebolavirus ; Humans ; Liberia ; Mass Vaccination ; Vaccination ; Vaccines

The 2018 National Guideline for Tuberculosis Control, which was published by the Korea Centers for Diseases Prevention and Control (KCDC), mandates conducting an epidemiological survey among close contacts of active tuberculosis patients at public institutions such as schools. In the procedure for these surveys, the tuberculin skin test (TST) is mandated as the screening test for latent tuberculosis infection in elementary school students. However, several guidelines recommend using the interferon-gamma releasing assay (IGRA) for contacts aged over 5 years with a Bacillus Calmette–Guérin vaccination history. The main reason for this is that IGRA has a higher specificity and lower false positive rate than TST. In addition, IGRA requires only a single visit to draw blood and the results are available within 24 hours. These advantages could promote cooperation from both parents and students in conducting these surveys. Thus, these findings regarding the benefits of IGRA for surveys of close contacts at elementary schools should be incorporated into the KCDC guideline.
Bacillus ; Humans ; Interferon-gamma ; Interferon-gamma Release Tests ; Korea ; Latent Tuberculosis ; Mass Screening ; Mycobacterium tuberculosis ; Parents ; Sensitivity and Specificity ; Skin Tests ; Tuberculin ; Tuberculin Test ; Tuberculosis ; Vaccination

BACKGROUND: The seropositivity rate of hepatitis B surface antigen (anti-HBs) antibodies is known to be ≥95% after hepatitis B virus vaccination during infancy. However, a low level or absence of anti-HBs in healthy children is discovered in many cases. Recent studies in adults reported that a reduced anti-HBs production rate is related to obesity.PURPOSE: To investigate whether body mass index (BMI) affects anti-HBs levels in healthy children following 3 serial dose vaccinations in infancy.METHODS: We recruited 1,200 healthy volunteers aged 3, 5, 7, or 10 years from 4-day care centers and 4 elementary schools. All subjects completed a questionnaire including body weight, height, and vaccine type received. Levels of serum hepatitis B surface antigen (HBsAg) and anti-HBs in all subjects were analyzed using electrochemiluminescence immunoassay. The standardized scores (z score) for each sex and age were obtained using the lambda-mu-sigma method in the 2017 Korean National Growth Charts for children and adolescents.RESULTS: Our subjects (n=1,200) comprised 750 males (62.5%) and 450 females (37.5%). The overall anti-HBs seropositivity rate was 57.9% (695 of 1,200). We identified significant differences in mean BMI values between seronegative and seropositive groups (17.45 vs. 16.62, respectively; P<0.001). The anti-HBs titer was significantly decreased as the BMI z score increased adjusting for age and sex (B=-15.725; standard error=5.494; P=0.004). The probability of anti-HBs seropositivity based on BMI z score was decreased to an OR of 0.820 after the control for confounding variables (95% confidence interval, 0.728–0.923; P=0.001).CONCLUSION: There was a significant association between anti-HBs titer and BMI z score after adjustment for age and sex. Our results indicate that BMI is a potential factor affecting anti-HBs titer in healthy children.
Adolescent ; Adult ; Antibodies ; Body Mass Index ; Body Weight ; Child ; Confounding Factors (Epidemiology) ; Female ; Growth Charts ; Healthy Volunteers ; Hepatitis B Surface Antigens ; Hepatitis B virus ; Hepatitis B ; Hepatitis ; Humans ; Immunoassay ; Male ; Methods ; Obesity ; Vaccination

PURPOSE: Annual influenza vaccination is the best strategy to prevent healthcare-associated influenza transmission. Influenza vaccination rates among healthcare workers (HCWs) vary by country, region, and year. We investigated the influenza vaccination rates for HCWs during the 2017–2018 influenza season in South Korea, where a non-mandatory vaccination campaign was conducted.METHODS: We retrospectively investigated factors affecting the influenza vaccination rate among HCWs during the 2017–2018 influenza season in three tertiary hospitals in Goyang City, where the non-mandatory influenza vaccination program is conducted.RESULTS: Consequently, 6,994 of 7,180 HCWs (97%) were included, and the overall vaccination rate was 85%. Nurses had the highest rate with 92%, followed by health technicians (88%), physicians (84%), and non-medical HCWs (79%, P<0.001). Vaccination rates differed, depending on the frequency of contact with patients in the non-medical HCWs (frequent contact vs. less-frequent contact; 90% vs. 73%, P<0.001).CONCLUSIONS: The influenza vaccination rate among HCWs during the 2017–2018 influenza season in Korea was 85%, which is among the highest rates compared with previously reported non-mandatory vaccination rates in other countries. The vaccination rate may vary depending on the HCW's occupational characteristics, including the extent of contact with the patient. Therefore, a multifaceted strategy is needed to increase the vaccination rate of HCWs.
Delivery of Health Care ; Humans ; Infectious Disease Transmission, Professional-to-Patient ; Influenza Vaccines ; Influenza, Human ; Korea ; Mass Vaccination ; Retrospective Studies ; Seasons ; Tertiary Care Centers ; Vaccination

BACKGROUND: The purpose of this study was to provide health screening for low-income people and early diagnosis and treatment for health risk factors and diseases for the promotion of the health of vulnerable people. This study was also aimed toward the implementation of a comprehensive cancer health screening system to improve quality of life.METHODS: This study was conducted in 1,546 subjects aged >40 years who underwent free cancer screening between February and December 2017 in the Jeollanam-do region. In the first, we performed a survey HBsAg, Anti-HBs, 54 peoples with hepatitis B abnormalities were checked to secondary screening, HBeAg/Anti-HBe, HBV DNA.RESULTS: The overall HBsAb total seropositivity rate was 59.8% (924/1,546), and the HBsAb total seronegativity rate was 40.2% (622/1,546). The HBsAg total seropositivity rate was 3.8% (58/1,546) overall, 1.7% (26/1,546) in the men, and 2.1% (32/1,546) in the women. The HBeAg seropositivity rate was 11.1% (6/54) in the second hepatitis B screening.CONCLUSION: We found that the positivity and negativity rates of HBsAb (Anti-HBs) were similar to those reported in other studies, but the positivity rate of HBeAg was slightly higher in the second hepatitis screening. In future surveys, factors must be analyzed, including an additional investigation of the related health risk factors to confirm the factors that affect diagnosis and initial evaluation results.
Antigens, Surface ; Diagnosis ; DNA ; Early Detection of Cancer ; Early Diagnosis ; Female ; Hepatitis B e Antigens ; Hepatitis B Surface Antigens ; Hepatitis B virus ; Hepatitis B ; Hepatitis ; Humans ; Jeollanam-do ; Male ; Mass Screening ; Quality of Life ; Risk Factors ; Seroepidemiologic Studies ; Vaccination

Outbreaks of porcine reproductive and respiratory syndrome virus (PRRSV) in vaccinated sow herds from occurrence to stabilization were monitored and analyzed in terms of serology and reproductive performance. Three different conventional pig farms experienced severe reproductive failures with the introduction of a type 1 PRRSV. These farms had adopted mass vaccination of sows using a type 2 PRRSV modified live vaccine (MLV). Therefore, to control the type 1 PRRSV, an alternative vaccination program utilizing both type 1 and type 2 MLV was undertaken. Following whole herd vaccinations with both types of MLV, successful stabilization of PRRS outbreaks was identified based on serological data (no viremia and downward trends in ELISA antibody titers in both sows and suckling piglets) and recovery of reproductive performance. Additionally, through comparison of the reproductive parameters between outbreak and non-outbreak periods, it was identified that PRRSV significantly affected the farrowing rate and the number of suckling piglets per litter at all three pig farms. Comparison of reproductive parameters between periods when the different vaccination strategies were applied revealed that the number of piglets born in total and born dead per litter were significantly increased after the introduction of the type 1 PRRS MLV.
Agriculture ; Disease Outbreaks ; Enzyme-Linked Immunosorbent Assay ; Immunity, Herd ; Immunity, Heterologous ; Mass Vaccination ; Porcine Reproductive and Respiratory Syndrome ; Porcine respiratory and reproductive syndrome virus ; Vaccination ; Viremia

OBJECTIVE: Knowledge regarding the prevalence and distribution of human papillomavirus (HPV) genotyping in healthy women is important in establishing strategies for cervical cancer screening and HPV vaccination. METHODS: A total of 18,170 women who visited a Korean Medical Institute for health check-ups were recruited retrospectively; they underwent HPV genotyping and conventional cervical cytology. An HPV DNA test was performed using the Anyplex™ II HPV 28 detection system (Seegene) or HPV Liquid Bead Microarray (Osang Healthcare). The distribution of HPV genotypes was assessed according to cervical cytology and age. RESULTS: HPV was detected in 3,037 (16.71%) of the 18,170 women enrolled, and 2,268 (12.48%) were positive for high-risk (HR) HPV. In total, HPV 53 (9.69% of all detected HPV viruses) was the most common type; HPV 58 (7.90%) and 52 (7.81%) were also common. HPV 54 (6.99%) was common in low-risk subjects. Overall and in the normal cytology group, the most common HPV genotype was HPV 53, whereas HPV 58 was more common in women who had atypical squamous cells of undetermined significance or low-grade squamous intraepithelial neoplasia cervical cytology. In addition, HPV 16 was the most common type in cases with high-grade squamous intraepithelial neoplasia (HSIL)/atypical squamous cells-cannot exclude HSIL. Among women with normal cytology, 76 of 231 (32.9%) women under 24 years of age were positive for HR HPV, whereas 84 of 852 (9.9%) women aged 55–59 years were positive. CONCLUSION: HPV 53 was the most prevalent genotype in healthy women. Distribution of HPV genotypes varied with cervical cytology and age. Our study provides important baseline data for the recently implemented national HPV vaccination program.
Atypical Squamous Cells of the Cervix ; Cervical Intraepithelial Neoplasia ; Female ; Genotype ; Human papillomavirus 16 ; Human Papillomavirus DNA Tests ; Humans ; Mass Screening ; Papanicolaou Test ; Papillomaviridae ; Prevalence ; Republic of Korea ; Retrospective Studies ; Uterine Cervical Neoplasms ; Vaccination

Eradication of cervical cancer involves the expansion of human papillomavirus (HPV) vaccine coverage and the development of efficient screening guidelines that take vaccination into account. In Korea, the HPV National Immunization Program was launched in 2016 and is expected to shift the prevalence of HPV genotypes in the country, among other effects. The experiences of another countries that implement national immunization programs should be applied to Korea. If HPV vaccines spread nationwide with broader coverage, after a few decades, cervical intraepithelial lesions or invasive cancer should become a rare disease, leading to a predictable decrease in the positive predictive value of cervical screening cytology. HPV testing is the primary screening tool for cervical cancer and has replaced traditional cytology-based guidelines. The current screening strategy in Korea does not differentiate women who have received complete vaccination from those who are unvaccinated. However, in the post-vaccination era, newly revised policies will be needed. We also discuss on how to increase the vaccination rate in adolescence.
Adolescent ; Early Detection of Cancer ; Female ; Genotype ; Humans ; Immunization Programs ; Korea ; Mass Screening* ; Papillomavirus Vaccines ; Prevalence ; Rare Diseases ; Uterine Cervical Neoplasms* ; Vaccination*