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China has been working towards measles elimination, but in 2017, measles outbreaks occurred in Ganzi and Aba prefectures of Sichuan province, representing 95% of all provincial cases and jeopardizing measles elimination. During March and April 2017, high-performing prefectures were paired with outbreak and other interested counties to jointly conduct a measles-rubella (MR) catch-up campaign, build population immunity, and strengthen the counties' programs. House-to-house search identified 88,383 children in Ganzi that lacked MCV vaccination; 85,144 (96.34%) were vaccinated. Search identified 33,683 children in Aba who were not vaccinated against measles; 33,074 (98.19%) were vaccinated. The supporting prefectures helped install Immunization Information Systems and enroll unvaccinated children into the immunization program.The outbreak ended within a month and incidence has remained low for the subsequent six years. A paired catch-up campaign represents an effective model of using measles elimination strategies to strengthen local immunization programs for long-term program effectiveness. [ABSTRACT FROM AUTHOR]

Aim: This study aimed to explore the spatial and temporal characteristics of emerging airborne viral infectious diseases outbreaks worldwide. Subject and methods: We conducted a systematic literature review on outbreaks of emerging airborne viral infectious diseases and calculated outbreak number and intensity at the country level. Fisher's exact test was used to compare the viral infectious diseases outbreaks in different income-level regions. To identify the major airborne viral infectious diseases outbreaks, we ranked and extracted the leading viral infectious diseases in outbreak number and intensity in each country by year. Results: A total of 2505 outbreaks were reported from 1873 to 2021 across 2010 studies. There were 47 countries (47/130, 36.15%) with more frequent emerging airborne viral infectious disease outbreaks (more than nine outbreaks), and these countries mainly distributed in high-income regions (22/47 countries, 46.81%, p < 0.05), especially in Western Europe (14/47 countries, 29.79%, p < 0.05). The number of overall outbreaks was more in the United States and China than in other countries in different years. Outbreaks of measles and influenza are always frequent and intense. Highly pathogenic human coronaviruses infection caused short-term pandemics during which their outbreak number and intensity exceeded other viruses. Rift valley fever outbreaks in the human population are spreading outside of Africa through the flow of goods and travelers. Conclusion: Countries in high-income regions reported more emerging airborne viral infectious diseases outbreaks, especially in the Western European region, the United States, and China. It is urgent to strengthen collaborative surveillance of emerging airborne viruses, cross-border flow of goods and travelers, and ecological environment to avoid the spread of viral infectious diseases outbreaks worldwide. [ABSTRACT FROM AUTHOR]

Background: Measles-containing vaccine (MCV) has been effective in controlling the spread of measles. Some countries have declared measles elimination. But recently years, the number of cases worldwide has increased, posing a challenge to the global goal of measles eradication. This study estimated the relationship between meteorological factors and measles using spatiotemporal Bayesian model, aiming to provide scientific evidence for public health policy to eliminate measles. Methods: Descriptive statistical analysis was performed on monthly data of measles and meteorological variables in 136 counties of Shandong Province from 2009 to 2017. Spatiotemporal Bayesian model was used to estimate the effects of meteorological factors on measles, and to evaluate measles risk areas at county level. Case population was divided into multiple subgroups according to gender, age and occupation. The effects of meteorological factors on measles in subgroups were compared. Results: Specific meteorological conditions increased the risk of measles, including lower relative humidity, temperature, and atmospheric pressure; higher wind velocity, sunshine duration, and diurnal temperature variation. Taking lowest value (Q1) as reference, RR (95%CI) for higher temperatures (Q2–Q4) were 0.79 (0.69–0.91), 0.54 (0.44–0.65), and 0.48 (0.38–0.61), respectively; RR (95%CI) for higher relative humidity (Q2–Q4) were 0.76 (0.66–0.88), 0.56 (0.47–0.67), and 0.49 (0.38–0.63), respectively; RR (95%CI) for higher wind velocity (Q2–Q4) were 1.43 (1.25–1.64), 1.85 (1.57–2.18), 2.00 (1.59–2.52), respectively. 22 medium-to-high risk counties were identified, mainly in northwestern, southwestern and central Shandong Province. The trend was basically same in the effects of meteorological factors on measles in subgroups, but the magnitude of the effects was different. Conclusions: Meteorological factors have an important impact on measles. It is crucial to integrate these factors into public health policies for measles prevention and control in China. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to analyze the epidemiological and clinical characteristics of measles in Jinan, Shandong, China, over a 32-year stage to facilitate measles prevention in the future. Methods: Data on measles cases from 1991 to 2022 were obtained from the public health department and medical records of patients at Shandong Public Health Clinical Center. Retrospective analysis was conducted on the distribution of measles cases in different years, months, and age groups, and observation of the differences in clinical manifestations and complications among different age groups. Results: From January 1991 to December 2022, 7531 measles cases were recorded at Shandong Public Health Clinical Center. During the 32-year period, there were two outbreaks of measles in 2008 and 2016, respectively. During the COVID-19 pandemic period from 2020 to 2022, the number of cases reached the lowest point in the past 30 years. The number and percentage of cases in the 0– 1y groups was significantly higher than in other age groups, and 97.75% patients in this group did not receive measles vaccine. Complications such as pneumonia and myocarditis appeared more frequent in patients under 12 years of age, but liver function damage is more common in adult patients. Conclusion: Although the measles epidemic has been greatly controlled since the use of measles vaccine, intermittent outbreaks still exist, so there is still a long way to go to eliminate measles. The proportion of infants under the age of 1 without measles vaccine and adults over 24 years old accounts for nearly 80% of the total. This group of people should be of concern, and feasible measures should be designated to protect these susceptible populations. [ABSTRACT FROM AUTHOR]

Characterizing the long-term kinetics of maternally derived and vaccine-induced measles immunity is critical for informing measles immunization strategies moving forward. Based on two prospective cohorts of children in China, we estimate that maternally derived immunity against measles persists for 2.4 months. Following two-dose series of measles-containing vaccine (MCV) at 8 and 18 months of age, the immune protection against measles is not lifelong, and antibody concentrations are extrapolated to fall below the protective threshold of 200 mIU/ml at 14.3 years. A catch-up MCV dose in addition to the routine doses between 8 months and 5 years reduce the cumulative incidence of seroreversion by 79.3–88.7% by the age of 6 years. Our findings also support a good immune response after the first MCV vaccination at 8 months. These findings, coupled with the effectiveness of a catch-up dose in addition to the routine doses, could be instrumental to relevant stakeholders when planning routine immunization schedules and supplemental immunization activities. The timing of measles vaccination in infants affects the risk of infection in young children and the duration of protection provided. Here, the authors investigate optimal vaccination timing by characterising antibody kinetics following different vaccine schedules in two cohorts of children in southern China. [ABSTRACT FROM AUTHOR]

Background To provide useful insights into measles elimination progress in China, measles surveillance data were reviewed, and the transmission patterns of measles viruses circulating in China during 1993–2021 were analyzed. Methods Measles incidence data from the National Notifiable Disease Reporting System of the China Center for Disease Control and Prevention were analyzed. A total of 17 570 strains were obtained from 30 of 31 provinces in mainland China during 1993–2021. The recommended genotyping window was amplified. Genotyping analysis was conducted for comparison with the reference strains. Phylogenetic analyses were performed to identify genetic relationships among different lineages within the genotypes. Results With high coverage of routine immunization and intensive supplementary immunization activities, measles incidence has shown a downward trend since 1993, despite 2 resurgences, reaching a historic low level in 2020–2021 (average 0.5 per million). During 1993–2021, 9 genotypes including domestic genotype H1; imported genotypes B3, D4, D8, D9, D11, G3, and H2; and vaccine-associated genotype A were identified. Among them, the genotype H1 strain circulated endemically in China for more than 25 years; the last strain was detected in Yunnan Province in September 2019. Multiple imported genotypes have been identified since 2009 showing different transmission patterns. Since April 2020, no imported strains have been detected, while vaccine-associated genotype A continues to be detected. Conclusions The evidence of low incidence during 2020–2021 and virological surveillance data in this study confirm that China is currently approaching measles elimination. [ABSTRACT FROM AUTHOR]

Measles, caused by measles virus (MeV), has not been eradicated in many regions and countries, threatening human health. Thus, it is beneficial for measles elimination to understand measles epidemiology and molecular evolution of key viral genes, such as nucleoprotein (N) gene. Based on public data, measles epidemiological information and MeV N gene sequences reported in Shandong Province, China were comprehensively collected and systematically analyzed. The results showed a positive correlation between population density and measles incidence (r = +0.31), while negative correlations were found between measles incidence and healthcare condition (r = −0.21) as well as average routine vaccination rate (r = −0.11). Additionally, the predominant lineage of MeV in Shandong was formed by genotype H1 strains, and the time of the most recent common ancestor of the N gene of MeV genotype H1 in Shandong traced back to 1987 (95% highest posterior density, 1984–1990) with relatively rapid evolution (mean rate, 1.267 × 10−3 substitutions/site/year). The genetic diversity of MeV N gene increased with the substantial emergence of major divergent clades of genotype H1 before 2005 and then remained relatively high and stable. In summary, these findings provided a significant insight into the measles elimination. [ABSTRACT FROM AUTHOR]

The waning of maternal antibodies may cause infants to lose protection against measles before receiving measles-containing vaccine (MCV). The aim of this study is to investigate the changing characteristics and influencing factors of measles antibodies in preterm infants (PT), and to provide scientific basis for optimizing MCV vaccination strategy of the target population. Blood samples were collected from PT and full-term infants (FT) at the chronological age (CA) of 3, 6, and 12 months. Measles antibodies were quantitatively detected by enzyme-linked immunosorbent assay. Demographic and vaccination information were both collected. Kruskal-Wallis rank sum test was used to compare the measles antibodies among different gestation age (GA) groups, and multiple linear regression was performed to identify the correlative factors for the antibodies. Measles antibodies of PT decreased significantly with age increasing before MCV vaccination. The positive rates of antibodies of PT were 10.80% and 3.30% at the age of 3 and 6 months, respectively ( p  < .001). At 12 months, the measles antibodies and seropositive rate in the infants who received MCV vaccination increased sharply ( p  < .001). Regression analyzes showed that the younger the GA or the older the age, the lower the antibodies at 3 months(p < .001，p = .018); while the lower measles antibody levels at 3 months and older age predicted the lower antibodies at 6 months(p < .001, p  = .029). PT were susceptible to measles due to the low level of maternally derived antibodies before MCV vaccination. More efforts should be considered to protect the vulnerable population during their early postnatal life.

Mumps is a vaccine-preventable disease caused by the mumps virus, but the incidence of mumps has increased among the children who were vaccinated with one-dose measles-mumps-rubella (MMR) in recent years. In this study, we analyzed the influence of different doses of mumps-containing vaccine (MuCV) against mumps using Cox-proportional hazard model. We collected 909 mumps cases of children who were born from 2006 to 2010 and vaccinated with different doses of MuCV in Quzhou during 2006-2018, which were all clinically diagnosed. Kaplan-Meier survival methods and Cox-proportional hazard model were used to estimate the hazard probabilities. Kaplan-Meier curves showed that the cumulative hazard of male and female has no difference; lower hazards were detected among those who were vaccinated with two-dose MuCV, born in 2006, and infected after supplementary immunization activities (SIA). Cox-proportional hazard regression suggested that onset after SIA, born in 2006, and vaccinated with two-dose MuCV were protective factors against infection even after adjusting for potential confounding effects. Our study showed that it was necessary to revise the diagnostic criteria of mumps and identify RT-PCR as the standard for mumps diagnosis in China. We suggested that routine immunization schedule should introduce two doses of MMR and prevaccination screening should be performed before booster immunization in vaccinated populations. [ABSTRACT FROM AUTHOR]

Rubella virus is the most teratogenic virus known to science and is capable of causing large epidemics. The RA 27/3 rubella vaccine, usually combined with measles vaccine, has eliminated rubella and congenital rubella syndrome from much of the world, notably from the Western Hemisphere. Except in immunosuppressed individuals, it is remarkably safe. Together with rubella vaccine strains used in China and Japan, eradication of the rubella virus is possible, indeed more feasible than eradication of measles or mumps. [ABSTRACT FROM AUTHOR]

Background: Measles outbreaks re-emerged in 2013–2014 in Guangxi Zhuang Autonomous Region of China, where measles immunisation coverage is high. The discrepancy between the vaccination coverage and outbreaks indicates that timeliness is crucial, yet there is limited knowledge on the health system barriers to timely vaccination. Using integrated evidence at the household, village clinic, and township hospital levels, this study aimed to identify the determinants of failure in receiving timely measles vaccinations among children in rural Guangxi. Methods: A multi-stage stratified cluster sampling survey with a nested qualitative study was conducted among children aged 18–54 months in Longan, Zhaoping, Wuxuan, and Longlin counties of Guangxi from June to August 2015. The status of timely vaccinations for the first dose of measles-containing vaccine (MCV1) and the second dose of measles-containing vaccine (MCV2) was verified via vaccination certificates. Data on household-level factors were collected using structured questionnaires, whereas data on village and township-level factors were obtained through in-depth interviews and focus group discussions. Determinants of untimely measles vaccinations were identified using multilevel logistic regression models. Results: A total of 1216 target children at the household level, 120 villages, and 20 township hospitals were sampled. Children were more likely to have untimely vaccination when their primary guardian had poor vaccination knowledge [MCV1, odds ratio (OR) = 1.72; MCV2, OR = 1.51], had weak confidence in vaccines (MCV1, OR = 1.28–4.58; MCV2, OR = 1.42–3.12), had few practices towards vaccination (MCV1, OR = 12.5; MCV2, OR = 3.70), or had low satisfaction with vaccination service (MCV1, OR = 2.04; MCV2, OR = 2.08). This trend was also observed in children whose village doctor was not involved in routine vaccination service (MCV1, OR = 1.85; MCV2, OR = 2.11) or whose township hospital did not provide vaccination notices (MCV1, OR = 1.64; MCV2, OR = 2.05), vaccination appointment services (MCV1, OR = 2.96; MCV2, OR = 2.74), sufficient and uniformly distributed sessions for routine vaccination (MCV1, OR = 1.28; MCV2, OR = 1.17; MCV1, OR = 2.08), or vaccination service on local market days (MCV1, OR = 2.48). Conclusions: Guardians with poor knowledge, weak beliefs, and little practice towards vaccination; non-involvement of village doctors in routine vaccinations; and inconvenient vaccination services in township hospitals may affect timely measles vaccinations among children in rural China. [ABSTRACT FROM AUTHOR]

We previously reported genotype D11 strains of measles virus that were first isolated from a measles outbreak associated with imported cases in Yunnan province of China by Zhang et al. (Emerg Infect Dis 16(6):943–7, 2010). Genotype D11 has been identified as the 24th genotype of the WHO reference strains. In this study, we sequenced the whole genome of a D11 strain. Phylogenetic analysis using the complete genome sequences of D11 and other reference strains showed that the D11 strain formed a distinct branch that was distant from the other genotypes and was most closely related to the reference strain D7. The M-F non-coding region (NCR) and the N450 coding region sequence (CDS) were found to be the most variable regions. This report provides basic genetic data on genotype D11 for further study of measles evolution and the support for measles elimination. [ABSTRACT FROM AUTHOR]

Measles is a highly infectious illness requiring herd immunity of 95% to interrupt transmission. China has not reached elimination goals despite high vaccination coverage. We estimated the population susceptibility against measles in Tianjin, China and to tailor awareness raising activities in the measles elimination plan. Age-specific measles seroprevalence was evaluated by Enzyme-Linked Immunosorbent Assay (ELISA) on 12,164 individual aged 0–44 years in 2009–2018. Measles IgG avidity testing was performed to confirm the relationship of the waning immunity after vaccination and secondary vaccination failures (SVF) on 324 confirmed measles cases in 2013–2018. 11,108 samples (91.32%) tested positive for measles IgG, 239 (1.96%) tested as equivocal and 817 (6.72%) were negative. The age distribution of measles cases in Tianjin followed a U-shaped curve and was highest for those at <8 months and again at 20–39 years which correlated closely with the age distribution of measles susceptibility based on measles IgG antibody status (r = 0.72, P < 0.001). The seropositivity rate and antibody geometric mean concentration (GMC) for the 2018 study population were significantly lower (χ 2 = 7.45, P = 0.006 and t = 12.01, P < 0.001) compared to 2009. The multivariate stepwise logistic regression analysis showed that age and region were the risk factors for both measles seropositivity rate and GMC after vaccination. The proportion of high avidity cases increased with age, being significantly higher in 75.31% of cases in patients aged 30–34 years (χ 2 = 18.04, P = 0.003). High immunization coverage in children alone will not be adequate to realizing sufficient levels of population herd immunity, particularly given that the potential susceptibility window in adult. Implementation of supplemental immunization activity (SIA) targeted to appropriate group aged 30–34 years is recommended. [ABSTRACT FROM AUTHOR]

Although global progress in measles control has been realized, achieving elimination has proven difficult in many regions of the world. China has adopted a goal of measles elimination but recent outbreaks predominantly affecting children <8 months who are ineligible for vaccination and incompletely protected by maternal antibodies has impeded progress. We assess the cost-effectiveness of adding an initial measles vaccine dose in China to earlier than the currently recommended 8 months of age. We conducted a cost-utility analysis comparing the costs and health benefits associated with adding a measles vaccine dose to the routine schedule at 4, 5, 6 or 7 months compared to the current recommendation for the first dose at age 8 months. A decision analytic model was developed in Microsoft Excel, including five non-severe and two fatal health outcomes associated with measles infection. Model parameters were informed by the literature and surveillance data. Future costs and health benefits were discounted at 3%. Primary outcomes included costs, Quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER) over a lifetime time horizon. Lowering the recommended age for initiating the measles vaccination series to address susceptibility in children <8 months provided incremental health gains compared to minimal costs at the individual-level. The ICER was most favorable ($232.70 per QALY gain) for administering an initial dose at 4 months of age due to fewer incremental program costs when shifting measles administration to an immunization visit already established under the Chinese vaccination program. We found potential beneficial health gains at a minimum cost associated with adding an earlier measles dose <8 months of age in China. Further investigation about disease transmission dynamics is required to more fully assess the tradeoffs of administering measles at a younger age to infants in China. [ABSTRACT FROM AUTHOR]

To block transmission of measles, the China Ministry of Health endorsed the "2006–2012 National Measles Elimination Action Plan (NMEAP)" on November 11, 2006, while no published studies used mathematical models to assess the impact of this action. Also, the problem of residuals autocorrelation due to auto-correlated infectious disease data is often ignored in practice. Based on monthly counts of measles in 31 Chinese provinces during 2004–2016, a spatiotemporal auto-correlated mixed model was developed to assess the intervention effects over 10 years after the NMEAP, after controlling for seasonality and time-varying socioeconomic and meteorological factors. The first-order autoregression dynamic relationship was used to adjust the bias of conditional covariance in Quasi-likelihood function due to temporal autocorrelation and the spatial autoregressive term was used to capture the neighbor effects of adjacent provinces. There were a similar seasonal pattern and spatial differences of measles incidence among provinces, yet the spatiotemporal pattern was diminished after the intervention. The introduction of the NMEAP was associated with a reduction of 51.03% [excess risk (ER%) = −51.03%, 95% CI: −62.32% to −36.37%] in measles morbidity on average during the 10-year intervention period. The intervention effect varied with time. The significant effect was observed 15 months after the intervention onset, and then gradually increased to a stable level, but was weakened slightly after 2012. The effect of birth rate and meteorological factors on measles morbidity reduced after the NMEAP. There was clear evidence that prominent progress towards a goal of measles elimination had been achieved after the intervention, while the resurgence after 2012 indicated the goal for measles elimination by 2012 had not been reached. [ABSTRACT FROM AUTHOR]

• The current measles immunization programs are effective in China. • The next focus groups of measles immunization activities in China was recommended. • MCV vaccination reduces the frequencies of clinical symptoms and complications. Measles incidence has decreased dramatically in China due to the implement of measles-containing vaccine (MCV). However, a measles epidemic caused resurgence recently, even among vaccinated individuals. To evaluate the effectiveness of current immunization programs and discuss initiatives for the next step in measles elimination in mainland China, the characteristics of 121,969 laboratory-confirmed measles cases reported in the measles surveillance system (MSS) during 2014–2018 were analyzed according to the vaccination status of the cases in this study. Children under 2 years of age without MCV vaccination (44,424, 36.42% of all cases) and adults over 20 years of age with an unknown vaccination history (37,564, 30.80% of all cases) accounted for the majority of measles cases from 2014 to 2018. 42,425 (34.78%) of the 77,384 cases with available vaccination information were categorized as programmatically preventable. 38,840 (91.55%) of the 42,425 cases were aged ≥8 months without the MCV vaccination history. 34,959 (28.66%) cases were categorized as programmatically non-preventable, of whom 22,611 (64.68%) were too young to receive their first MCV dose, 6857 (19.61%) received their first dose and were too young to receive their second dose, 5491 (15.71%) received at least two doses of MCV. 15,933 (13.06%) of the 121,969 cases had a history of MCV vaccination. Measles virus infection in cases with an MCV vaccination history mainly occurred within the first month after MCV vaccination, especially in those who received a one-dose measles vaccination. MCV vaccination could reduce the frequencies of clinical symptoms and complications of measles cases. Our study confirmed that the current measles immunization programs used in mainland China is effective in reducing the measles incidence in China. Unvaccinated infants/children aged 8–23 months and high risk susceptible adults over 20 years of age with unknown vaccination histories should be the focus groups of measles immunization activities in China in the future. [ABSTRACT FROM AUTHOR]

In mainland China, measles infection reached the lowest level in 2012 but resurged again after that with a seasonally fluctuating pattern. To investigate the phenomenon of periodic outbreak and identify the crucial parameters that play in the transmission dynamics of measles, we formulate a mathematical model incorporating periodic transmission rate and asymptomatic infection with waning immunity. We define the basic reproduction number as the threshold value to govern whether measles infection dies out or not. Fitting the reported measles cases from 2013 to 2016 to our proposed model, we estimate the basic reproduction number R0 with immunization to be 1.0077. From numerical simulations, we conclude asymptomatic infection does not cause much new infections and the key parameters affecting the transmission of measles are vaccination rate, transmission rate, and recovery rate, which suggests the public to enhance vaccination and protection measures to reduce effective contacts between susceptible and infective individuals and treat infected individuals timely. To minimize the number of infected individuals at a minimal cost, we formulate an optimal control system to design optimal control strategies. Numerical simulations show the effectiveness of optimal control strategies and recommend us to implement the control strategies as soon as possible. In particular, enhancing vaccination is especially effective in lowering the initial outbreak and making disease recurrence less likely. [ABSTRACT FROM AUTHOR]

Background: The incidence rate of measles in China reached a nadir in 2012 after 2 supplementary immunization activities (SIAs) were undertaken in 2009 and 2010. However, the disease began re-emerging in 2013, with a high prevalence rate observed in 2013-2014 in the southern province of Guangdong. In this study, we assessed the changes that occurred in measles epidemiology during 2009-2016, particularly between 2009 and 2011 (when the influence of the SIAs were in full effect) and between 2012 and 2016 (when this influence subsided).Methods: Data from 22,362 patients with measles diagnosed between 2009 and 2016, and whose diagnoses were confirmed clinically and/or with laboratory testing, were extracted from the National Infectious Disease Monitoring Information System. Descriptive analyses were performed, and changes in epidemiological characteristics between 2009 and 2011 and 2012-2016 were compared.Results: There was a substantial surge in 0-8-month-old patients after 2012; the incidence rate increased from 4.0 per 100,000 population in 2011 (10.3% of the total) to 280 per 100,000 population in 2013 (32.8% of the total). Patients aged 0-6 years represented 73.4% of the total increase between 2011 and 2013. Compared with 2009-2011, adults aged ≥25 years accounted for a higher proportion of patients in 2013 and after (p < 0.01), and were highest in 2016 (31% of the patient total).Conclusion: Despite the remarkable results achieved by SIAs in terms of providing herd immunity, the 2013 resurgence of measles revealed insufficient immunization coverage among children. Therefore routine immunization programs should be strengthened, and supplementary vaccinations targeting adults should also be contemplated. [ABSTRACT FROM AUTHOR]

Measles remains a public health concern in many regions, and the imported measles cases continue to challenge the measles elimination program for most of the countries where measles was verified to be eliminated or approaching elimination. The imported measles cases have been reported since October, 2017, in Jiangsu province, China. In this study, we reported the first imported B3 genotype measles virus from Egypt and the second imported D8 genotype measles virus from Philippines through international traveling. No secondary measles cases were found after these imported cases. Our findings highlighted the importance of measles vaccination targeting international travelers in China. [ABSTRACT FROM AUTHOR]

• We investigated whether infections in migrants were related to the epidemic resurgence of measles in 2013–2014. • Infections in migrants were not significantly associated with the resurgence in 2013–2014. • Instead, the resurgence was likely attributable to infants aged <8 months and the unvaccinated. • Officials are thus advised to give higher priority to appropriate populations when formulating control measures. The 2009 province-wide and 2010 nationwide supplementary immunization activities (SIAs) greatly reduced measles prevalence in Guangdong, a province in southern China with the largest migrant population. However, during 2013–2014, Guangdong experienced a resurgence of the measles epidemic. This study was performed to examine the association between infections in migrants and the resurgence of the measles epidemic. The records of 22 362 clinically and laboratory-confirmed measles cases from the years 2009 to 2014 were extracted from the National Infectious Disease Monitoring Information System. The epidemiological characteristics of infections in migrants during 2009–2012 were compared to those during 2013–2014. Infections in migrants were not significantly associated with the resurgence of the measles epidemic in 2013–2014 (p = 0.98). Nevertheless, for infections among locals and migrants during 2009–2012 and 2013–2014, substantial increases in the proportion of infection were detected among children aged <8 months and the unvaccinated population (p < 0.01). The study findings suggest that infections in migrants might not have been the major cause of the epidemic resurgence of measles. Instead, the resurgence was likely due to infections among children aged <8 months and the unvaccinated. Thus, officials are advised to give higher priority to appropriate populations when formulating control measures, and to strengthen routine surveillance of vaccination coverage among them. [ABSTRACT FROM AUTHOR]

To identify measles vaccine failures in Tianjin, China using a measles virus IgG avidity assay. The China Information System for Disease Control and Prevention (CISDCP) was used to collect information about measles cases and blood specimens in Tianjin from 2013 to 2015. Measles-specific IgM and IgG antibodies were detected using Enzyme-Linked Immunosorbent Assay (ELISA). Avidity testing for measles IgG was performed using a commercial enzyme immunoassay (EIA). A total of 284 confirmed measles cases were identified. Of this total, 262 (92.25%) were in patients aged ≥ 20 years. High avidity was exhibited in 172 (60.56%) cases, while 80 (28.17%) cases demonstrated low avidity. High avidity was detected in only 21.43% of cases in patients aged < 1 year. The proportion of high avidity increased with age, and was significantly higher in patients aged 30–39 years at 70.07% (χ 2 = 17.27, P = 0.002). Of the 52 measles cases in patients with a history of vaccinations, 41 (78.85%) cases showed high avidity, indicating secondary vaccine failures (SVF). In these vaccinations, there was no significant difference (P > 0.05) in clinical severity between high avidity and low avidity cases. However, regardless of vaccination status, clinical severity was significantly lower in high avidity cases (P < 0.001) than in low avidity cases. The percentages of positive measles IgM results in high avidity and low avidity cases were 66.28% and 91.25%, respectively. Geometric Mean Concentration (GMC) was significantly lower in high avidity cases at 33.73 U/mL, compared to 166.07 U/mL in low avidity cases. Low clinical severity and inconclusive IgM antibody results are more likely in high avidity measles cases. Measles cases were more common in adults. Therefore, a further dose of vaccines should be recommended for 30–39 years in Tianjin. [ABSTRACT FROM AUTHOR]

Background: Measles is among the most highly infectious human diseases. By virtue of increasingly effective childhood vaccination, together with targeted supplemental immunization activities (SIAs), health authorities in the People's Republic of China have reduced measles' reproduction number from about 18 to 2.3. Despite substantial residual susceptibility among young adults, more in some locales than others, sustained routine childhood immunization likely would eliminate measles eventually. To support global eradication efforts, as well as expedite morbidity and mortality reductions in China, we evaluated alternative SIAs via mechanistic mathematical modelling.Methods: Our model Chinese population is stratified by immune status (susceptible to measles infection; infected, but not yet infectious; infectious; and recovered or immunized), age (0, 1-4, 5-9, …, 65+ years) and location (31 provinces). Contacts between sub-populations are either empirical or a mixture of preferential and proportionate with respect to age and decline exponentially with distance between locations at age-dependent rates. We estimated initial conditions and most parameters from recent cross-sectional serological surveys, disease surveillance and demographic observations. Then we calculated the reproduction numbers and gradient of the effective number with respect to age- and location-specific immunization rates. We corroborated these analytical results by simulating adolescent and young adult SIAs using a version of our model in which the age-specific contact rates vary seasonally.Results: Whereas the gradient indicates that vaccinating young adults generally is the optimal strategy, simulations indicate that a catch-up campaign among susceptible adolescent schoolchildren would accelerate elimination, with timing dependent on uptake.Conclusions: These results are largely due to indirect effects (i.e. fewer infections than immunized people might otherwise cause), which meta-population models with realistic mixing are uniquely capable of reproducing accurately. [ABSTRACT FROM AUTHOR]

Plant of peperomia dindygulensis Miq. is widely distributed in southern regions of China, which is traditionally used to treat cough, measles, abscesses and cancerous swelling in Chinese folk. As a traditional medicinal agent, a wide spectrum of chemical constituents have been isolated from the P. dindygulensis, including lignans, flavonoids, flavone glycosides, polyketides and other compounds. The research shows that these compounds exhibited bioactivities including antitumor and antiangiogenesis. Hence, this report is presented as a review centered on the chemical constituents and pharmacological activities of the P. dindygulensis, aiming at its further development and potential value. [ABSTRACT FROM AUTHOR]

• 1st adequacy evaluation of measles laboratory diagnostic tests in mainland China. • National diagnostic criteria would lead to missed measles diagnosis. • MCV immunization history lowered sensitivity of IgM tests and RT-PCR. • IgM test and RT-PCR should be combined for vaccinated cases and cases aged ≥15y. Measles-containing vaccine (MCV) was introduced in 1965 in Beijing and given to the children aged 8m–14y. In population-based surveillance system, real-time polymerase chain reaction (RT-PCR) and immunoglobulin M(IgM) serology tests have been conducted for each suspected case since 2013. We used the surveillance data to evaluate the adequacy of the tests for laboratory confirmation during 2014–2016. Informations on IgM tests, RT-PCR, age, vaccination history for confirmed cases were from the surveillance system. Laboratory confirmed cases were defined as cases with positive IgM serology and/or positive RT-PCR. All tests were conducted in the laboratories accredited by Beijing CDC or Beijing CDC laboratory. Totally 4600 cases were confirmed. Sensitivities of IgM tests within 0–3 days post rash, IgM tests within 4–28 days post rash and RT-PCR within 0–3 days post rash were 56.53%, 82.06% and 94.39%, respectively. The combined sensitivity of IgM tests and RT-PCR decreased by the interval between rash onset and collection of virologic specimen. MCV immunization history lowered sensitivity of IgM tests and RT-PCR. Among the cases aged ≥ 15 years, around 95% had no written immunization records. The sensitivity of IgM tests within 0–3 days post rash was less than 60%. Around 60% had unknown immunization histories. Compared with unvaccinated cases based on written records, unvaccinated cases based on recollection had no significantly different sensitivity of laboratory tests. But unknown immunization history significantly lowered sensitivity of RT-PCR within 0–3 days post rash. Neither IgM tests nor RT-PCR reached 100% sensitive for confirmed cases. Virologic specimen should be collected as early as possible to achieve maxim sensitivity. Cases with unknown immunization history could not be treated as unvaccinated. Combination of the two tests and further laboratory assays were needed especially for vaccinated cases or cases aged ≥15 years. [ABSTRACT FROM AUTHOR]

Due to the Expanded Program on Immunization (EPI) and supplementary immunization activities (SIAs) in China, the incidence of measles in China has decreased extensively. The incidence reached its lowest levels in contemporary history in 2012 and 2017, with incidence rates of 4.6 and 4.3 per million population, respectively. However, more than 147,000 measles cases were reported from 2013 to 2016. Furthermore, the proportions of cases in infants < 8 months and adults have been increasing since 2013, representing a considerable challenge for measles elimination in China. A total of 14,868 measles viruses were isolated from confirmed measles cases from 2011 to 2017, of which 14,631 were identified as the predominant endemic genotype, H1; 87 were identified as genotype A viruses that were vaccine associated strains; and 150 were identified as non-H1 genotype viruses. The non-H1 genotype viruses included 62 D8 viruses, 70 D9 viruses, 3 D11 viruses, 14 B3 viruses, and 1 G3 virus, which were identified as imported or import-related viruses that caused sporadic cases or small outbreaks. Most of the transmission chains detected during the period 2011–2012 were interrupted and were followed by many new transmission chains of unknown origin that spread, causing a large measles resurgence in China during 2013–2016. After 4 years of measles resurgence and continuous implementation of the routine immunization program and SIAs, the population immunity reached a sufficiently high level to interrupt most of the transmission chains; only a few strains survived, which continued to be sporadically detected in China in 2017. In the present study, the results from the combined epidemiological and molecular virological data demonstrated the great progress towards measles elimination in China by the further analysis of circulation dynamics for the endemic H1 genotype measles virus from 2011 to 2017. And this study accumulated critical baseline data on circulating wild-type measles viruses in China and provides comprehensive information to the world. These comprehensive baseline data provide evidence to support measles elimination in the future, not only in China but also in other countries worldwide. In addition, the information will be very useful to other countries for tracing their sources of measles cases and for identifying transmission links, which can help prevent potential measles outbreaks. [ABSTRACT FROM AUTHOR]

• Measles cases among children in Tianjin still occur in those who have been vaccinated. • 29% of measles surveillance system cases with known vaccine history were vaccinated. • In a Case Series from 2011 to 2015, 54% of measles cases had been vaccinated. • Incremental doses of measles vaccine increased the time-to-disease onset. • More research is needed to understand the reasons for vaccine failure. Despite increasing global measles vaccination coverage, progress toward measles elimination has slowed in recent years. In China, children receive a measles-containing vaccine (MCV) at 8 months, 18–24 months, and some urban areas offer a third dose at age 4–6 years. However, substantial measles cases in Tianjin, China, occur among individuals who have received multiple MCV doses. This study describes the vaccination history of measles cases 8 months – 19 years old. Data came from measles cases in Tianjin's reportable disease surveillance system (2009–2013), and from a case control study (2011–2015). Twenty-nine percent of those in the surveillance dataset and 54.4% of those in the case series received at least one dose of MCV. The minimum and median time-to-diagnosis since vaccination revealed an increase in time since vaccination for incremental doses. Considerable measles cases in Tianjin occur in vaccinated children, and further research is needed to understand the reasons for vaccine failure. [ABSTRACT FROM AUTHOR]

To evaluate the economic impact of the current measles vaccination program in Zhejiang Province, east China. A decision tree-Markov model with parameters from published literatures, government documents and surveys was developed and used to simulate over 40 years of a birth cohort in Zhejiang Province during the year 2014. The expected cost and effectiveness of the current measles vaccination program was compared against no vaccination. Costs were assessed from the payer's perspective. Benefits were defined as savings on the direct cost of measles treatment, and the effectiveness was measured according to the number of measles cases and deaths averted. The net present value (NPV), benefit-cost ratio (BCR) and incremental cost-effectiveness ratio (ICER) were also calculated. A threshold for cost-effectiveness of less than 3 times the Gross Domestic Product (GDP) per capita was used. One-way sensitivity analysis was performed to assess parameter uncertainties. The total vaccination cost was estimated to be $2.52 million. The BCR of the current measles program was found to be 6.06 with a NPV of $73.38 million. It was also calculated that a total of 195,165 measles cases and 191 measles-related deaths would be prevented by vaccination. The ICER was approximately $12.91 per case averted and $13,213.43 per death averted, respectively, which was cost-effective. The models were proven to be robust. The current measles vaccination program appeared to be cost-effective and to offer substantial benefits. The results of this analysis sought to contribute to the justification of future investments to achieve the goal of measles elimination. [ABSTRACT FROM AUTHOR]

The target of eliminating measles has not been achieved, and measles has resurged in Zhejiang, China, since 2013. In this study, we hypothesized that population density and the proportion of the floating population were the potential causes of measles persistence in Zhejiang. Measles cases in Zhejiang from 2004 through 2017 were analyzed using data from the National Notifiable Diseases Reporting System (NNDRS). Reported measles incidence and annual incidence by age were described. Spearman correlation coefficients were used to assess correlations between measles incidence and population density and the proportion of floating population. A total of 48,648 measles cases were reported during the 14-year period. Two large measles epidemics occurred in 2005 (14,317 cases, incidence of 29.38/100,000) and 2008 (12,782 cases, incidence of 25.26/100,000). A higher proportion of cases occurred in young adults aged 20 to 34 years and infants under 1 year of age. A positive correlation was observed between measles incidence and either population density or proportion of inter-provincial floating populations. In general, Zhejiang suffers from a high incidence of measles partly because of its high population density and the low vaccination rates among inter-provincial floating populations. To meet the target of measles elimination, convincing susceptible young adults and migrant children to get vaccinated remains a critical issue. The target of eliminating measles has not been achieved, and measles has resurged in Zhejiang, China, since 2013. In this study, the authors hypothesized that population density and the proportion of the floating population were potential causes of measles persistence in Zhejiang. They found that Zhejiang suffers from a high incidence of measles partly because of the low vaccination rates among inter-provincial floating populations. [ABSTRACT FROM AUTHOR]

Measles is a highly infectious, severe viral disease. The disease is targeted for global eradication; however, this result has proven challenging. In China, where countrywide vaccination coverage for the last decade has been above 95% (the threshold for measles elimination), measles continues to cause large epidemics. To diagnose factors contributing to the persistency of measles, here we develop a model-inference system to infer measles transmission dynamics in China. The model-inference system uses demographic and vaccination data for each year as model inputs to directly account for changing population dynamics (including births, deaths, migrations, and vaccination). In addition, it simultaneously estimates unobserved model variables and parameters based on incidence data. When fitted to yearly incidence data for the entire population, it is able to accurately estimate independent, out-of-sample age-specific incidence. Using this validated model-inference system, we are thus able to estimate epidemiological and demographical characteristics key to measles transmission during 1951–2004 for three key locations in China, including its capital Beijing. These characteristics include age-specific population susceptibility and incidence rates, the basic reproductive number (R0), reporting rate, population mixing intensity, and amplitude of seasonality. Key differences among the three sites reveal population and epidemiological characteristics crucial for understanding the current persistence of measles epidemics in China. We also discuss the implications our findings have for future elimination strategies. [ABSTRACT FROM AUTHOR]

Highlights • We investigated a measles outbreak in health workers in a Chinese medical hospital, Beijing, China. • Most cases had no documented measles-containing vaccination before the outbreak. • High-level post-exposure measles vaccination contributed largely to contain the outbreak and might provide an indirect protection for inpatients. • 2-Dose measles-containing vaccination of susceptible health workers is warranted in China. Abstract Background Since the National Action Plan for Measles Elimination 2006–2012 was released in 2006, China has entered into an era of accelerated measles elimination. Despite substantial decline, measles outbreak continued to occur mainly in a non-targeted population, in particular health workers due to occupational exposure. We investigated a measles outbreak in a Chinese medicine hospital, Beijing, in March 2018. Methods Descriptive analysis was performed on epidemiology of the outbreak, clinical and laboratory evaluations, vaccination status of cases, and public health response. A case-control study was also conducted to identify the associated risk factors for measles. Results From March 13, 2018, through March 27, 2018, a total of 11 measles cases in health workers were reported in Hospital X, Beijing. The median age of cases was 26 years (range, 21–53) and 4 (36.4%) were male. Of the 11 cases, ten had not been vaccinated or had unknown vaccination status; two occurred in emergency departments. No inpatients became infected, 141 (83.9%) of whom in affected departments were 55 years of age or older. The outbreak was confirmed by laboratory testing; the virus strain was genotype H1. The response activities included isolation of cases, and enhanced health surveillance of health workers and inpatients, particularly in affected departments. A total of 2234 doses of measles-containing vaccines (MCVs) were administered, covering 93.3% of susceptible health workers, in addition to 973 doses to the susceptible individuals in household and community. Lack of documentation of MCV vaccination before the outbreak was identified as a risk factor for measles (odd ratio: 3.333, 95% confidence interval: 1.295–8.621). Conclusions High coverage of outbreak response immunization activities contributed largely to limit the spread of measles and might provide an indirect protection for inpatients. 2-Dose measles-containing vaccination of personnel in healthcare settings is warranted to prevent potential nosocomial transmission of measles. [ABSTRACT FROM AUTHOR]

Measles, a highly contagious infection caused by the measles virus, is a major public health problem in China. The reported measles cases decreased dramatically from 2004 to 2012 due to the mandatory measles vaccine program started in 2005 and the goal of eliminating measles by 2012. However, after reaching its lowest level in 2012, measles has resurged again since 2013. Since the monthly data of measles cases exhibit a seasonally fluctuating pattern, based on the measles model in Earn et al. (Science 287:667-670, 2000), we propose a susceptible, exposed, infectious, and recovered model with periodic transmission rate to investigate the seasonal measles epidemics and the effect of vaccination. We calculate the basic reproduction number R0, analyze the dynamical behavior of the model, and use the model to simulate the monthly data of measles cases reported in China. We also carry out some sensitivity analysis of R0 in the terms of various model parameters which shows that measles can be controlled and eventually eradicated by increasing the immunization rate, improving the effective vaccine management, and enhancing the awareness of people about measles. [ABSTRACT FROM AUTHOR]

Background: China is the largest developing country with a relatively developed public health system. To further prevent and eliminate the spread of infectious diseases, China has listed 39 notifiable infectious diseases characterized by wide prevalence or great harm, and classified them into classes A, B, and C, with severity decreasing across classes. Class A diseases have been almost eradicated in China, thus making class B diseases a priority in infectious disease prevention and control. In this retrospective study, we analyze the spatial distribution patterns of 12 class B notifiable infectious diseases that remain active all over China. Methods: Global and local Moran’s I and corresponding graphic tools are adopted to explore and visualize the global and local spatial distribution of the incidence of the selected epidemics, respectively. Inter-correlations of clustering patterns of each pair of diseases and a cumulative summary of the high/low cluster frequency of the provincial units are also provided by means of figures and maps. Results: Of the 12 most commonly notifiable class B infectious diseases, viral hepatitis and tuberculosis show high incidence rates and account for more than half of the reported cases. Almost all the diseases, except pertussis, exhibit positive spatial autocorrelation at the provincial level. All diseases feature varying spatial concentrations. Nevertheless, associations exist between spatial distribution patterns, with some provincial units displaying the same type of cluster features for two or more infectious diseases. Overall, high–low (unit with high incidence surrounded by units with high incidence, the same below) and high–high spatial cluster areas tend to be prevalent in the provincial units located in western and southwest China, whereas low–low and low–high spatial cluster areas abound in provincial units in north and east China. Conclusion: Despite the various distribution patterns of 12 class B notifiable infectious diseases, certain similarities between their spatial distributions are present. Substantial evidence is available to support disease-specific, location-specific, and disease-combined interventions. Regarding provinces that show high–high/high–low patterns of multiple diseases, comprehensive interventions targeting different diseases should be established. As to the adjacent provincial units revealing similar patterns, coordinated actions need to be taken across borders. [ABSTRACT FROM AUTHOR]

Background: Many measles cases in Tianjin, China, occur in infants whose mothers were born after widespread vaccination programs. We assessed age-specific decreases in maternal measles antibodies in infants and examined maternal and infant characteristics in relation to infant antibody titers.Methods: Infant and mother dyads were enrolled from a sample of immunization clinics in all Tianjin districts. Participants' antibody titers were measured from dried blood spots. A multivariable log-linear model regressed infant antibody titers onto infant and mother characteristics.Results: Among 551 infants aged ≤8 months, protective levels of measles antibodies were observed in infants whose mothers had measles titers ≥800 IU/mL (mean antibody titer, 542.5 IU/mL) or 400 to <800 IU/mL (mean, 202.2 IU/mL). Compared with infants whose mothers had no history of disease or vaccination, those with a history of disease had 1.60 times higher titers (95% confidence interval, 1.06-2.43).Conclusions: Limited vaccination programs in the 1980s have resulted in many Chinese women with inadequate protection against measles and an accordingly low efficiency of transplacental transmission to a fetus. Current vaccination programs, which target children aged 8 months through adolescence may be ineffective in controlling transmission of measles to infants. [ABSTRACT FROM AUTHOR]

Objectives: Infants aged <8 months are ineligible for measles vaccination in China but represent a disproportionate number of cases. We examined the risk factors for measles among infants in Tianjin, China. Study design: Case-control study. Methods: Cases were enrolled from a surveillance system, and IgG-negative controls were sampled from registries at immunization clinics. A logistic regression model assessed for risk factors. Results: Among 82 cases and 485 controls, exposure to a municipal hospital (OR [odds ratio]: 5.21; 95% confidence interval [CI]: 1.19-22.82) or a specialty hospital (OR: 13.22; 95% CI: 6.13-28.51) was associated with the disease, whereas visiting a township or district hospitals was not associated with increased odds of measles. Conclusions: Hospitals were an important focal point of measles transmission for infants. Hospitals, particularly higher-level municipal and specialty hospitals, should enforce infection control programs to separate infants with highly communicable diseases to prevent transmission. [ABSTRACT FROM AUTHOR]

Background China's rapid economic development has resulted in severe particulate matter (PM) air pollution and the control and prevention of infectious disease is an ongoing priority. This study examined the relationships between short-term exposure to ambient particles with aerodynamic diameter ≤2.5 µm (PM 2.5 ) and measles incidence in China. Methods Data on daily numbers of new measles cases and concentrations of ambient PM 2.5 were collected from 21 cities in China during Oct 2013 and Dec 2014. Poisson regression was used to examine city-specific associations of PM 2.5 and measles, with a constrained distributed lag model, after adjusting for seasonality, day of the week, and weather conditions. Then, the effects at the national scale were pooled with a random-effect meta-analysis. Results A 10 µg/m 3 increase in PM 2.5 at lag 1 day, lag 2 day and lag 3 day was significantly associated with increased measles incidence [relative risk (RR) and 95% confidence interval (CI) were 1.010 (1.003, 1.018), 1.010 (1.003, 1.016) and 1.006 (1.000, 1.012), respectively]. The cumulative relative risk of measles associated with PM 2.5 at lag 1–3 days was 1.029 (95% CI: 1.010, 1.048). Stratified analyses by meteorological factors showed that the PM 2.5 and measles associations were stronger on days with high temperature, low humidity, and high wind speed. Conclusions We provide new evidence that measles incidence is associated with exposure to ambient PM 2.5 in China. Effective policies to reduce air pollution may also reduce measles incidence. [ABSTRACT FROM AUTHOR]

Background: In China, the measles vaccine is offered for free whereas the pneumococcal vaccine is a for-fee vaccine. This difference has the potential to influence how caregivers evaluate whether a vaccine is important or necessary for their child, but it is unclear if models of health behavior, such as the Health Belief Model, reveal the same associations for different diseases. This study compares caregiver perceptions of different diseases (measles, pneumonia and meningitis); and characterizes associations between Health Belief Model constructs and both pneumococcal vaccine uptake and perceived vaccine necessity for pneumonia, measles, and meningitis.Methods: Caregivers of infants and young children between 8 months and 7 years of age from Shanghai (n = 619) completed a written survey on their perceptions of measles, pneumonia, and meningitis. We used logistic regression models to assess predictors of pneumococcal vaccine uptake and vaccine necessity.Results: Only 25.2% of children had received a pneumococcal vaccine, although most caregivers believed that pneumonia (80.8%) and meningitis (92.4%), as well as measles (93.2%), vaccines were serious enough to warrant a vaccine. Perceived safety was strongly associated with both pneumococcal vaccine uptake and perceived vaccine necessity, and non-locals had 1.70 times higher odds of pneumonia vaccine necessity than non-locals (95% CI: 1.01, 2.88).Conclusions: Most factors had a similar relationship with vaccine necessity, regardless of disease, indicating a common mechanism for how Chinese caregivers decided which vaccines are necessary. Because more caregivers believed meningitis needed a vaccine than pneumonia, health care workers should emphasize pneumococcal vaccination's ability to protect against meningitis. [ABSTRACT FROM AUTHOR]

The measles epidemic was rather severe in Wujin 2015, and a seroprevalence survey of measles antibody was conducted during June to September 2015 in Wjin district of Changzhou city. Blood samples were collected from community health population and convenient samples of residual blood from hospitals. Measles-specific IgG levels were measured by ELISA assay. A total of 122 measles cases were reported 2015 in Wujin district with an incidence of 8.31 per 100 000 populations. A large proportion of measles cases were adults ≥20 years (62.30%) and infants aged <18 months (28.69%). Floating population accounted for 68.57% of all cases. 1070 blood samples aged from 9 months to 49 years old were collected and the overall seroprevalence and geometric mean titer (GMT) of measles were 82.71% and 551.19 mIU/ml, respectively. Although the seroprevalence among children aged 9 months to 4 years was consistently over 90%, it began to decrease since 24 months, and till the age of ≥10 years, the seroprevalences were all <80%, however, the seroprevalence rised to above 80% in people over 40 years. There were no significant differences between the two blood sample sources in the level of seroprevalence and GMT. Also no significant differences were observed in the seroprevalence of measles and GMT levels between genders. The seroprevalence and GMT in people with measles vaccination were higher than those without measles vaccination or people whose measles vaccination are unknown (P < 0.001). Our study indicated that the adult measles cases have become a serious problem in Wujin district, which may mainly relate to the increasing size of the floating population with low measles vaccine coverage. The seroprevalence of measles decreased dramatically with increasing age since teenagers, which may mainly caused by waning vaccine-induced immunity. Therefore, it is necessary to strengthen measles vaccine in these people especially floating population. [ABSTRACT FROM AUTHOR]

Dust events affect human health in both drylands and downwind environments. In this study, we used county-level data during the period of 1965–2005 to assess the impact of dust events on measles incidence in Gansu province in Western China. We used Fast Fourier Transform (FFT) to set up the cyclical regression model; in particular, we set the model to downwind direction for the typical cities in the Hexi Corridor as well as the capital city Lanzhou. The results showed that Spring measles incidence was the highest in the Hexi Corridor, where dust events occur the most frequently over Gansu province. Measles incidence declined on the pathway of dust storms from west to east due to the weakening of both intensity and duration in dust storms. Measles incidence was positively correlated with monthly wind speed and negatively correlated with rainfall amount, relative humidity, and air pressure. Measles incidence was significantly ( p ≤ 0.01) positively correlated with daily coarse particles, e.g., TSP and PM 10 . According to the cyclical regression model, average monthly excess measles that is related to dust events was 39.1 (ranging from 17.3 to 87.6), 149.9 (ranging from 7.1 to 413.4), and 31.3 (ranging from 20.6 to 63.5) in Zhangye, Lanzhou, and Jiuquan, respectively. [ABSTRACT FROM AUTHOR]

Laboratory networks are an essential component of disease surveillance systems because they provide accurate and timely confirmation of infection. WHO coordinates global laboratory surveillance of vaccine preventable diseases, including measles and rubella. The more than 700 laboratories within the WHO Global Measles and Rubella Laboratory Network (GMRLN) supports surveillance for measles, rubella and congenial rubella syndrome in 191 counties. This paper describes the overall structure and function of the GMRLN and highlights the largest of the national laboratory networks, the China Measles and Rubella Laboratory Network. [ABSTRACT FROM AUTHOR]

Background: Outbreaks of measles re-emerged in Guangxi province during 2013-2014, where measles again became a major public health concern. A better understanding of the patterns of measles cases would help in identifying high-risk areas and periods for optimizing preventive strategies, yet these patterns remain largely unknown. Thus, this study aimed to determine the patterns of measles clusters in space, time and space-time at the county level over the period 2004-2014 in Guangxi.Methods: Annual data on measles cases and population sizes for each county were obtained from Guangxi CDC and Guangxi Bureau of Statistics, respectively. Epidemic curves and Kulldorff's temporal scan statistics were used to identify seasonal peaks and high-risk periods. Tango's flexible scan statistics were implemented to determine irregular spatial clusters. Spatio-temporal clusters in elliptical cylinder shapes were detected by Kulldorff's scan statistics. Population attributable risk percent (PAR%) of children aged ≤24 months was used to identify regions with a heavy burden of measles.Results: Seasonal peaks occurred between April and June, and a temporal measles cluster was detected in 2014. Spatial clusters were identified in West, Southwest and North Central Guangxi. Three phases of spatio-temporal clusters with high relative risk were detected: Central Guangxi during 2004-2005, Midwest Guangxi in 2007, and West and Southwest Guangxi during 2013-2014. Regions with high PAR% were mainly clustered in West, Southwest, North and Central Guangxi.Conclusions: A temporal uptrend of measles incidence existed in Guangxi between 2010 and 2014, while downtrend during 2004-2009. The hotspots shifted from Central to West and Southwest Guangxi, regions overburdened with measles. Thus, intensifying surveillance of timeliness and completeness of routine vaccination and implementing supplementary immunization activities for measles should prioritized in these regions. [ABSTRACT FROM AUTHOR]

Measles is a highly contagious and severe disease. Despite mass vaccination, it remains a leading cause of death in children in developing regions, killing 114,900 globally in 2014. In 2006, China committed to eliminating measles by 2012; to this end, the country enhanced its mandatory vaccination programs and achieved vaccination rates reported above 95% by 2008. However, in spite of these efforts, during the last 3 years (2013–2015) China documented 27,695, 52,656, and 42,874 confirmed measles cases. How measles manages to spread in China—the world’s largest population—in the mass vaccination era remains poorly understood. To address this conundrum and provide insights for future public health efforts, we analyze the geospatial pattern of measles transmission across China during 2005–2014. We map measles incidence and incidence rates for each of the 344 cities in mainland China, identify the key socioeconomic and demographic features associated with high disease burden, and identify transmission clusters based on the synchrony of outbreak cycles. Using hierarchical cluster analysis, we identify 21 epidemic clusters, of which 12 were cross-regional. The cross-regional clusters included more underdeveloped cities with large numbers of emigrants than would be expected by chance (p = 0.011; bootstrap sampling), indicating that cities in these clusters were likely linked by internal worker migration in response to uneven economic development. In contrast, cities in regional clusters were more likely to have high rates of minorities and high natural growth rates than would be expected by chance (p = 0.074; bootstrap sampling). Our findings suggest that multiple highly connected foci of measles transmission coexist in China and that migrant workers likely facilitate the transmission of measles across regions. This complex connection renders eradication of measles challenging in China despite its high overall vaccination coverage. Future immunization programs should therefore target these transmission foci simultaneously. [ABSTRACT FROM AUTHOR]

Background: Industrialization and demographic transition generate nonstationary dynamics in human populations that can affect the transmission and persistence of infectious diseases. Decades of increasing vaccination and development have led to dramatic declines in the global burden of measles, but the virus remains persistent in much of the world. Here we show that a combination of demographic transition, as a result of declining birth rates, and reduced measles prevalence, due to improved vaccination, has shifted the age distribution of susceptibility to measles throughout China.Methods and Findings: We fit a novel time-varying catalytic model to three decades of age-specific measles case reporting in six provinces in China to quantify the change in the age-specific force of infection for measles virus over time. We further quantified the impact of supplemental vaccination campaigns on the reduction of susceptible individuals. The force of infection of measles has declined dramatically (90%-97% reduction in transmission rate) in three industrialized eastern provinces during the last decade, driving a concomitant increase in both the relative proportion and absolute number of adult cases, while three central and western provinces exhibited dynamics consistent with endemic persistence (24%-73% reduction in transmission rate). The reduction in susceptible individuals due to supplemental vaccination campaigns is frequently below the nominal campaign coverage, likely because campaigns necessarily vaccinate those who may already be immune. The impact of these campaigns has significantly improved over time: campaigns prior to 2005 were estimated to have achieved less than 50% reductions in the proportion susceptible in the target age classes, but campaigns from 2005 onwards reduced the susceptible proportion by 32%-87%. A limitation of this study is that it relies on case surveillance, and thus inference may be biased by age-specific variation in measles reporting.Conclusions: The age distribution of measles cases changes in response to both demographic and vaccination processes. Combining both processes in a novel catalytic model, we illustrate that age-specific incidence patterns reveal regional differences in the progress to measles elimination and the impact of vaccination controls in China. The shift in the age distribution of measles susceptibility in response to demographic and vaccination processes emphasizes the importance of progressive control strategies and measures to evaluate program success that anticipate and react to this transition in observed incidence. [ABSTRACT FROM AUTHOR]

Objectives: The validity of parent-reported measles-containing vaccination history in children with measles has not been assessed. This study evaluated the accuracy of parental recall of measles-containing vaccination histories in Shenzhen, China. Study design: A retrospective study was performed to compare the data from the electronic records with parental recall. The electronic records were regarded as accurate data about the children's measles-containing vaccination status. Methods: We collected data from the National Notifiable Diseases Surveillance System and the Immunization Program Information Management System in Shenzhen city, China. Between 2009 and 2014, there were 163 children with measles who had electronic vaccination records; the vaccination status of these cases was reported by the parents in the field epidemiological investigation. We validated parental recall with electronic records. Results: The agreement between parental recall and electronic records was 78.7%. The kappa value was 0.57. The parent-reported measles-containing vaccination rate was higher than the electronic record (48.5% vs 41.7%, χ2 = 53.64, P < 0.001). The true positive rate for parental recall was 82.4%, and the true negative rate was 75.8%. The positive predictive value was 70.9%, and the negative predictive value was 76.6%. Conclusions: In children with measles, parental recall slightly overestimated the measles vaccination rate, and the vaccination status recalled by parents was in moderate agreement with the electronic record. [ABSTRACT FROM AUTHOR]

Introduction Following implementation of China's 2006–2012 Action Plan for measles elimination, which led to a nadir of measles in 2012, a resurgence started in 2013 that continued into 2014. Measles typically is a disease that mainly affects children. We investigated a community outbreak in 2014 with measles virus transmission among adults without children serving as virus reservoirs. Our investigation highlights adult susceptibility to measles. Methods We conducted a retrospective active case search, and analyzed confirmed case data to describe person, place, and time characteristics of the outbreak. All individuals with measles with onset during the first 2 months of the outbreak were interviewed face-to-face to determine source(s) of infection and transmission route (from whom and to whom). Results Among the 280 cases, 220 (77.6%) were among ≥20-year-old adults, 24 (8.6%) were among 8–23 month olds, 22 (7.9%) were among <8-month-old infants, and the remaining 14 (5.9%) were among 2–19 year olds. Of the 83 cases in the early stage of the outbreak, 41 (49.4%) were acquired in the community, 24 (28.9%) were acquired nosocomially, 13 (15.7%) were acquired by family contact, and 5 were imported. Among 44 clearly determined transmission linkages, 37 (84.1%) were adult to other age-group (these include 29 adult-to-adult, seven adult-to-child, and one adult-to-infant), six were from infants to adult and children, and one was child-to-child. Outbreak response immunization activities were implemented by non-selective supplementary immunization activities, with 51.3% of targeted 5–19-year-old children and adolescents, and 30.2% of targeted 20–49-year-old adults being vaccinated. Conclusions Despite high population immunity among children and adolescents following three rounds of measles vaccine supplementary immunization activities, sustained measles virus transmission still occurred among adults in this community. Adult measles immunity gaps might threaten measles elimination, highlighting the importance targeting susceptible adults during outbreak response immunization. [ABSTRACT FROM AUTHOR]

Introduction Endemic measles persists in China, despite >95% reported coverage of two measles-containing vaccine doses and nationwide campaign that vaccinated more than 100 million children in 2010. We performed a case–control study in six Chinese provinces during January 2012 through June 2013 to identify risk factors for measles infection among children aged 0–7 months. Methods Children with laboratory-confirmed measles were neighborhood matched with three controls. We interviewed parents of case and control infants on potential risk factors for measles. Adjusted matched odds ratios (mOR) and 95% confidence intervals (CIs) were calculated by multivariable conditional logistic modeling. We calculated attributable fractions for risk factors that could be interpreted as causal. Results Eight hundred thirty cases and 2303 controls were enrolled. In multivariable analysis, male sex (mOR 1.6 [1.3, 2.0]), age 5–7 months (mOR 3.9 [3.0, 5.1]), migration between counties (mOR 2.3 [1.6, 3.4]), outpatient hospital visits (mOR 9.4 [6.6, 13.3]) and inpatient hospitalization (mOR 107.1 [48.8, 235.1]) were significant risk factors. The calculated attributable fractions for hospital visits was 43.1% (95% CI: 40.1, 47.5%) adjusted for age, sex and migration. Conclusions Hospital visitation was the largest risk factor for measles infection in infants. Improved hospital infection control practices would accelerate measles elimination in China. [ABSTRACT FROM AUTHOR]

Introduction Endemic measles persists in China, despite >95% reported coverage of two measles-containing vaccine doses and nationwide campaign that vaccinated more than 100 million children in 2010. In 2011, almost half of the 9943 measles cases in China occurred in children eligible for measles vaccination. We conducted a case-control study during 2012–2013 to identify risk factors for measles infection in children aged 8 months–14 years. Methods Children with laboratory-confirmed measles were age- and neighborhood-matched with three controls. We interviewed parents of case and control infants on potential risk factors for measles. We calculated adjusted matched odds ratios and 95% confidence intervals of risk factors. We calculated attributable fractions for risk factors that could be interpreted as causal and vaccine efficacy (VE) for the measles containing vaccine (MCV) used in the Chinese immunization program. Results In all, 969 case-patients and 2845 controls were enrolled. In multivariable analysis, lack of measles vaccination both overall (mOR 22.7 [16.6, 31.1] and when stratified by region (east region, mOR 74.2 [27.3, 202]; central/western regions mOR 17.4 [12.5, 24.3]), hospital exposure (mOR 63.0, 95% CI [32.8, 121]), and migration among counties (overall mOR 3.0 [2.3, 3.9]) were significant risk factors. The calculated VE was 91.9–96.1% for a single dose of MCV and 96.6–99.5% for 2 doses. Conclusions Lack of vaccination was the leading risk factor for measles infection, especially in children born since the 2010 supplementary immunization activity. Reducing missed vaccination opportunities, improving immunization access for migrant children, and strengthening school/kindergarten vaccine checks are needed to strengthen the routine immunization program and maintain progress toward measles elimination in China. [ABSTRACT FROM AUTHOR]