OBJECTIVETo explore the neutralization capacities of different types of human serum to measles virus epidemic strains and vaccine strain.

METHODSNeutralization antibody (NT) to Shanghai 191 and measles virus isolates in 2005 were tested using acute and convalescent serum samples from diagnosed measles patients, children serum samples collected before and after vaccination and serum samples of migrant residents, from 3 different regions. Additionally, animal immune serum referring to vaccine strain and 3 epidemic strains were prepared and used to undergo crossing neutralization test with corresponding strains mentioned-above. Antigenic ratios were calculated.

RESULTSGMT value of NT of after-immune serum to vaccine strains was 50.82,1.86 times higher than that to MVi/ZJ/05/7 (GMT was 27.35), whereas GMT value of convalescent serum to MVi/ZJ/05/7 (GMT was 386.95) was obviously higher than that to vaccine strain (GMT was 1:151.83),and GMT value of migrant residents' serum in 3 regions to MVi/ZJ/05/7 were 2.22-4.17 times lower than that to vaccine strain. Meanwhile,the antigenic ratios between MVi/ZJ/ 99/1, MVi/ZJ/04/1, MVi/ZJ/05/7 and vaccine strain were found to be 4.28,5.24 and 5.66 respectively. Additionally,low NT titers to vaccine strain were found in patients' acute sera and GMT value was over 1:4.

CONCLUSIONThere were obvious differences on neutralization antibody of different types of serum to measles vaccine strain and epidemic strains which indicating the antigenic diversity of epidemic strains had influenced the protective effectiveness of vaccine antibody to epidemic strains. It was of significance to carry on research projects on the antigenic diversity and effectiveness of measles vaccine.

Animals ; Antibodies, Neutralizing ; blood ; immunology ; Antibodies, Viral ; blood ; immunology ; Antigens, Viral ; genetics ; immunology ; Child ; China ; epidemiology ; Humans ; Measles ; epidemiology ; immunology ; prevention & control ; Measles Vaccine ; immunology ; Measles virus ; genetics ; Neutralization Tests ; Vaccination

OBJECTIVES: This study describes a plan that was designed to prevent a measles outbreak that showed a changed outbreak pattern. This study is based on the epidemiological investigation of a measles outbreak in a preschool in Incheon, Korea, 2006. METHODS: The subjects were 152 students at a preschool where a measles outbreak occurred. A questionnaire survey was conducted and serological testing for measlesspecific IgM was preformed. RESULTS: Of the fifteen confirmed, identified cases, eleven patients had been vaccinated with one dose, one patient had received two doses and three patients were unvaccinated. The three unvaccinated cases consisted of one 5-year-old child, one 3-year-old child and one 16-month-old infant. For the cases with one dose of the vaccination, there were 11 cases, which consisted of six 5-year-old children, two 4-year-old children, two 3-year-old children and one 2-year-old child. The case with two doses of the vaccination was one 4-year-old child. The attack rate of measles was 100% in the 0-dose group, 11.2% in the 1-dose group and 2.0% in the 2-dose group. The vaccine's efficacy was 88.8% in the 1-dose group and 98.0% in the 2-dose group. The vaccine effectiveness for the 2-dose group was higher than that of the 1-dose group. CONCLUSIONS: High coverage with a 2-dose vaccination should be maintained, and the vaccination should be given at the suitable time to prevent a measles outbreak with a changed outbreak pattern.
Child, Preschool ; *Disease Outbreaks/prevention & control ; Humans ; Immunization Programs ; Korea ; Measles/*epidemiology/immunology/*prevention & control/virology ; Measles Vaccine/*administration & dosage ; Preventive Medicine ; Questionnaires

OBJECTIVETo analyze the measles immunity level of persistent population in Beijing.

METHODSA total of 2125 objects from 10 age groups, who had been living in Beijing for over 6 months, were selected from urban and rural areas in Beijing in 2012. Demographic characteristics, history of measles and vaccine immunization were investigated by questionnaire. 5 ml blood sample of each subject was collected, and the Measles IgG antibody was measured by ELISA assay.

RESULTSPositive rate of measles antibody was 84.71% (1800/2125) and standardized positive rate was 88.07% . Median of antibody was 960.46 IU/L. Positive rate and median of measles antibody were significantly different between population from different age groups (χ(2) = 341.60, P < 0.01; H = 216.27, P < 0.01). Antibody positive rate and median were lowest in the <1 year age group, which were separately 43.06% (90/209) and 185.80 IU/L; and highest in the 1-4 (97.31% (181/186) and 2448.81 IU/L) and 5-9 years age group (96.46% (218/226) and 1910.72 IU/L). The range of antibody positive rate and median in adults of ≥ 15 years were 81.98%-90.14% and 744.38-1474.84 IU/L. Antibody positive rate and median in persistent population, which were separately 82.45% (883/1071) and 899.82 IU/L, were lower than those in migrant population, which were 87.00% (917/1054) and 166.19 IU/L, respectively (χ(2) = 8.51, P < 0.01;U = 538 704.00, P < 0.01). Antibody positive rate and median in population with vaccination history, which were separately 91.95% (891/969) and 1443.11 IU/L, were higher than those population without vaccination history and people whose history unknown (32.95% (57/173) , 127.33 IU/L; 86.67% (852/983) , 923.73 IU/L). The difference showed statistical significance (χ(2) = 399.92, P < 0.01; H = 202.11, P < 0.01).

CONCLUSIONAmong the persistent population in China, measles antibody level among the children aging 1-9 years old was high enough to prevent outbreak and epidemic of measles. However, we should try our best to strengthen the measles antibody level among the babies younger than 1 year old and the migrant population aging between 15 and 40 years old.

Adolescent ; Adult ; Antibodies, Viral ; blood ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Humans ; Infant ; Male ; Measles ; epidemiology ; immunology ; prevention & control ; Measles virus ; Young Adult

OBJECTIVETo explore the distinction between wild-type strain MVi/Zhejiang, CHN/7.05/4 and vaccine strain Shanghai-191 at genome level.

METHODSAfter sequencing of measles wild-stain MVi/Zhejiang. CHN/7.05/4, the distinction between the wild-type strain and the vaccine strain was analysed by MEGA 3.1 software at genome level, and the antigen variation was studied by means of combining the epidemiological data.

RESULTSThere were 822 nucleotide differences (5.17%) and 161 amino acid differences between these two strains, including three glycosylation sites variation found. Meanwhile, the antigen ratio between wild-type strain and vaccine strain was found to be 5.66.

CONCLUSIONThere should be certain differences between the contemporary wild-type strain MVi/Zhejiang, CHN/7.05/4 and vaccine strain Shanghai-191 at genome level, and the protective effects of measles vaccine should be studied further.

Antigenic Variation ; China ; epidemiology ; Comparative Genomic Hybridization ; Genome, Viral ; Humans ; Measles ; epidemiology ; prevention & control ; virology ; Measles Vaccine ; genetics ; Measles virus ; classification ; genetics ; immunology ; Sequence Analysis, Protein ; Sequence Analysis, RNA