Comparative Study on Molecular Epidemiology of Measles H1a Outbreak and Sporadic Cases in Shandong Province, 2013-2019

doi:10.21203/rs.3.rs-1122872/v1

Background: Measles caused by measles virus (MeV) is a highly contagious viral disease which has also been associated with complications including pneumonia, myocarditis, encephalitis, and subacute sclerosing panencephalitis. The current study collected33 strains from 2013 to 2019 in 13 cities of Shandong province and separate them into 2 group, outbreak cases and sporadic cases. Comparative of genetic characterization between 15 outbreak strains and 18 sporadic strains was made using nucleotide sequencing of the C-terminal region of the N protein gene(N-450).

Results: The results showed that all 33 stains belonged to genotype H1a. The outbreak strains and sporadic strains distribute crossly in phylogenetic tree. Sequences alignment revealed some interesting G and A transversion, which change the amino acids, on sites 1317, 1422, 1543. The nucleotide sequence and amino acid homologies of 15 Shandong outbreak isolates were 98%–100% (0–10 nucleotide variation) and 97.7%–100%, for sporadic isolations, they are 97.3%–100% and 96.6%–100% respectively. The mean evolution rate of 15 outbreak isolations and 18 sporadic isolations was 4.73× 10^-3 and 2.068× 10^-3 substitutions per site per year separately, which is higher than the study made before 2002.

Conclusions: This report compared epidemic and genetic characteristics of outbreak strains and sporadic strains, and raise evolutionary study of sporadic cases may be helpful for discovery of the possibility of outbreak, especially in the stage of measles elimination.

Epigenetics & Genomics

Measles virus

H1a

phylogeny

phylogeography

Measles caused by measles virus is a highly contagious viral disease which has also been associated with complications including pneumonia, myocarditis, encephalitis, and subacute sclerosing panencephalitis. It is one of the leading causes of death among young children worldwide, with a fatality rate as high as 15% in children[1]. Even though a safe and cost-effective vaccine is available, there were 110,000 measles deaths globally in 2017, mostly among children under age 5 years[2]. Measles virus is an enveloped virus with a nonsegmented, negative-sense RNA genome that is 15,894 nucleotides in length. It belongs to the genus Morbillivirus in the Paramyxovirinae sub-family. MeV have 24 genotypes recognized to date (A, B1–B3, C1–C2, D1–D11, E, F, G1–G3 and H1–H2)[3, 4] and there are four predominant measles genotypes currently circulating worldwide: D8, B3, H1 and D4[5]. MeV is genotyped using carboxy-terminal 450 nucleotides of N-region (N-450), the most variable sequence in the MeV genome, or the entire protein-coding region of the H gene [6].

The WHO Measles and Rubella laboratory Network (LabNet) has been established tomonitor progress toward mortality reduction and elimination of measles. Besides serologic testing, another important function of the network is to support the genetic characterization of currently circulating measles viruses. Shandong measles laboratory is amember of the LabNet. The traditional epidemiology characterization had changed in recent years, that is, the season distribution was delayed and the age distribution waschanged; there was great difference among different provinces on the incidence of measles[7]. Outbreak was not the main form of measles in china, and many cases of measles are sporadic. Genetic information is a key factor for improving our understanding of virus transmission pathways[8]. The genetic analysis of the N-450 is a useful tool for establishing whether connections exist between concurrent measles cases [9]. So our study made an effort to seak whether if there is any genetic correlation between the sporadic cases and outbreaks by comparing N-450 region.

Sample collection and virus isolation

We enrolled 15 measles outbreak cases and 18 measles sporadic cases from Shandong measles surveillance system from 2013 to 2019. All the enrolled cases are definited according to the diagnostic criteria of measles. Throat swabs samples were collected from individuals identified as measles after obtaining informed consent from patients or their parents.

Clinical specimens were inoculated on Vero/SLAM (signaling lymphocyte-activation molecule; also known as CDw150) cells[10] and the cells were observed for cytopathiceffect (CPE). Inoculated cells were blind-passaged up to three times before being discarded. Cells were harvested when the CPE was maximal.

sequence amplification and sequencing

All isolations were sequenced and genotyped using the standard protocols. Briefly, viral RNA was extracted from 140 μl Virus culture medium according to the manufacturer’s instructions (Omega, USA). RNA was reconstituted in 60 μl nuclease-free waterand stored at –80°C until tested. Measles virus N gene was amplified using primers;

MeV-F: 5’-GGGAGGCTTGAACTTTGG-3’;

MeV-R: 5’-TCCGTGTCTGAGCCTTGT-3’.

One-step RT-PCR was performed using Takara PrimeScript RT Master Mix. The PCR program was followed by 98°C for 10 s and 30 cycles of 98°C 1 s, 55 °C for 5s, 72 °C 10 s, and a final extension step at 72°C for 1 min was completed in a PCR system (Bio-Rad C1000). The PCR products were purified using the Omega Gel Extraction kit. Sequences of the PCR products were obtained using BigDye terminator chemistry version 3.0 according to the manufacturer’s protocol for both sense and antisense strands on an automated ABI PRISM 3100 DNA Sequencer (PerkinElmer, Beijing, China).

Sequence analysis

Sequences were analyzed using Sequencer (Gene CodesCorporation, Ann Arbor, MI, USA) and aligned using version 7.0 of BioEdit (www.mbio.ncsu.edu/BioEdit/BioEdit.html). Phylogenetic analyses were performed and trees were generated using the Molecular Evolutionary Genetics Analyses (MEGA 7.0) software based on N-450 coding region. Phylogenetic trees were constructed by comparison with the reference strai-ns defined by the WHO previously reported or references committed among 2013-2016 using the neighbor-joining method. The reliability of the groupings was estimated using bootstrap resampling of 1000 replicates. Genebank number of reference sequences use were: LC002659.1, AB824116.1, AB915260.1, KF533141.1, KT031805.1, MH375617.1, MN602401, MK628225,AB915260.1. The evolution rate and molecular clock phylogeny of global measles isolates were inferred using the Bayesian Markov chain Monte Carlo (MCMC) method in BEAST version 1.6.1.

Epidemiological information

Out of the 15 outbreak cases, 10 cases were males and 5 were females. In terms of age, 8 cases were children under 15 years old and 8 adults. For 18 sporadic cases selected in this study, 9 were males and 9 were females; 6 were children under 15 years old and 12 were adults. Except 2 cases were floating population from other provinces, 31 cases involved in this study were resident population. All cases which clinical symptoms informations were available had fever and rash, most of them accompanied with cough, less with Carta Symptoms, Conjunctivitis or Kirschsprung, and rarely with lymph node enlargement or joint pain, only 4 cases accompanied with serious complications (table 1). No matter outbreak cases or sporadic cases, most cases had less than two doses of vaccine or not been vaccinated at all (table 1). In this study, we tried to make sure there are both outbreak strains and sporadic strains in the same isolation time (table.1). The outbreak and sporadic strains we selected from 13cities which have certain consistency in geographical distribution. Separation areas and quantities are shown below (Fig.1).

Sequences alignment

All genetic changes in the Shandong isolates in our study were base substitutions, and no deletion, insertions, or frame-shift mutations, but some interesting mutations were found. Sequences named AB824116.1 which is a reference sequence obtained from Genebank and K217, K314, K403 which were isolated from sporadic cases, together with k295, k322, k333 obtained from outbreaks generated G and A transversions on sites 1317, 1422, 1543(the position were aligned by the measles reference sequence) at the same time comparing to other sequences in our study. All these transversions induced amino changes. Then we aligned these sequences and found all the sequencesseparated in different years, 2013-2015, are totally the same. There are also unique mutation on site 1417 of k540 and 1581 of k314, which all induced amino change. k540 and k314 are all the sporadic case sequence. The nucleotide sequence and amino acid identities of 15 Shandong outbreak isolates were 98%–100% (0–10 nucleotide variation) and 97.7%–100%, for sporadic isolations, they are 97.3%–100% and 96.6%–100% respectively. We separated 33 Shandong isolations into two groups,sporadic group and outbreak group. The distances between the 2 group was 0.008.

Genotype and phylogenetic analysis

PCR products of the 33 viral isolates in the COOH-terminus of the nucleoprotein gene were available and then sequenced. All 33 viral isolations together with 9 reference sequences obtained from Genebank were genotyped as H1a (Fig2.a), using WHO reference strains sequences by neighbor-joining tree. Further phylogenetic analysis weremade between 33 Shandong strains and the 9 references sequences (Fig2.b). From theevolutionary tree, we can see that the outbreak case sequences and the sporadic case sequences are widely distributed. Similarly, strains isolated from different cities cross-distributed, not clustered by city. AB824116.1, K217, K403, k295, k322, k333 which have the totally same sequence formed a separate cluster. Outbreak strains K333, K323, K322 and K330, K352, K384, K385, K462, K514 which isolated from the same year 2015, are on different branches. there are two clusters generated by year. One formed by stains obtained in 2016 and the other 2019.

evolution rate and molecular clock analysis

The evolution rate and molecular clock phylogeny of 33 Shandong isolates were inferred using the Bayesian Markov chain Monte Carlo (MCMC) method in BEAST version 1.6.1[11]. The time of the most recent common ancestor (tMRCA) with 95 % highest posterior density(HPD) was estimated for the global and Shandong clusters. The data were analyzed under the Hasegawa-KishinoYano (HKY) models with gamma distribution of among-site rate variation. The uncorrelated lognormal-distributed (UCLD) relaxed molecular clock, were implemented in our analysis. Both constant and exponential growth (EG) population size coalescent were used as tree prior. The MCMC chain was run for 30,000,000 steps and sampled every 1,000 steps. The first 3,000,000 steps of each run were discarded as burn-in. The molecular clock phylogenetic tree was established too. In the molecular clock phylogenetic tree (Fig3), Shandong isolatesdon’t segregated into a single cluster. Outbreaks and sporadic strains are dispersed inmolecular phylogenetic trees. Although different evolution rates were observed for some different branches, but most different branches have the similar evolution rate. The mean evolution rate of all 33 Shandong isolations with 9 reference isolations was 1.688× 10^-3 substitutions per site per year. The mean evolution rate of 15 outbreak isolations and sporadic isolations was 4.73× 10^-3 and 2.068× 10^-3 substitutions per site per year separately.

China is now in the phase of accelerated measles control and Shandong province wasalso in the phase of measles control. Although from 2016, measles incidence remainslow until 2021, and most of measles are sporadic cases, but before 2020 there are still several outbreaks occurred in Shandong. There are many factors correlated with occurrence of measles outbreak, such as accumulation of susceptible children, seasonal factors, density of population and so on[12–16]. This study made some effort to explored the factors causing measles outbreaks from another perspective: We included 33 isolates from outbreak or sporadic cases from 13 cities of Shandong provinces from 2013 to 2019; And then we compare the outbreak sequences to the sporadic sequences of N-450 to study whether if measles outbreak is related to genetic differences.

As reported previously, measles virus has high genetic stability and there is very little variation in the N sequences of viruses isolated from the same chain of transmission[17]. Moreover, very little genetic changes revealed from the same genotype that were collected several years apart [18, 19]. Similarly, In our study, no matter outbreak sequences or sporadic sequences isolated from different cities or different years have high identities of nucleotide and protein. And the distances between the two group areonly 0.008. These results demonstrate measles strains epidemic in Shandong keep high stability between the outbreak and sporadic strains. However there were some interesting mutations found in our study. Sequences named AB824116.1 which is a reference sequence obtained from Genebank and K217, K314, K403 which were isolated from sporadic cases, together with k295, k322, k333 obtained from outbreaks generated G and A transversions on three sites (site 1317, 1422, 1543) at the same time. K217 were separated in 2013 from sporadic case, then 2014-2015 the outbreak cases k295, k322, k323, k333 were explored. This may suggest that when several strains with the same multiple mutations appears, we should be more alert to outbreaks.

On phylogenetic tree, AB824116.1, K217, K403,K295, K322, K333 which have the totally same sequence, islated from different cities or years, formed a cluster. However outbreak strains K333, K323, K322 and K330, K352, K384, K385, K462, K514 which isolated from the same year 2015, are on different branches. These above suggest the complexity of measles transmission in Shandong: there are both single-chain transmission across year and multi-chain transmission in the same year in Shandong province.

The comparative of outbreak and sporadic strains in evolution rate was made by the Bayesian Markov chain Monte Carlo (MCMC) method in BEAST, and the result shows the mean evolution rate of outbreak isolations and sporadic isolations was 4.73× 10^-3 and 2.068× 10^-3 substitutions per site per year. Although the difference of evolution rate between outbreak and sporadic strains is small, but it is higher than previous study( Rima et al. (1997) estimated the rate of mutation for MeV in the field to be 5 ×10^-4 substitutions per base per year[18] and a similar estimate of 4 ×10^-4 was made by Jenkins et al. (2002)[20]). Whether measles evolved faster recent years than previous years, and whether outbreaks always evolved a bit faster than sporadic cases. All of these questions require more cases and further studies to answer in our next step study.

Annual measles outbreaks with high vaccination rate also continues to occur. Although these outbreaks typically involve importation and mostly affect unvaccinated individuals, there are surprisingly high numbers of vaccine failure among one- and two-dose recipients of measles vaccine who were infected (approximately 2 – 12% for children immunized at/around one year of age [21–54]. Similarly with previous study, in our study, all cases no matter outbreak or sporadic had less than two dose measles vaccines.

Although in our comparative study, there was no genetic difference were found between the outbreak strains and the sporadic strains, but we found that both the study of the outbreak cases and the evolutionary study of the sporadic cases are important. Evolutionary study of the sporadic cases may have a certain value for the discovery of the outbreak hazard in the surveillance of measles, especially in the stage of measles elimination. There may be accumulation of sporadic in the early stages of each outbreak.

MeV: Measles virus; N-450: carboxy-terminal 450 nucleotides of N-region; SLAM: signaling lymphocyte-activation molecule; CPE:cytopathic effect; MEGA: Molecular Evolutionary Genetics Analyses; MCMC: Markov chain Monte Carlo; tMRCA: time of the most recent common ancestor; HPD: highest posterior density; HKY: Hasegawa-KishinoYano; UCLD: uncorrelated lognormal-distributed; EG: exponential growth.

Acknowledgements

We would like to thank the staff of EPI division in Shandong Center for Disease Control and Prevention for their contribution in data and sample collection.

Funding

This study was supported bya grant from Medical and Health Science and Technology Development Plan Program of Shandong (012051301) and a grant from Taishan Scholar Program of Young Experts(tsqn.202103187).

Availability of data and materials

Newly generated N-450 sequences of Shandong measles virus isolates have been submitted to GenBank, under the following accession numbers: OL807629-OL807661. All sequences data that support the findings of this study have been deposited in GeneBank.

Authors’ contributions

SW, CW, LZ and AX conceived the study and drafted the paper, XL, PX, YL and QX gathered and analyzed the data, and MC, ZT participated in RNA extraction. SW and CW are co-first authors. All authors read and approved the final manuscript.

Competing interests

The authors declare that they have no competing interests.

Consent for publication

Not applicable.

Ethics approval and consent to participate

All protocols for this study were reviewed and approved by Ethics Review Committee of the Shandong Center for Disease Control and Prevention (No.2021-6), and the study was carried out in accordance with the principles of the Declaration of Helsinki. Written informed consents for the use of their clinical samples were obtained from all subjects (the legal guardians of the patients and contacts).

Nasamon Wanlapakorn, Rujipat Wasitthankasem, Preeyaporn Vichaiwattana, Chompoonut Auphimai, Pornsak Yoocharoen, Sompong Vongpunsawad, Yong Poovorawan. Antibodies against measles andrubella virus among different age groups in Thailand: A population-based serological survey. PLoS ONE 14(11): e0225606. https://doi.org/10.1371/journal.pone.0225606
The World Health Organization Fact sheet. Measles Available from: https://www.who.int/en/newsroom/fact-sheets/detail/measles.
WHO Global Surveillance. Weekly Epidemiological Record Relevé Épidémiologique Hebdomadaire; World Health Organization: Geneva, Switzerland, 2012; Volume 204, pp. 73–80.
Rota, P.A.; Brown, K.; Mankertz, A.; Santibanez, S.; Shulga, S.; Muller, C.P.; Hübschen, J.M.; Siqueira, M.; Beirnes, J.; Ahmed, H.; et al. Global Distribution of Measles Genotypes and Measles Molecular Epidemiology.J. Infect. Dis. 2011, 204, S514–S523.
Measles Nucleotide Surveillance database (MeaNS). Available at www.who-measles.org (Accessed 16 July 2018).
Rima, B.K.; Earle, J.A.; Yeo, R.P.; Herlihy, L.; Baczko, K.; ter Meulen, V.; Carabaña, J.; Caballero, M.; Celma, M.L.; Fernandez-Muñoz, R. Temporal and geographical distribution of measles virus genotypes. J. Gen. Virol. 1995, 76 Pt 5, 1173–1180.
Yan Zhang, Yixin Ji, Xiaohong Jiang, Songtao Xu, Zhen Zhu, Lei Zheng, Jilan He, Hua Ling, Yan Wang, Yang Liu, Wen Du, Xuelei Yang, Naiying Mao, Wenbo Xu. Genetic characterization ofMeasles Viruses in China, 2004. Virology Journal 2008, 5:120.
Kim Y-J, Kang HJ, Kim S-J, Lee HM, Kim SS. 2019. Complete genome sequences of
measles virus genotype D8 isolates from South Korea in 2016. Microbiol Resour Announc 8:e00032-19. https://doi.org/10.1128/MRA .00032-19.
Kobune FSH, Sugiura A: Marmoset lymphoblastoid cells as a sensitive host for isolation of measles virus. J Virol 1990.
Drummond AJ, Rambaut A (2007) BEAST: Bayesian evolutionary analysis by sampling trees. BMC Evol Biol 7:214
Conlan AJ, Grenfell BT: Seasonality and the persistence and invasion of measles. Proc Biol Sci, 2007; 274(1614): 1133–41
Huang J, Ruan S, Wu X, Zhou X: Seasonal transmission dynamics of measles in China. Theory Biosci, 2018; 137(2): 185–95
Ma C, Hao L, Zhang Y et al: Monitoring progress towards the elimination of measles in China: An analysis of measles surveillance data. Bull World Health Organ, 2014; 92(5): 340–47
Ma Y, Zhou J, Yang S et al: Assessment for the impact of dust events on measles incidence in western China. Atmospheric Environment, 2017; 157: 1–9
Li S, Ma C, Hao L et al: Demographic transition and the dynamics of measles in six provinces in China: A modeling study. PLoS Med, 2017; 14(4):e1002255
Rota, P.; Featherstone, D.; Bellini, W. Molecular epidemiology of measles virus. Curr. Top. Microbiol. Immunol. 2009, 330, 129–150.
Rima, B.K.; Mcferran, N.V. Dinucleotide and stop codon frequencies in single-stranded RNA viruses. J. Gen. Virol. 1997, 78, 2859–2870.
El Mubarak, H.S.; van de Bildt, M.W.G.; Mustafa, O.A.; Vos, H.W.; Mukhtar, M.M.; Ibrahim,S.A.; Andeweg, A.C.; El Hassan, A.M.; Osterhaus, A.D.M.E.; de Swart, R.L. Genetic characterization of wild-type measles viruses circulating in suburban Khartoum, 1997–2000. J. Gen. Virol. 2002, 83, 1437–1443.
Jenkins, G.M.; Rambaut, A.; Pybus, O.G.; Holmes, E.C. Rates of molecular evolution in RNA viruses: A quantitative phylogenetic analysis. J. Mol. Evol. 2002, 54, 156–165.
Meissner HC, Strebel PM, Orenstein WA. Measles vaccines and the potential for worldwide eradication of measles. Pediatrics. 2004;114(4):1065–1069.
Elliman D, Sengupta N. Measles. Curr OpinInfect Dis. 2005;18(3):229–234.
Haralambieva IH, Ovsyannikova IG, Pankratz VS, et al. The genetic basis for interindividual immune response variation to measles vaccine: new understanding and new vaccine approaches.Expert Review of Vaccines. 2013 1;12(1):57–70.
Moss W Measles in Vaccinated Individuals and the Future of Measles Elimination. Clin Infect Dis. 2018; 67: 1320–1321.
Moss WJ. Measles control and the prospect of eradication. Current Topics in Microbiology andImmunology. 2009;330:173–189.
Measles Fact Sheet No. 286. http://www.who.int/en/news-room/fact-sheets/detail/measles 2018.
Parker Fiebelkorn A, Redd SB, Gallagher K, et al. Measles in the United States during the postelimination era. J Infect Dis. 2010;202(10):1520–1528.
Poland GA, Jacobson RM, Thampy AM, et al. Measles re-immunization in children seronegative after initial immunization. JAMA. 1997;277:1156–1158.
Seward JF, Orenstein WA. A rare event: A measles outbreak in a population with high 2-dosemeasles vaccine coverage. Clinical Infectious Diseases. 2012;55(3):403–5.
De Serres G, Boulianne N, Defay F, et al. Higher risk of measles when the first dose of a 2-dose schedule of measles vaccine is given at 12-14 months versus 15 months of age. Clin Infect Dis. 2012;55(3):394–402.
Poland GA, Jacobson RM. Failure to reach the goal of measles elimination. Apparent paradox of measles infections in immunized persons. Arch In Med. 1994;154:1815–1820
Paunio M, Peltola H, Valle M, et al. Explosive school-based measles outbreak: intense exposure may have resulted in high risk, even among revaccinees. Am J Epidemiol. 1998; 148(11): 1103–1110.
Mathias RG, Meekison WG, Arcand TA, et al. The role of secondary vaccine failures in measles outbreaks. Am J Public Health. 1989;79:475–478.
Sugerman DE, Barskey AE, Delea MG, et al. Measles outbreak in a highly vaccinated population, San Diego, 2008: role of the intentionally undervaccinated. Pediatrics. 2010;125(4):747–755.
Pannuti CS, Morello RJ, Moraes JC, et al. Identification of primary and secondary measles vaccine failures by measurement of immunoglobulin G avidity in measles cases during the 1997 Sao Paulo epidemic. Clin Diagn Lab Immunol. 2004; 11(1):119–122.
Hickman CJ, Hyde TB, Sowers SB, et al. Laboratory characterization of measles virus infection in previously vaccinated and unvaccinated individuals. J Infect Dis. 2011;204 Suppl 1:S549–S558.58
Glass K, Grenfell BT. Waning immunity and subclinical measles infections in England. Vaccine. 2004;22(29-30):4110–4116.
Mossong J, Nokes DJ, Edmunds WJ, et al. Modeling the impact of subclinical measles transmission in vaccinated populations with waning immunity. Am J Epidemiol. 1999; 150(11): 1238–1249.
Whitaker JA, Poland GA. Measles and mumps outbreaks in the United States: Think globally, vaccinate locally [Editorial], Vaccine. 2014 8 20;32(37):4703–4.
Papania MJ, Wallace GS, Rota PA, et al. Elimination of endemic measles, rubella, and congenital rubella syndrome from the Western hemisphere: the US experience [Historical Article], JAMA Pediatr. 2014 2;168(2):148–55.
Notes from the field: measles outbreak associated with a traveler returning from India - NorthCarolina, April-May 2013. MMWR. 2013 9 13;62(36):753.
Notes from the field: measles outbreak among members of a religious community - Brooklyn, New York, March-June 2013. MMWR. 2013 9 13;62(36):752–3.
Zipprich J, Hacker JK, Murray EL, et al. Notes from the field: measles - California, January 1-April 18, 2014. MMWR. 2014 4 25;63(16):362–3.
Notes from the field: measles outbreak—Indiana, June-July 2011. Morbidity and Mortality Weekly Report. 2011;34:1169.
Notes from the field: Multiple cases of measles after exposure during air travel--Australia and New Zealand, January 2011. MMWR. 2011; 60(25):851.
Notes from the field: measles outbreak--Hennepin county, Minnesota, February--March 2011. MMWR. 2011;60(13):421.
Katz SL, Hinman AR. Summary and conclusions: measles elimination meeting, 16-17 March J Infect Dis. 2004; 189 Suppl ES43–S47.
Measles once again endemic in the United Kingdom [News], Euro Surveill. 2008 7 3; 13(27). Measles - United States, 2011. MMWR. 2012;61:253–257.
Rosen JB, Rota JS, Hickman CJ, et al. Outbreak of measles among persons with prior evidence of immunity, New York City, 2011. Clinical infectious diseases : an official publication of the Infectious Diseases Society of America. 2014 5;58(9): 1205–10. doi: 10.1093/cid/ciul05.
Haralambieva IH, Kennedy RB, Ovsyannikova IG, et al. Variability in Humoral Immunity to Measles Vaccine: New Developments. Trends Mol Med. 2015 12;21(12):789–801.
Cherry JD, Zahn M Clinical Characteristics of Measles in Previously Vaccinated and Unvaccinated Patients in California. Clin Infect Dis. 2018;67(9): 1315–1319.
Boulianne N, De Serres G, Ratnam S, et al. Measles, mumps, and rubella antibodies in children 5-6 years after immunization: effect of vaccine type and age at vaccination. Vaccine. 1995;13:1611–1616.
Christenson B, B”ttiger M Measles antibody: comparison of long-term vaccination titres, early vaccination titres and naturally acquired immunity to and booster effects on the measles virus. Vaccine. 1994;12:129–133.
Mitchell LA, Tingle AJ, D cD, et al. Serologic responses to measles, mumps, and rubella (MMR) vaccine in healthy infants: Failure to respond to measles and mumps components may influence decisions on timing of the second dose of MMR. Canadian Journal of Public Health. 1998;89(5):325–328.

Table. 1 Symptoms and measles vaccination of measles cases together with the isolation time

code

fever

rash

cough

Carta Symptoms

Conjunc

-tivitis

Kirschs

-prung

lymph node enlargement

joint pain

Other complications

measle vaccine

Isolation time(year)

Outbreak cases

k295

✓

×

-

2 dose

2014

k322

✓

×

-

2015

k323

✓

×

✓

×

-

2015

k330

-

2015

k333

-

2015

k352

✓

×

-

0 dose

2015

k384

✓

-

2015

k385

✓

×

✓

×

-

2015

k462

✓

×

✓

×

-

0 dose

2015

k514

✓

×

✓

×

-

1 dose

2016

k515

✓

×

-

0 dose

2016

k516

✓

×

✓

×

-

2016

k662

✓

×

✓

×

pneumonia

0 dose

2019

k663

✓

×

pneumonia

1 dose

2019

k664

✓

×

pneumonia

1 dose

2019

Sporadic cases

k217

✓

×

-

1 dose

2013

k224

-

2013

k229

✓

×

-

1 dose

2013

k309

-

2014

k311

✓

×

✓

×

-

2014

k314

✓

×

-

0 dose

2014

k329

✓

×

-

0 dose

2015

k372

✓

×

-

0 dose

2015

k378

✓

×

✓

×

-

2015

k389

✓

×

-

2015

k398

✓

×

✓

×

-

0 dose

2015

k403

-

2015

k463

✓

×

-

0 dose

2015

k483

✓

×

✓

×

-

0 dose

2016

k540

✓

×

bronchitis

-

2016

k665

-

2019

k666

✓

×

-

2019

k667

✓

×

-

2019

No competing interests reported.

Comparative Study on Molecular Epidemiology of Measles H1a Outbreak and Sporadic Cases in Shandong Province, 2013-2019

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Abstract

Figures

Introduction

Material And Methods

Results

Discussion

Abbreviations

Declarations

References

Tables

Additional Declarations

Status:

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