| [BACKGROUND]Measles is caused by the measles virus by a fever, respiratory tract catarrh symptom and systemic maculopapule of acute respiratory infectious diseases, characterized by disease after lasting immunity. Is the statutory c class infectious diseases in China.Early’60s live attenuated measles in China, with the development of the expanded programme on immunization, the measles epidemic basically under control. But in recent years, as a result of measles virus gene mutation, and lead to the incidence of measles rebounded, and age distribution has changed. As to speed up the reform and opening up, economic development, population flow increase at the same time, some children against measles leakage or immune failure, coupled with early after free with age gradually reduce immunity, causing minor epidemic measles. Measles virus is single strand RNA virus negative chain, now found eight genome (A-H)23genotypes (A, B1, Cl-2, D1-10, E, F, G1-3, H1-2), with six structure six major structural protein gene encoding. Where N gene C at the end of456bp sequence for the biggest gene variation degree, WHO is at least for the identification of genes required for gender sequence.From1993to2012in our country is divided into2756strains of measles virus isolates, found six genotypes, including H1for absolute advantage epidemic strains, namely the native plants of our country. Xu Wenbo according to the classification gene subtype of2%gene variants, such as the China’s advantage in H1genotype strains are divided into three subtypes:H1a, H1b, H1c. H1a subtype viruses are the main virus subtype, Chinese popular accounts for Hlb2nd, Hlc strain of the virus epidemic from1993-1994strong to weak in1995～2012.At present, the measles virus gene mutation, the current vaccine prevention is becoming a hot spot of research at home and abroad and the problem of adult measles, WHO asked to eliminate measles as a polio-free areas the next target, the monitoring and study of measles virus has become more urgent. Jinan measles virus, therefore, need to continue to strengthen to carry out the monitoring work. Before2013, confined to jinan to measles virus serological surveillance and immunization level monitoring, the genotyping of native measles epidemic strains and less paper work to antigenic drift, the need from molecular epidemiology research its effect on the spread of measles virus and popular, clarify the zhuhai measles antigenic variation characteristics of wild strains. This paper from the gene variants, epidemic, antibody level these three points to research, provide strong scientific basis for accelerating measles control in our country.[OBJECTIVES]1. Understanding of jinan in2013measles virus genotype and mutation characteristics of wild strains.2.2013jinan distribution between the three characteristics of measles virus, analysis the popular trend of measles virus.3. Understand the measles virus antibody levels in healthy people, provide scientific basis for the prevention and control of measles.[METHODS]A. Wild strain of measles gene variation characteristics of the research methods 1. The acquisition of jinan in2013suspected measles patients with pharyngeal swab and urine specimens, identification with fluorescent polymerase chain reaction (PCR), for measles virus samples, use the Vero-Slam cell separation.2. The extraction of RNA virus broth, with one step rt-pcr method for augmentation of measles virus nucleoprotein coding (nucleoprotein) N gene C at the end of456bp nucleotide fragments, amplification products directly used after sequencing DNAstar software will sequencing results with the international standard of the comparison and analysis of bioinformatics.3. Use the MEGA software will sequencing results and at the same time domestic and foreign sequence of wild strain results build wild strains of measles genetic evolutionary tree, analysis of genetic relationship. Second. Measles epidemic trend of the research methods1. According to the2009edition of the national measles surveillance program instructions in a timely manner to the information submitted to the Chinese center for disease control and prevention of measles cases disease surveillance information system and the results recorded.2. Will come from the Chinese center for disease control and prevention information system for disease control and prevention of infectious diseases report information management system, summarized the information of measles cases.3. Use Excel data analysis was carried out on the epidemic situation data, use the Epi-Info software rendering the geographical distribution of cases,The use of SPSS software for data for statistical analysis. Understanding of jinan in2013measles cases in time and region, population distribution between the "three", grasp the outbreak epidemic situation of measles virus in jinan and the change trend.4. To summarize immunization history of measles cases analysis.5. The clinical symptoms of measles cases data for statistical analysis. Third. Measles virus antibody level in healthy population analysis method 1. Using enzyme-linked immune method of measles antibody in the serum of healthy people (IgG) level, discusses different regions, different groups of live attenuated measles protective effect of epidemic strains.2. Using enzyme-linked immune method of school-age children immune level of measles antibody (IgG) in the serum before and after the test, analysis of immune success rate.3. The use of SPSS software for data for statistical analysis.[RESULTS]A. Wild strain of measles genetic variation characteristics research results1. The acquisition of jinan area of measles in2013suspected cases of specimens, a total of151,91, including swabs urine specimens from60, get the positive pharyngeal swab samples by fluorescence PCR detection of30, positive rate was33.33%, positive urine specimen in4, the positive rate is6.67%.30measles virus positive pharyngeal swab to19measles virus strain was isolated,4a urine specimen to2measles virus strain was isolated.21positive strains of pharyngeal swab specimens and urine specimens were from different cases, no coincidence.2.21strains of measles wild strains by the end of the N gene C456bp homology analysis of rt-pcr confirmed are Hla genotype, which found no vaccine related strains (A genotype), showed that the Hla subtypes of jinan advantage in2013. To measles virus Hla standard strains (china93-2) corresponding to the amino acid sequence is derived from the nucleotide sequence of nucleotides and standard,21specimens of gene mutations in9of456nucleotides are synonymous mutations. The genetic distance of0-0.017.3. The genetic evolutionary tree available from21strains of measles virus gene was isolated and domestic and foreign Hla strains in the same branch, explain the global epidemic situation is consistent, there are two small branch hint there may be two different small gene variants chain at the same time. Second.The research results of measles epidemic situation1. The incidence of jinan city in2013to4.46/10(299/6704036), clear spring, HuaiYin District, flyover, the onset of licheng district as the top three areas.2. Measles virus mainly affects children under the age of1, among them, the0-7months accounted for64%(105/164). Followed by adults over the age of20. The gender differences between different age groups has no statistical significance.3. The incidence of cases have immunization record crowds for10cases, accounting for3.3%of the total number of incidence, other are unknown. The0～1for6cases, at the age of1～5years old in3cases,1case was over the age of20.4. The distribution of clinical symptoms besides fever, rash, four for a cough, its symptoms, conjunctivitis and his spot, can be used for reference in the clinical.Third. Measles virus antibody level in healthy population1. The acquisition of295healthy people in serum, IgG positive rate was90.51%(267/295), GMC,1901.25(IU/ml). Positive rate and level of GMC some reports are basically identical with other domestic regions. In the three regions, in different parts of the antibody positive rate difference was statistically significant, shanghe the highest positive rate and GMC. There was no statistically significant difference of measles antibody positive rate between different gender. Measles antibody positive rate difference was statistically significant in all age groups, the highest rate of positive of2～4years old age group and GMC, GMC standards as the growth of the age roughly a downward trend.2. Babies under2.45cases of8months before and after the measles antibody levels to monitor, display before the immune antibody positive rate of33.33%, after the immune IgG antibody positive rate was100%, the level of GMC also increased from801.15IU/ml to2862.32IU/ml.[CONCLUSION]1.21strains of measles wild strains for H1a genotype. 2. Contrast Hla reference strains,21strains of measles wild strains of456bp nucleotide fragments, there are7righteous mutations, genetic distance is1-0.017, suggesting the genetic variation is occurring.3. The genetic evolutionary tree, Hla branch tips, there are two small branch is in popular, should be caused take seriously.4. Consideration should be given to the key district (county) intensify the prevention and control of measles, supervision.5. Consideration should be given to the20big age groups reseeding measles vaccine, the women of childbearing age crowd is the key to reseed object.6. In a timely manner to the school-age children immunized to block the spread of measles has very significant effect. |
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