Publications by authors named "Zhaodan Sun"

Objective: To evaluate the safety of primary immunization using CoronaVac® among population aged 3 years and above in a large-scale use.

Method: A multi-center open-label study was carried out in 11 provinces of China. Individuals aged 3 years and older who had no history of COVID-19 vaccination or had received only one dose of CoronaVac® were enrolled in this study.

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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.

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Background: To provide a better understanding of the progress on rubella control and elimination in China, a genetic analysis was conducted to examine the transmission pattern of the endemic rubella virus in China during 2010-2019.

Methods: A total of 4895 strains were obtained from 29 of the 31 provinces in mainland China during 2010-2019. The genotyping regions of the strains were amplified, determined, and assembled.

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By monitoring the sewage system in Heilongjiang province from 2013 to 2016, this study aimed to analyze the epidemiological tendency and genetic mutation of poliovirus (PV) found in the environment in order to setup a warning system for vaccine-derived poliovirus (VDPV) and the spread of wild poliovirus. In this study, we collected 139 sewage samples from 8 regions in Heilongjiang province. Poliovirus was identified from 72 samples, and the positivity rate was 51%.

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Mumps incidence in mainland China remains at a high level. Genotype F has been the predominant genotype of mumps virus (MuV) in the last 20 years in mainland China. To better understand the genetic characteristics of MuV in China, the sequences of the Small Hydrophobic (SH), Hemagglutinin-Neuraminidase (HN) and Fusion (F) genes of MuVs of genotype F collected during 2001-2015 were determined.

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With the implementation of mumps virus (MuV) vaccination in the expanded program on immunization (EPI) in mainland China since 2008, the incidence of mumps has decreased, and the natural epidemic pattern of mumps has slightly changed during 2013-2015. The two epidemic peaks (April-July and November-December) became less obvious than those observed from 2004 to 2012. Children and adolescents younger than 15, particularly in the five-to-nine-year-old age group, remain the target group and should be the focus of high-quality immunization activities in mainland China.

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The epidemiologic and genetic characteristics of mumps viruses detected in China from 1995 to 2010 were analyzed in this study. Mumps remains endemic in China with a high overall incidence rate. The incidence of mumps in Western China was higher than that in other regions of the country.

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Serological samples of healthy people were collected to obtain the levels of measles antibodies in different groups of people in Heilongjiang Province, China. Using quantitative enzyme-linked immunosorbent assays to measure the antibody levels, we found the lowest antibody positive rate and the lowest geometric mean concentration values in healthy people aged 15-39. This group is the population at high risk for adult measles in Heilongjiang Province, and is the focus of measles elimination work.

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