• Journal of Veterinary Clinics
• /
• v.23 no.3
• /
• pp.308-313
• /
• 2006

This study was performed to monitor the level of serum canine parvovirus(CPV) antibody titers in adult dogs throughout the Korea from January 2003 to April 2004. A total of clinically healthy 885 dogs between 1 year and 17 years old were included in this study. Serum antibody titers against CPV were measured by means of hemagglutination inhibition(HI) titers at the time dogs were brought to the hospital for revaccination. Most of dogs had been primarily vaccinated or previously revaccinated. Dogs were grouped by age, breed, sex, and primary vaccination and revaccination to determine whether these factors were associated with antibody titers. Serum CPV titers ${\geq}80$ were considered protective. Protective antibodies against CPV were present in 95.0% of the population. Breed, age, and primary vaccination and revaccination were not significantly associated with serum CPV antibody titers. But sex was significantly associated with CPV antibody titers. The results of this study have shown that there is a need to reconsider the annual revaccination strategy against CPV infection.

• Clinical and Experimental Pediatrics
• /
• v.51 no.11
• /
• pp.1165-1171
• /
• 2008

Purpose : This study aimed to identify the true extent of non-responsiveness in full-term infants born from HBsAg-negative or HBsAg-positive mothers and vaccinated against hepatitis B virus (HBV) at 0, 1, and 6 months of age and to evaluate the effect of revaccination among non-responders. Methods : The study included 716 full-term infants born in 2004-2007. Of 716, 662 infants (A group) were born to HBsAg-negative mothers and 54 infants (B group: 50, except HBsAg-positive infants) were born to HBsAg-positive mothers. All infants were administered DNA recombinant vaccines at 0, 1, and 6 months of age. B group infants received hepatitis B immunoglobulin at birth. Anti-HBs titers were tested at 7-12 and 9-15 months in A and B groups, respectively. Three revaccination doses were administered to non-responders whose anti-HBs titers were under 10 mIU/ml; revaccinated infants were retested at 1-3 months after last vaccination. The association between HBeAg seropositivity of mother and the failure of HBV immunoprophylaxis was evaluated. Results : The seroconversion rates after primary hepatitis B vaccination were higher in A group (94.1%) than in B group (78%, P<0.001). The seroconversion rates were high in revaccinated infants (A group non-responders: 96.9%, B group non-responders: 87.5%). The failure of HBV immunoprophylaxis was significantly associated with maternal HBeAg seropositivity (P<0.001). Conclusion : The seroconversion rates after primary hepatitis B vaccination were low in B group infants. Revaccination of non-responders in B group was very effective. Therefore, anti-HBs testing and revaccination of B group is very important. Revaccination of non-responders in A group was also very effective. Thus, testing the immune status of infants born to HBsAg-negative mothers even after primary hepatitis B vaccination should be considered. However, to realize this, further studies on the cost-effectiveness of anti-HBs testing in healthy full-term infants are necessary.

• Pediatric Infection and Vaccine
• /
• v.4 no.1
• /
• pp.133-139
• /
• 1997

Purpose : To determine the age-specific seropositivity and the level of measles specific IgG in vaccinated adolescents, the measles specific IgG titers were measured from the sera of junior & senior high school students in Seoul, Korea. Methods : From May to July in 1996, 216 sera were collected from junior & senior high school students(male : 110, female : 106) aged 12 to 17 years who were vaccinated and had no history of natural measles. Measles specific IgG titers were measured using ELISA method($SIA^{TM}$ Measles IgG Kit, Sigma Co. St. Louis, Mo). Results : The seropositivity of measles specific IgG in vaccinated adolescents aged 12 to 17 years was 91.2%. There were no significant correlations between age and seropositivity as well as between age and measles specific IgG level. Conclusions : We consider that our data suggest the necessity of revaccination of measles in adolescents. Further considerations should be required to establish an appropriate revaccination method and to evaluate the efficacy of revaccination of previously vaccinated adolescents.

• Pediatric Infection and Vaccine
• /
• v.9 no.1
• /
• pp.67-73
• /
• 2002

Purpose : Despite of the appropriate measles vaccination programs, epidemics occur every 2~3 years and especially occurred in large group in late of 2000 and early of 2001. To evaluate the effect of the vaccination, needs for revaccination and to determine the optimal age for revaccination, we examined measles specific IgG and IgM in mealses patients and investigated different antibody appearance according to vaccination history. Methods : Anti-measles antibodies were checked in sera of 201 patients(male : 117, female : 84) that are responsible for Criteria for Disease Control among 298 patients that are suspicious of measles including inpatients and outpatients in Wonju Christian Hospital from June in 2000 to June in 2001. They were checked by immunofluorescent assay. Then we classified them according to sex, month, distribution of age due to vaccination and appearance of measles antibody. Results : The ratio of male and female was 1.4 : 1. The maximum incidence was 38 cases(18.9%) in May in 2001. Incidence was increased from November in 2000 to January in 2001 and decreased in February and March in 2001. Thereafter it was increased from April in 2001 again and decreased from June. There were 93 cases(46.3%) in vaccinated group and 108 cases(53.7%) in unvaccinated group. In the distribution according to age in vaccinated group, there were 54 cases(58.1%) in more than 10 years old, 15 cases(16.0%) between 7 and 10 years old, 12 cases(12.9%) between 15 months and 3 years old, 6 cases (6.5%) between 4 and 6 years old and 6 cases(6.5%) between 6 months and 14 months old. In the distribution according to age in unvaccinated group, there were 88 cases(81.5%) between 6 months and 14 months old, 9 cases(8.3%) between 15 months and 3 years old, 7 cases(6.5%) less than 6 months old, 3 cases(2.8%) more than 10 years old and 1 case(0.9%) between 7 and 10 years old. In the distribution of measles specific IgG and IgM, 78 cas (87.6%) were IgG(+), IgM(+) and 11 cases(12.4%) are IgG(+), IgM(-) in vaccinated group. In unvaccinated group, there were 69 cases(63.9%) of IgG(+), IgM(+) and 39 cases (36.1%) of IgG(-), IgM(+). Con c lu s i on s : We thought that measles incidence was peaked between 6 months and 14 months old in unvaccinated group because of maximum decrement of transplacental matenal antibody and was peaked in more than 10 years old in vaccinated group because of maximum decrement of measles specific IgG. We think that measles revaccination as well as vaccination and especially optimal age for revaccination is very important to prevent measles successfully.

• Pediatric Infection and Vaccine
• /
• v.3 no.2
• /
• pp.185-193
• /
• 1996

Purpose : The incidence of measles was gradually decreased since 1963 when measles vaccination was firstly developed and liscenced in the world. But, recently the outbreaks of measles in infants and school children have been reported despite of wide spread use of measles vaccination. This study was performed to evaluate the efficacy of measles vaccination and the necessity of revaccination in Korean infants and children. Methods : 168 subjects of mothers and neonates, infants and children were enrolled in this study during the periods of 10 months from March to December in 1995. Measles specific IgG in the sera of mothers and children was measured using EIA kit (Sigma Co., MO, USA). Antibody titer of over or equal to 110 AU/ml was considered positive. Results : The results obtained were as follows. 1) Values of measles specific IgG in the sera of mother and neonate were 82.9 AU/ml and 89.3 AU/ml respectively and were rapidly decreased within 6 month after birth. Positive antibody levels (${\geq}$ 110 AU/ml) were observed in only 25 % of neonates. 2) In vaccinated children, values of measles specific IgG were 117.4 AU/ml in 9~15 month group, 76.9 AU/ml in 3~6 year group and 79.5 AU/ml in 10~15 year group after either one or two times of measles vaccination. Positive antibody levels in vaccinated children were observed in 57.7% of 9~15 month group, 38.4% of 3~6 year group and 34.7% of 10~15 year group. Conclusion : These results suggest that primary measles vaccination before 6 months of age can be considered and revaccination of measles should be recommended before 3~6 years of age. Further studies will be needed to clarify the reasons of high proportion of primary measles vaccination failure and to established the appropriate schedule of measles vaccination in korean infants and children.

• Journal of Veterinary Clinics
• /
• v.26 no.5
• /
• pp.423-428
• /
• 2009

There were outbreaks of canine distemper in Korea from the late 1990's to the early 2000's even though modified live CDV vaccines had been used as the same way as before. The present study was undertaken to investigate the levels of neutralizing antibodies in the Korean dog population, and the factors associated with the levels, with special reference to the vaccination history of the dogs. A total of 772 serum samples were from clinically healthy dogs with over one year old throughout the Korea from January 2003 to April 2004. Details on the sex, breed, age, vaccination status and disease histories were recorded. The level of neutralizing antibodies titer was determined with a modified version of the microneutralization test. Titers over 16 were classified as protective CDV antibody titers. The overall rate of adult dogs with protective antibody titers was 96.0%. The dogs with protective antibody titers varied depending on age, sex, rearing environment and vaccination status. Because the majority of healthy adult dogs in Korea had adequate serum antibody titers against CDV and the immunity provided by the vaccinations is claimed to last for several years, annual revaccination protocol for CDV in adult dogs should be reconsidered.

• Pediatric Infection and Vaccine
• /
• v.4 no.1
• /
• pp.126-132
• /
• 1997

Measles outbreak in the world was decreased since measles vaccine had been introduced. Although vaccination rate is high, measles was not eradicated and measles reappeared among vaccinated children. We measured measles-specific antibody from the vaccinated and unvaccinated groups who had experienced apparent measles in the Seongnam city in 1993. The results were as follows. 1) The data included total 126 children (M:F=1 : 1). Age distribution of measles outbreak revealed 6 children in 5yr, 11 in 6yr, 20 in 7yr, 39 in 8yr, 22 in 9yr, 11 in 10yr, 11 in 11yr, and 6 in 12yr. 2) MMR vaccination rate was 78.6%(99/126) in the children who had experienced measles. Positive rate of measles-specific IgM Ab was 80.8% (80/99) among the vaccinated group and among 9E.6.% (25/27) the unvaccinated. 3) Positive rate of measles-specific IgG Ab was 90.9% (90/99) among MMR-vaccinated group, and 85.2% (23/27) in unvaccinated group. In conclusion, measles-specific IgM antibody have been detected more than 1 month in most patients. The relatively high proportion of measles-specific IgM positivity may mean primary vaccine failure. To booster the antibody titers and to prevent measles epidemic in school-aged children, revaccination of measles should be considered.

• Clinical and Experimental Pediatrics
• /
• v.49 no.8
• /
• pp.857-863
• /
• 2006

Purpose : To evaluate the immunogenicity of hepatitis B vaccine among very low birth weight infants(VLBWI) who were vaccinated at 0, 1, 6 months of chronological age and to determine the factors associated with antibody formations. Methods : A total of 243 VLBWI admitted to Seoul and Gangneung Asan Medical Center neonatal intensive care units from 1997 to 2004 were included. Of 243, 13 infants were born to HBs Ag positive mother. All infants were given DNA recombinant vaccine at 0, 1, and 6 months of chronological age. Infants born to HBs Ag positive mothers received hepatitis B immunoglobulin at birth and a total of 4 doses of vaccinations. An antibody level over 10 mIU/mL, tested at 3-4 months after last vaccination, was regarded as a positive seroconversion. Results : The seroconversion rates were 84.4 percent and 84.5 percent for VLBWI and extremely low birth weight infants(ELBWI), respectively. Of 28 seronegative infants who were given revaccinations, 60.7 percent seroconverted, resulting in 95.3 percent, 97.5 percent seroconversion rates for VLBWI and ELBWI, respectively. 76.9 percent of infants born to HBsAg positive mothers seroconverted and none became hepatitis B carriers. Factors such as gestational age, sex, various neonatal illness, and kinds of vaccinations did not influence the formation of the hepatits B antibody, however, the higher the weight at time of first vacciation yielded better seroconversion rate. Conclusion : Revaccination of seronegative VLBWI after 3 doses of hepatitis B vaccinaton is very effective. Therefore, testing the immune status after the hepatitis B vaccination, a practice not routinely done, is highly recommended.

• Clinical and Experimental Pediatrics
• /
• v.45 no.8
• /
• pp.980-986
• /
• 2002

Purpose : Although the number of patients with measles have dramatically decreased since the introduction of measles vaccines in 1965, measles outbreaks have occurred periodically every 4-6 years during the 1990s(1989-1990 and 1993-1994). During 2000-2001, measles prevailed all over the country again. A characteristic of current epidemics is that the majority of affected population was infants and school-aged children. This study was designed to analyze the epidemic and clinical features of measles prevalence during 2000-2001 and to find ways to overcome vaccination failure. Methods : We reviewed the records of 59 patients with mealses admitted in the Pediatric Department of Pusan National University Hospital from January 2000 to October 2001 for patient's age, month of admission, history of vaccination, clinical features and complications. Antibody titers of measles-specific IgM and IgG were measured by enzyme immunoassay. Results : The epidemic show two peaks in the age distribution. Forty three patients(72.9%) were under 2-years of age and 14 patients(23.7%) were over 5-years of age. Outbreaks had high incidence in July to August, 2000 and March to April, 2001, then faded away after July, 2001. Vaccinated group comprised 30.5% and unvaccinated group comprised 69.5% and their mean age was $9.25{\pm}4.27$ years old and $0.95{\pm}0.30$ years old respectively. Positive rate of IgM was 86.7% in vaccinated group and 90.3% in unvaccinated group. This means there was primary vaccine failure; 13 cases of 15 vaccinated patients were positive in IgM antibody. During the prevalence, two patients died with mealses complication. One of them was immunocompromised. Conclusion : To prevent another prevalence of measles in the future, we must enhance revaccination at ages 4-6 and check vaccination status when children enter elementary school. These will produce over 95% of herd immunity, with catch-up MMR vaccination which has been completed already.

• Journal of Preventive Medicine and Public Health
• /
• v.27 no.2 s.46
• /
• pp.337-365
• /
• 1994

Rubella is a viral disease with mild constitutional symptoms and generalized rashes. In childhood, it is an inconsequential illness, but when it occurs during early pregnant period, there are significant risks of heart defects, cataract, mental retardation to the fetus. The series of congenital defects induced by rubella is called 'congenital rubella syndrome'. Many research have been performed to find out more effective prevention program on rubella. The objectives of this study are, first, to calculate the incidence rate of acute rubella infection and congenital rubella syndrome in Korea, second, to evaluate economic efficiency of several rubella vaccination policies and to offer data for the most reasonable decision on vaccination policy. Study populations are 663,312 children of one year-old in 1992. The author has performed cost-benefit analyses according to the three vaccination policies-U.S.A.'s. U.K.'s and Sweden's. In this Study, the author got the incidence rate of acute rubella infection using the catalytic model. In the meantime, the author used 50 per 100,000 live births as the incidence rate of congenital rubella syndrome. The discount rate used in this study was 5 percent per annum. The sensitivity analyses were done with different discount rates (4%, 7%) and different incidence rate of congenital rubella syndrome (10,100 per 100,000 live births) : The study results are as follows: 1. Without vaccination, lifetime expenditures per patient for acute rubella infeciton amount to 14,822 won and the total expenditures to about 3.1 billion won. Meanwhile, lifetime expenditures per patient for congenital rubella syndrome amount to about 91 million won and the total expenditures to about 16.3 billion won without vaccination. 2. The cost of vaccination for a child of one year old was 2,322 won and the total cost for the one year old children was about 1.5 billion won (American style). The cost for vaccination of female children at fifteen was about 339 million won (Birtish style). And the cost of vaccination at one for both sex and female children at fifteen was about 1.9 billion won (Swedish style). 3. The benefit to cost ratios of vaccination of female children at fifteen that is the british mode of rubella vaccination, was 60.0 at the level of 80% population coverage and 48.6 at 100% coverage. It shows much higher benefit to cost ratio than those of the other two vaccination policies. 4. Both net benefits of vaccination at one (American style) and that of vaccinations at one and fifteen (Swedish style) range from about 17.0 billion to 17.8 billion won, those were larger than that of vaccinations of female children at fifteen (Birtish style, about 16.0 billion). 5. In marginal cost-benefit analysis of only additional program of revaccination, the benefit to cost ratios were 3.6 (80% coverage rate) or 0.6 (100% coverage rate). It implies that additional program was less efficient or inefficient. 6. In sensitivity analysis with different discount rates(4% or 7%) and different incidence rates of congenital rubella syndrome (10 or 100 per 100,000 live births), the benefit to cost ratios has fluctuated in wide range. However, all the ratios of vaccination of female children at fifteen were higher than those of the others. Even under the most conservative assumption, the benefit to cost ratios of all the rubella vaccination policies were higher than 3.3. In conclusion, all the rubella vaccination policies found to be cost-effective and particularly the vaccination of female children at fifteen was strongly recommended.