Study On The Influencing Factors And Control Strategy Of Measles In Anhui Province

BackgroundMeasles is a highly contagious disease caused by the RNA virus of the paramyxovirus class,measles virus has only one serotype,the genome is a non-segmented single-stranded(-)RNA with a total length of about 16 kb,contains six structural genes,encoding six major structural proteins: nucleoprotein(N),phosphoprotein(P),matrix protein(M),fusion protein(F),hemagglutinin(H),RNA-dependent RNA polymerase(L).In the 1980 s,countries have discovered antigenic drift due to mutations in measles virus.From 2000 to 2015,the incidence of the global measles annual report fell by 75%from 146 to 36 patients per million,while the number of measles deaths decreased by79%(from 651600 to 134200 cases).Nevertheless,there are still about 360 children died of measles every day in the world.In order to reduce the high incidence of measles,the World Health Organization(WHO)has established a goal that at least five regions have to achieve measles eradication by 2020,and all six WHO regions have established targets to eliminate measles by 2020 or before.The number of measles cases reported in China in 2015 was 42361 cases,there were 32 deaths,the reported incidence of measles was 3.1091 cases / 100,000,the mortality rate was 0.0023 / 100,000.According to the data from "China Disease Prevention and Control Information System",a total of 3335 cases of measles reported in Anhui Province in 2015,the incidence rate was 5.4856 / 10 million,there were 2 deaths,the number of cases increased by 2.32 times compared with the same period in 2014(1005 cases),From the age distribution,? 7 months of age,8 months to 14 years old children and ? 15 years old adults accounted for about one-third of the number respectively.In order to comprehensively explore the causes of high measles,this group conducted a case-control study on the influencing factors of measles in different age groups in Anhui Province.The factors influencing the incidence of measles in all age groups were analyzed.At the same time,the isolates N and H genes and then compared with the WHO reference strain and the sequence of the Chinese vaccine strains.The molecular type,gene homology,amino acid variation and glycosylation status of the measles strains in Anhui were obtained.In order to explore the accuracy of MCV immunization history of measles cases in China's disease prevention and control information system,this study will compare it with the "Immune Planning Information Management System of Anhui Province" in order to explore the protection of measles vaccine in this province and to identify the source and epidemic characteristics of virus.In order to better explain the safety of MCV vaccination in Anhui Province,the task force analyzed the AEFI of MCV vaccination reported in Anhui Province in detail.It is essential for child caregivers to promote awareness of measles and MCV knowledge,and grassroots medical staff plays a very important role in advocacy work.Therefore,this study carried out a survey on awareness of measles awareness among primary care workers and child guardians the knowledge of measles knowledge,to provide the basis for the next step in the development of measles intervention strategy.The Delphi method originated in the 1960 s by RAND Corporation,the first to be used to predict the impact of science and technology on society.Most of the Delphi methods were designed to explore reliable creative ideas or to develop strategies aspects of information integration.This method is suitable for the efficient exploration of various possible strategies,Delphi is a system to collect expert advice,there is no face to face interference,this method contains three basic characteristics,firstly,anonymity: experts do not know each other;secondly,a few rounds of feedback,Thirdly,the statistical analysis of expert opinions,such as the weight of the score,the first or third quartile of the score,or the coordination of the expert opinion,and so on.There should be at least10-15 experts involved and at least two rounds of expert advice.Finally,a more conclusive conclusion can be drawn.Finally,the research group combined all the above studies,and used the Delphi method to discuss the measles comprehensive intervention strategy.Part ? A Case Control Study on the Influencing Factors of Measles in Anhui ProvinceObjectives In order to comprehensively explore the cause of high incidence of measles,this group conducted a case-control study on the influencing factors of measles in Anhui province.The factors influencing the incidence of measles in each age group were analyzed respectively,which provided scientific basis for controlling and finally eliminating measles.MethodsFrom May 2015 to June 2016,selected "?7 months old baby group","8 months old-14 years old children group" and "?15 years old adult group" three age groups newly reported measles laboratory confirmed cases in the "Chinese disease prevention and control information system" as case group,chose the same age groups of 232 people respectively without measles within three months as control group.The data of demographic,physical,family,history,medical history and history of exposure were collected,and the influencing factors of measles were analyzed by logistic single factor and multivariate analysis.Results(?)Influencing factors of measles in ?7 months old baby group: measles patient exposure(OR(95%CI)= 39.721(12.603-125.184)(OR),preterm birth(95%CI)=14.896(3.756-59.074)),6-7 months(OR(95%CI)= 5.255(3.092-8.931)(OR),grandparents care(95%CI)= 3.376(1.668-6.834)),living in the urban fringe(OR(95%CI)= 3.035(1.236-7.454)),having a history of going out(OR(95%CI)= 2.66(1.302-5.435),hospital exposure history(OR(95%CI)= 2.588(1.496-4.476))and male(OR(95%CI)= 2.118(1.261-3.555))are the risk factors;having brothers and sisters(OR(95%CI)= 0.464(0.276-0.781))and breastfeeding(OR(95%CI)= 0.297(0.153-0.574))were the protective factors.(?)Influencing factors of measles in 8 months old-14 years-old baby group: measles patient exposure(OR(95% CI)= 8.046(2.761-23.451)),living in urban and rural fringe(OR(95% CI)= 3.347(1.365-8.204)),preterm birth(OR(95% CI)=3.171(1.185-8.487)),hospital exposure history(OR(95%CI)= 3.089(1.813-5.263)),boys(OR(95%CI)= 1.913(1.104-3.313))were the risk factors for its incidence;breastfeeding(OR(95%CI)= 0.313(0.175-0.558)),having a vaccination certificate(OR(95%CI)= 0.192(0.052-0.707))and MCV immunization(OR(95% CI)= 0.050(0.025-0.101))were the protective factors.Immunological history analysis showed that the cases with no MCV vaccination were up to 63.79%,while the controls were only4.74% without MCV.The reasons why they were without MCV vaccination was that97.83% of the 8-month-old to 14 years old age children due to vaccinee,and less than3% of the reasons for vaccination side,such as irrational outpatient or MCV in short supply and so on.And the reasons for the most of the recipients were vaccination contraindications,such as children in the cold when an appointment time and other reasons failed to vaccinate MCV,followed by caregivers no time to bring children to vaccination and that measles is a minor illness,does not matter vaccination or not and so on.(?)Influencing factors of measles in ?15 years old age group: measles patient exposure(OR(95% CI)= 42.580(5.559-326.158)),hospital exposure history(OR(95%CI)= 6.225(3.896-9.946)),living in urban and rural fringe(OR(95%CI)=5.564(2.485-12.459)),migrant population(OR(95%CI)= 3.900(1.633-9.311)),male(OR(95% CI)= 5.564(2.485-12.459),having a history of going out(OR(95% CI)=1.898(1.058-3.405))were risk factors for its incidence;and children <15 years old was the protective factor(OR(95% CI)= 0.383(0.216-0.682)).Conclusion According to the results of this study,we proposed to ensure 95% vaccination rate of two doses of MCV and timely vaccination of the first dose,to control the occurrence of nosocomial infection,to promote eugenics,breastfeeding,and avoid crowded places in high incidence seasons of measles.Part ? Analysis of Characteristics for N,H genes of Measles Virus,MCV Immunization Situation of Measles Cases and MCV safety in Anhui ProvinceObjectives To evaluate the protective effect of measles vaccine in this province,to identify the source and epidemiological characteristics of the virus and its MCV safety,to explore the accuracy of MCV immunization history and the occurrence of MCV-related measles in measles cases in China's disease prevention and control information system.Methods The isolates of N and H genes were isolated from the laboratory,and then compared with the WHO reference locus and the sequence of the Chinese vaccine strains.The molecular type and gene homology of the measles strains in Anhui were obtained,Amino acid mutation and glycosylation site.The MCV immunization history of measles cases in China's disease prevention and control information system was compared with that of Anhui Province's Child Vaccination Information Management System.To analyze the AEFI of MCV in Anhui Province.Results(?)The wild-type measles virus in Anhui region were all H1 a gene subtype;There was little difference in the nucleotide sequence between the isolates and the isolates of H1 a gene subtype reference strain China93-2,H protein amino acid mutation at position 240 leads to a deletion of a glycosylation site.(?)The vaccination rate of MCV in CISDCP(17.94%)was slightly higher than that in AISIM(12.79%),the difference was statistically significant(c2=11.881,P=0.001).(?)The measles occurred in the first week after vaccination of the first dose of MCV(MCV1),accounting for 39.32%,occurred in the second week,accounting for 23.93%,No.of measles cases occurred within 2 weeks after vaccination with MCV1 accounted for 60% of within 15 weeks after vaccination.(?)The total incidence of AEFI for MCV in Anhui Province from 2015 to 2016 was446.32 per million,and the incidence of severe AEFI was 2.85 per million.Conclusion Popular type of measles virus in Anhui Province at this stage was the main popular type in China.There was no significant variation in the nucleotide sequence between the isolates and the isolates of H1 a gene subtype reference strain China93-2.H protein amino acid mutation at position 240 leads to a loss of a glycosylation site,which may lead to changes in immunogenicity,leading to a decrease in vaccine protection.The accuracy of MCV immunization in CISDCP should be strengthened.Emphasis on measles cases occurring within 2 weeks after vaccination of MCV1;AEFI for MCV in2015-206 in Anhui Province is within safety limits.Part ? Investigation on Knowledge Rate of Measles Knowledge among Primary Medical Personnels and Child GuardiansObjectives To understand the knowledge rate of measles knowledge among primary care workers and children guardians,and to provide reference for the development of measles intervention strategy by Delphi method.Methods Investigated all the participants of the county-level CDC staff when they came to attend the province's immunization planning training courses;selected eight counties according to the incidence and geographical location,randomly selected two townships in each county,selected eight medical staff of township hospitals and ten medical staff of village health clinics in each township to carry out investigation of awareness of measles knowledge of primary medical staff;selected 40 child guardians in each township's outpatient clinic to carry out the survey;SPSS16.0 software statistical analysis,count data was compared using c2 test,measurement data was compared using t test or analysis of variance,P <0.05 showed that the difference was statistically significant.Results(?)A total of 433 grassroots medical personnel were investigated,including 125county-level disease control institutions,127 township hospitals,181 village health clinics,65.22% awareness of measles knowledge and medical awareness of measles at county level(c2=43.827,P<0.001),measles knowledge awareness rate of(assistant)practicing physician was higher than that of non-practicing physician medical staff(c2=30.307,P<0.001);The lowest awareness item is that how many serotypes of measles has,only 33.03% of people knew that only one serum type.(?)A total of 669 children guardian,527 parents,136 grandparents,and 6 others were investigated.The total awareness rate of measles knowledge was 40.54% and the parents' awareness rate was higher than that of grandparents(c2=82.371,P<0.001);The lowest awareness rate was how many days measles patients to be isolated after rash coming out,only 8.07% of child guardians knew it was 5 days.Conclusion Grassroots medical personnel,child guardians have a low awareness rate of measles knowledge,imbalance of the awareness,we should focus on the knowledge points,to carry out effective interventions to key populations,to improve knowledge awareness rate of grassroots medical staff and child guardian measles.Part ? Study of Measles Control Strategy by Delphi methodObjectives Using the Delphi method to develop a measles intervention strategy to provide scientific basis for the development of measures for the health sector.Methods According to the results of "case-control study of measles influencing factors","measles virus gene,MCV immunization history and safety analysis","grassroots medical staff,child guardian knowledge of measles knowledge",designed the measles intervention strategy expert consultation form through expert interviews,after two rounds of Delphi method,including 22 experts,formated the measles intervention strategy list.Using SPSS 16.0 statistical analysis,measurement data was calculated with mean,standard deviation,enumeration data was calculated with rate or constituent ratio.Evaluated expert consistency using the Kendall coordination coefficient.Results(?)The first round of expert consultation results: the positive coefficient of experts is100%,the authority coefficients were all higher than 0.7,the evaluation the coordination coefficient of the importance is 0.294,the coordination coefficient of the feasibility is 0.213,after the first round of consultation,6 Level 1 entries and 29 Level2 entries were retained;(?)The second round of expert consultation results: the positive coefficient of experts was 100%,the coordination coefficient of the importance was 0.302,the coordination coefficient of the feasibility was 0.297,after two rounds of consultation,5 Level 1entries and 17 Level 2 entries were retained.Conclusion According to the results of expert consultation,the control strategy of measles was formulated,including 5 Level 1 entries and 17 Level 2 entries,which provided scientific basis for the elimination of measles in the health sector.