Genetic characteristic of mumps virus from 2012 to 2016 and its serum antibody level among general healthy population during 2018-2020 in Jiangsu Province, China.

Mumps is a vaccine-preventable disease with high contagious capability. Its incidence declined rapidly since one dose of mumps vaccine was introduced into Expanded Program of Immunization (EPI) in 2008 in China. Nonetheless, the outbreaks of mumps remain frequent in China. Here we aim to assess herd immunity level followed by one-dose mumps ingredient vaccine and to elucidate the genetic characteristics of mumps viruses circulating in the post vaccine era in Jiangsu province of China. The complete sequences of mumps virus small hydrophobic(SH) gene were amplified and sequenced; coalescent-based Bayesian method was used to perform phylogenetic analysis with BEAST 1.84 software. Commercially available indirect enzyme-linked immune-sorbent IgG assay was used for the quantitative detection of IgG antibody against mumps virus. Our results show that genotype F was the predominant mumps viruses and belonged to indigenous spread, and most of Jiangsu sequences clustered together and formed a monophyly. The prevalence of mumps reached a peak in 2012 and subsequently declined, which presented an obvious different trajectory with virus circulating in other regions of China. The gene diversity of viruses circulating in Jiangsu province was far less than those in China. The antibody prevalence reached 70.42% in the general population during 2018 to 2020. The rising trend of antibody level was also observed. Although mumps antibody prevalence does not reach expected level, mumps virus faces higher pressure in Jiangsu province than the whole of China. To reduce further the prevalence of mumps viruses, two doses of mumps vaccine should be involved into EPI.

The genotype distribution and phylodynamic of measles viruses circulating in the east of China in postvaccine era, 2005-2017.

The increase of the evolutionary pressure will cause phylodynamics changes of viruses. In post-vaccine coverage era, measles viruses face more immune pressure than ever before. Vice versa, the phylodynamic changes may reflect herd immunity level provided by vaccination. In this study, we analyzed phylodynamic characteristics of measles viruses isolated from 2005 to 2017 in Jiangsu province of China using nucleoprotein gene sequences of measles viruses. The phylogenetic tree was constructed with Markov chain Monte Carlo algorithm. The mean gene distance within each group was computed with MEGA7.0 software. Our results showed that a decline trend is observed in the gene distance of nucleoprotein gene with time as well as incidence of measles from epidemic surveillance system. Two clusters of H1a genotype show cocirculation of multiple variants in early years and the disappearance of most variants with time. We explore the phylodynamic of measles virus under high immune pressure. Our findings highlight that phylodynamic of measles viruses is a helpful tool to assess the effectiveness of epidemic control.

First Detection of a Cluster Novel HIV-1 Second-Generation Recombinant (CRF01_AE/CRF07_BC) among Men Who Have Sex with Men in Nanjing, Eastern China.

INTRODUCTION: A large number of unique recombinant forms have been found in China in recent years. This study aimed to report on a cluster of novel HIV-1 recombinants. METHODS: We constructed phylogenetic trees using the maximum likelihood (ML) method with 1,000 bootstrap replicates in IQ-TREE 1.6.8 software and determined recombination break points using SimPlot 3.5.1. RESULTS: Overall, 9 near-full-length genome (NFLG) sequences were reported in this study, including 1 circulation recombinant form (CRF)01_AE NFLG sequence and 8 highly similar novel HIV-1 second-generation recombinants composed of CRF01_AE and CRF07_BC (CRF105_0107) isolated from a cluster HIV-positive male subjects infected among men who have sex with men (MSM) in Nanjing, eastern China. The phylogenetic analysis of NFLG showed 1 sequence named "nj16" to have at least 11 breakpoints inner virus and 7 other sequences to have at least 10 breakpoints inner virus. Our findings further showed as follows: first, this is the first time that a cluster of novel CRF105_0107 HIV-1 strains were identified among MSM in Nanjing, Jiangsu. Second, the Chinese "4a" cluster of CRF01_AE which mainly circulating in northern China has spread in Jiangsu for more than 15 years. Third, HIV-1 recombination events were active in Nanjing city, and novel recombinants could spread rapidly through some small-scale transmission networks. CONCLUSION: The continued emergence of novel recombinant HIV-1 strains in Nanjing suggests dynamics and complexity in the HIV epidemic among MSM in Jiangsu province. Further investigations and molecular epidemiological research should be taken to monitor and understand transmission networks among MSM.

An acute gastroenteritis outbreak associated with breakfast contaminated with norovirus by asymptotic food handler at a kindergarten in Shenzhen, China.

BACKGROUND: An outbreak of acute gastroenteritis occurred in a kindergarten located Shenzhen City on March 4, 2018. We were invited to investigate to the risk factors associated with this outbreak. METHODS: We conducted retrospective cohort-studies on three different groups of subjects in order to figure out the difference of incidence of acute gastroenteritis among subjects of different activities on March 2: group one consisted of people who attended the Lantern festival activities; group two consisted of children and employees who ate breakfast and bread provided by the kindergarten; and groups three consisted of children and employees who did not eat breakfast or bread provided by the kindergarten. Fecal, anal swabs, dishware swabs and hand swabs specimens were collected in the study. Bacteria known to cause acute gastroenteritis were cultured. Viruses associated with acute gastroenteritis were tested using real-time PCR. Capsid gene fragment of 557 bp of norovirus was amplified and sequenced. The phylogenetic tree was constructed with MEGA 7.0 using neighbor-joining method based on capsid gene fragment of norovirus. RESULTS: A total of 143 suspected cases were identified in this outbreak. Diarrhea happened more often in adults than in children while emesis and bellyache were more frequently found in children than in adults. Higher AGE incidence was observed in group 2, children and employees who had breakfast in the kindergarten on March 2, as well as in group 3, and among employees who eating bread involved in breakfast provided on March 2. Five anal swab specimens were positive for norovirus. All noroviruses belongs to group II.3 and have an identity more than 99%. CONCLUSION: A chef, as an asymptomatic carrier with norovirus, was the infectious resource in this outbreak. He contaminated breakfast food provided on March 2. Although morning check is implemented in kindergartens of China, employees are often excluded in morning check. Our finding highlights the importance of morning check covering employees and periodical training for cooks.

The characteristics and trend of adverse events following immunization reported by information system in Jiangsu province, China, 2015-2018.

OBJECTIVE: Adverse events following immunization is an important factor influencing public trust in vaccination. Publicizing its incidence timely can increase public trust. The aim of this study is to describe the incidence and characteristics of adverse events following immunization in Jiangsu province of China from 2015 to 2018. METHODS: All information of adverse events following immunization (AEFIs) was gained from Jiangsu Province Vaccination Integrated Service Management Information System. The reported AEFI trend was analyzed using Chi-square test. RESULTS: A total of 77,980 AEFI cases were reported through the AEFI system; Among which, 77,731 were classified as non-serious AEFI cases and 249 were serious AEFI cases. The male to female ratio was 1.31:1, cases less than 7 years old accounted for 97.7%. The total estimated AEFI rate was 62.70/100,000 doses. By severity, 60.75/100,000, 4.46/100,000 and 0.11/100,000 AEFI cases were common vaccine reaction, rare vaccine reaction, and serious rare vaccine reaction, respectively. The top two serious AEFI were thrombocytopenic purpura and febrile. The incidence rates showed the increasing trend and the linear trend of the increasing incidence rates passed the significant test at 0.05 levels. CONCLUSION: The sensitivity of AEFI monitoring in Jiangsu Province is increasing and higher than the national average and most countries. The majority of AEFI cases were common adverse reactions, while the serious vaccine reactions caused by vaccines were extremely low. To elevate the sensitivity of AEFI surveillance may reduce the incidence of developing serious AEFI cases.

Measles Virus Imported by International Traveler in Jiangsu Province of China, in 2018 and 2019.

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.

The inference of HIV-1 transmission direction between HIV-1 positive couples based on the sequences of HIV-1 quasi-species.

BACKGROUND: To infer transmission direction of a HIV transmission chain is helpful not only in legal jurisdiction but also in precise intervention to prevent HIV spread. Recently, the direction of transmission is inferred by whether paraphyletic-monophyletic (PM) or a combination of paraphyletic and polyphyletic (PP) topologies is observed or not between the sequences of source and recipient in the phylogenetic tree. However, paraphyly between them often declines over time and may disappear between spouses due to bidirectional transmission after primary infection. In this study, our aim is to test the reliability of inferring HIV transmission direction between epidemiologically linked HIV-1 positive couples using whether or not paraphyly is observed in phylogenetic tree. METHODS: HIV quasi-species were sequenced using PCR product clones, and then Bayesian analysis of molecular sequences with MCMC was employed to construct phylogenetic relationship of env, gag, pol gene fragments of HIV-1 positive couples using BEAST software. RESULTS: Our results showed that all sequences of seven couples except pol sequences of couple 12 and 13 form their own monophyletic cluster in phylogenetic tree including the closest control sequences from GenBank or other studies on local samples, which are supported by significant Bayesian posterior probabilities more than 0.9932. Of seven couples, paraphyly is only observed in phylogenetic tree constructed with env and pol gene sequences of three couples and gag gene sequences of four couples. Paraphyly is not observed in half of HIV positive couples. Pol sequences of couple 13 is separated by Blast selected controls; pol sequences of couple 12 in phylogenetic tree is supported by a lower Bayesian posterior value. CONCLUSION: Paraphyly relationship between sequences of donator and recipient is only observed among partial HIV-1 positive couples with epidemiological link. Phylogenetic relationship is not always the same when various gene regions of HIV are used to conduct phylogenetic analysis. The combination of phylogenetic analysis based on various gene regions of HIV and enough epidemiology investigation is essential when inferring transmission direction of HIV in a transmission chain or in one couple. However, while observed paraphyly can be used to infer transmission direction in HIV-1 positive couple, no observed paraphyly cannot deny it.

The declining antibody level of measles virus in China population, 2009-2015.

BACKGROUND: To eliminate measles, the coverage of more than 90% vaccine is required in China. Nonetheless, the measles incidence still reached to 3.88 per 100,000 in 2014, which is far more than the target of 1 per 1,000,000. Moreover, there is little national surveillance to measles antibody level indicating herd immunity status in China. METHODS: We detected the level of antibody to measles using commercially available indirect enzyme-linked immunosorbent IgG assays, and calculated the protection rate of population (PRP) to measles virus infection among health peoples in China. RESULTS: During the years 2009-2015, among the Chinese population aged 0-56, PRP was 94.7, 91.6, 91.6, 84.2, 82.1, 81.0, 75.4%, respectively. Among all age bands, the PRP is lowest among children less than 12-month-age, followed by people over 15 years old. CONCLUSION: Measles antibody level among healthy population has been declined since 2012, supplemented measles vaccination activity may be necessary to eliminate measles in China.

Subtype distribution of hepatitis C virus in Jiangsu, China.

Hepatitis C virus (HCV) genotype distribution varied by regions and transmission modes. In this study, we investigated HCV genotype distribution in five cities of Jiangsu, China, all of which are located in the Yangtze River Delta Region. A total of 363 samples were collected during 2011-2012. C/E2 and NS5B fragments of HCV were amplified using a multiple RT-nested PCR strategy and subjected to sequencing. Phylogenetic analysis was performed for HCV genotyping. Among 106 PCR positive cases, HCV subtypes 1a (0.9%), 1b (61.3%), 2a (15.1%), 3a (4.7%), 3b (9.4%), 6a (6.6%), and 6n (1.9%) were detected. Together with our previous data, we found that HCV subtypes were more among injection drug users (IDUs) (nine) than among general population (GP) (six), and the most common subtype among GP was 1b (73.9%), followed by 2a (14.5%), while the top four common subtypes among IDUs were 3a, 1b, 3b, and 6a, with similar prevalence rates (24.4%, 22.7%, 20.9%, and 17.4%, respectively). There were nine HCV subtypes prevalent among IDUs in Jiangsu, more than those in Xinjiang, Hubei, Yunnan, Guangxi, Guangdong, and Hong Kong. The top four common subtypes among IDUs in Jiangsu covered all the two most common HCV subtypes (except 6n subtype) observed in six targeted provinces/region. These results suggested that Jiangsu may be an important gathering place for various HCV subtypes and the gathering may be involved in the large scale of population migration from other regions of China to Eastern China.

Low prevalence of the transmitted HIV-1 drug resistance among newly diagnosed HIV-1 individuals in Jiangsu Province, China during 2009-2011.

BACKGROUND: Prevalence of The transmitted HIV drug resistance (THDR) has been reported in many countries. In China, the low level THDR was found in only a few provinces. To know the transmitted HIV drug resistance in east of China, we investigated THDR during 2009-2011 in Jiangsu province of China. METHODS: Between January and August of 2009, 2010, and 2011, we consecutively collected 50, 54, 53 blood specimens respectively from qualified individuals at surveillance sentinel sites in Jiangsu province according to protocol of HIV Drug Resistance Threshold Survey (HIVDR-TS) recommended by WHO. The region of pol gene including protease and partial retro-transcriptase was amplified, sequenced and edited. Then the sequences were submitted to HIV drug resistance database to analysis transmitted HIV drug resistance mutations using Calibrated Population Resistance tool. The reference sequences of different HIV-1 subtypes were downloaded from HIV database and Genebank. The phylogenetic trees were inferred using the neighbor-joining method. RESULTS: Our results show that THDR has been at low level from 2009 to 2011, only K101E and V179D mutation was detected which did not belong to the major HIV-1 drug resistance mutations. Phylogenetic analysis showed that CRF01_AE is the predominant subtype, and followed by CRF07_BC and B subtype. Subtype B consists of the two distinct clusters. CONCLUSIONS: The low level of THDR suggests that anti-retroviral treatment was implemented more effectively and THDR surveillance should be conducted two years later in Jiangsu province of China. CRF01_AE has become the predominant subtype and dual infection of HIV may be common in Jiangsu province.

Advanced schistosomiasis reappeared after curing seemingly being cured for over 20 years and without known history of reexposure to Schistosoma japonicum.

Schistosomiasis is an intravascular disease caused by parasitic trematode worms of the genus Schistosoma. It is estimated that more than 200 million people are infected in the world, and 800 million are at risk of infection. The main lesions are due to eggs trapping in tissue which can lead a series of pathogenic effect relative to immune response. Therefore, killing and eradicating eggs in tissue is often the target to treat schistosomiasis. Here, we report 75 patients who being cured for over 20 years developed into advanced schistosomiasis. A total of 90 patients with a diagnosis of schistosomiasis in various periods were enrolled. Of them, all patients have liver fibrosis, splenectomy was performed in 48.0 %, 42.7 % have splenomegaly, and 30.0 % have portal hypertension. No patients were infected with HBV. Moreover, all patients have not been to Schistosoma-endemic regions. Our results showed that there are other factors leading to schistosomiasis progress besides eggs as well as Schistosoma mansoni.

[Analysis of the five-year effectiveness of highly active antiretroviral therapy among 200 HIV/AIDS patients in Jiangsu province].

OBJECTIVE: To analyze the five-year effectiveness of the people living with HIV/AIDS who initially received highly active antiretroviral therapy (HAART) in Jiangsu province. METHODS: HIV/AIDS initially received HAART from 1 Jan 2005 to 31 May 2014 in Jiangsu province with the CD4(+)T cell count tested in baseline, 6 months, 1 year, 2 years, 3 years, 4 years and 5 years after treatment initiation were selected. According to their retrospectively collected baseline and follow-up data, statistical analysis was performed using SPSS 16.0 software to analyze the variation of CD4(+)T counts and its impact factors in different times after treatment initiation. RESULTS: A total of 200 patients were included. A total of 134 patients were men, and 66 were women, the ratio of male to female was 2.03: 1; mean age was (39.7 ± 10.3) years old; 69.0% (138/200) of the patients married; 53.0% (106/200) as the most were infected with HIV through heterosexual transmission, and followed by men who have sex with men (MSM) (25.5%, 51/200); taken together as 78.5% (157/200).58.5% (117/200) were treated in the CDC. The mean (95%CI) baseline CD4(+)T cell count of cases was 106.9 (93.3-120.5) cells/µl; the CD4(+)T count tested in 6 months, 1 year, 2 years, 3 years, 4 years and 5 years after treatment initiation were 107.3, 152.9, 221.6, 260.0, 281.3 and 316.4 cells/µl more than baseline respectively; the CD4(+)T count after treatment initiation has increased over time (F = 201.06, P < 0.01) . The mean(95%CI) CD4(+)T count tested in 5 years after treatment initiation can increase to 540.7(445.4-635.9) cells/µl with a baseline CD4(+)T count more than 200 cells/µl, but in the subgroups with a baseline CD4(+)T count less than or equal to 50 cells/µl, 51-100 cells/µl, 101-150 cells/µl and 151-200 cells/µl, it only can reach to 431.4 (375.9-487.0), 400.0 (339.9-460.2), 380.3 (330.6-430.0) and 412.1 (369.3-454.8) cells/µl respectively. The mean (95%CI) CD4(+)T count tested in 5 years after treatment initiation with 1 baseline symptom categories can increase to 449.2 (392.2-506.2) cells/µl, while 409.1(317.8-500.5)cells/µl in the subgroup with baseline symptom categories more than or equal to 2. The CD4(+)T after treatment increased slowly associated with a lower baseline CD4(+)T count level and more baseline symptom categories (F values were 3.96 and 2.35, P < 0.01). CONCLUSION: It has a remarkable effectiveness for HIV/AIDS treatment in Jiangsu province. The patients with a baseline CD4(+)T count more than 200 counts/µl have a better immune function recovery.

High prevalence of antibiotic resistance and molecular characterization of integrons among Shigella isolates in Eastern China.

A total of 747 Shigella isolates were collected from hospitals in Jiangsu Province of China. Susceptibilities to antimicrobials and integrons were tested. A total of 78.3% of S. flexneri isolates and a total of 74.3% S. sonei isolates were resistant to at least three antibiotics. Of the Shigella isolates, 74.7% had integron I and 82.6% had integron II. The conjunction of the high prevalence of integrons in Shigella and high resistance to antimicrobials will lead to rapid dissemination of resistant genes in this region.

Mycoplasmas infection in male HIV/AIDS patients in Jiangsu, China.

Mycoplasmas are widely distributed among animals, plants, and human. The four species namely, Mycoplasmas genitalium(Mg), Mycoplasmas fermentans(Mf), Mycoplasmas pentrans(Mpe), Mycoplasmas pirum(Mpi) are also called AIDS-associated mycoplasmas due to their involvement in the development and outcome of AIDS. To investigate the infection prevalence of Mg, Mf, Mpe and Mpi among male HIV/AIDS patients in Jiangsu Province and to analyze the relationship between pathogenic mycoplasmas and cellular immune function of them. First void urine and venous blood samples were collected and epidemiology questionnaires were administered after informed consent. Nested PCR was performed to determine the infection of Mg, Mf, Mpe and Mpi while ELISA assay was applied to detect interleukin-2(IL-2), interferon-γ(IFN-γ) and tumor necrosis factor-α(TNF-α). SAS 9.0 software was applied to analyze the data. A total of 713 HIV/AIDS patients were recruited in this study. The overall infection rates of Mg, Mf, Mpe and Mpi are 27.9%, 9.7%, 1.0% and 18.4% respectively. Generally, the infection rates of Mg(χ(2) = 10.311, P = 0.006) and Mpi were declined as the CD4+ cell counts increased, while Mf infection was higher in CD4+ T cell>350/µl group. The levels of cytokines are different with the variance of mycoplasmas infection. Mycoplasma infection among male HIV/AIDS patients is associated with changes in cellular immune response (cytokines). However, the affect of mycoplasmas on the immune function is complex, further studies are still required to elucidate whether mycoplasmas interact with HIV by interfering host immune system.

An outbreak of norovirus gastroenteritis associated with a secondary water supply system in a factory in south China.

BACKGROUND: Between September 17 and October 3, 2009, hundreds of workers employed in a manufacturing factory in Shenzhen, a city in south China developed a sudden onset of acute gastroenteritis. A retrospective cohort study is designed to identify the risk factors and control this outbreak. METHODS: Information on demographic characteristics, working place, the history of contact with a person having diarrhea and/or vomiting, drink water preference and frequency, eating in the company cafeteria or outside the company, hand-washing habits and eating habits is included. Furthermore, in order to find the contamination source, we investigated the environment around the underground reservoir and collected water samples from the junction between municipal supply water system and underground reservoir to test potential bacteria and virus, examine the seepage tracks on the wall of the underground reservoir from the side of septic tank, and check the integrity and attitude of this lid. Relative risk was presented and Chi-square test was performed. All the analyses were performed with OpenEpi software version 2.3.1 online. RESULTS: The cohort study demonstrated that the workers who had direct drink water were 3.0 fold more likely to suffer from acute gastroenteritis than those who consumed commercial bottled water. The direct drinking water, water of the tank of buildings, and the underground reservoir were positive only for norovirus. Norovirus was also detected from stool and rectal swab samples from patients with acute gastroenteritis. The underground reservoir was found to be the primary contamination source. Further environmental investigation showed that the norovirus contaminated substance entered into the underground reservoir via access holes in lid covering this underground reservoir. CONCLUSION: This acute gastroenteritis outbreak was caused by the secondary supply system contaminated by norovirus in this factory. The outbreak of gastroenteritis cases caused by norovirus frequently occurred in China due to a lack of surveillance and supervision, and due to faults in the construction of such water systems. Therefore, more attentions should pay to the secondary supply water system in China.

Post-marketing safety surveillance for both CRM197 and TT carrier proteins PCV13 in Jiangsu, China.

Background: This study is to evaluate the safety of two kinds of PCV13 carriers by monitoring the occurrence of adverse event following immunization (AEFI) after the launch of two kinds of PCV13 carriers in Jiangsu Province, China. Methods: The AEFI Information System (CNAEFIS) of mainland China was used to monitor the incidence and classification of adverse reactions of the CRM197-carrier protein PCV13 and TT-carrier protein PCV13 vaccines. Results: There was no statistical difference between the cumulative reported incidence of AEFI between the two vaccines from 2020 to 2022 (χ2 = 1.991, p < 0.158). 96.62% of the AEFIs were classified as common reactions; rare reactions and coincidental events only accounted for 2.99 and 0.39% of all the AEFI cases, respectively. Redness (2.6 cm-5 cm) is the commonest symptom at the injection site for both vaccines. More than 97% of AEFIs occurred between 30 min and 3 days after administration for both types of PCV13. Conclusion: Both vaccines perform well in terms of safety. We did not identify any new/unexpected safety concern from the NAEFISS during a 4 years timespan.

The characteristics of HIV-1 subtype B on phylogenetic dynamic and molecular transmission network in Fuyang City, China, 2011 to 2019.

Introduction: HIV-1 subtype B, as once one of the earliest strains introduced into mainland China rapidly spread in commercial plasma donors and heterosexuals in 1990s. Here, we aim to investigate the origin and evolutionary history of HIV-1 subtype B in Fuyang city, China. Methods: We collected sequences tested from Fuyang in the east of China where higher prevalence of HIV-1 among commercial plasma donors and heterosexuals to construct a phylogenetic tree using the Markov chain Monte Carlo (MCMC) algorithm, infer molecular transmission network using TN93 model and visualize it with Cytoscape software. Results and discussion: Our results showed that >99% of subtype B sequences belonged to Thai B. The sequences from Fuyang often cluster closer to those from other its adjacent cities, which clustered together and formed a monophyletic cluster. HIV-1 B circulating in Fuyang dates back to approximately 1990. Among the 1,437 sequences, 166 clustered at a genetic distance of ≤1.2%, resulting in 73 clusters. The degree of clustering with at least one other person was 11.55%. Among the transmission clusters, 50 (80.65%) comprised two individuals. Most clusters consisted of both heterosexual transmission routes and men who have sex with men. Phylogenetic and molecular network analyses revealed a common origin with neighboring regions in mainland China, local onwards transmission after its introduction, and a limited clustering degree. However, at least two co-existing transmission routes in most transmission clusters imply a greater challenge in controlling the spread of HIV-1. Our findings highlight the value on tailoring prevention interventions by combination of molecular surveillance and epidemiology.

Low awareness of HPV infection and willingness of HPV vaccination among Chinese male college students in the east of China.

Introduction: Human Papillomavirus (HPV) vaccine has proven to play a major role in preventing sexually transmitted diseases and related cancers among both men and women. However, the coverage of the HPV vaccination is still limited. Objective: The study aims to evaluate the awareness of HPV and HPV vaccine, as well as the willingness to take HPV vaccine, especially factors influencing vaccination willingness among male college students. Methods: We conducted a cross-sectional investigation among male college students from six colleges in Jiangsu, China. A structured questionnaire was used to investigate the subjects' basic information, behavior habits, cognition of the HPV vaccine, and intention for HPV vaccination. Multivariate analysis modes were used to analyze the influencing factors of vaccine awareness and willingness. Results: We found that among 912 participants, only 24.34% of the participants had a "good knowledge" of HPV and HPV vaccine, and 34.54% showed a "positive attitude" toward the HPV vaccine after obtaining knowledge of HPV and its vaccine. Factors such as immune persistence, side effects, pricing strategy, and participants' self-assessment of HPV infection were the main factors influencing the HPV vaccination. Conclusion: Strengthening health education on the HPV vaccination and finding appropriate ways to solve the problem of "vaccine hesitancy" will be effective in improving the coverage of the HPV vaccine and preventing related diseases. In addition, the lifting of restrictions on HPV vaccination for men in China may also prove useful.

Isolation and characterization of a Sabin 3/Sabin 1 recombinant vaccine-derived poliovirus from a child with severe combined immunodeficiency.

An 8-month-old child diagnosed with severe combined immunodeficiency (SCID) was found to be excreting vaccine-derived poliovirus (VDPVs). Five stool samples from the child and stool samples from 24 contacts were collected during the following 7 months. Complete genome sequence by next generation sequencing (NGS) identified 0.7 to 1.4% nucleotide substitutions in the capsid P1 region of the first and the last isolates compared with Sabin 3 strain. Simplot analysis revealed that all isolates were Sabin 3/Sabin 1 recombinants, sharing a single recombination breakpoint in the 2C region. Multiple nucleotide variants were identified in the 5'UTR (T472→C and G395→A); amino acid mutations were identified in residues at VP1-6 (Thr to Ile), VP1-105 (Met to Thr), VP1-286 (Arg to Lys), VP2-155 (Lys to Glu), VP3-59 (Ser to Asn) and VP3-91 (Phe to Ser). These variants were commonly observed in other PV strains, which may contribute to attenuation and temperature sensitivity. None of the 24 tested contacts of the patient and related transmits was found to be infected with poliovirus. Our study provides a rapid and reliable method for the characterization of VDPV research in Poliovirus infection. In post-OPV era, immunodeficient people with persistent and chronic infection remain a major challenge for polio eradication in China.

Waning immunity and potential asymptomatic infection in 3-7 years old children who received one dose of measles-mumps-rubella vaccine: A 4-year prospective study.

BACKGROUND: Mumps outbreaks in adolescents who received two doses of measles-mumps-rubella vaccine (MMR) during childhood have been reported worldwide. In China, one dose of MMR administered in children aged among 18-24 months has a limited effect on the mumps epidemic. There are limited prospective studies evaluating the mumps immunity profile of children aged 3-7 years who received one dose of MMR. This study aimed to describe mumps immunity profile over a span of 4-years in kindergarten and primary school children. METHODS: An observational, prospective study on one-dose MMR in children aged 3-7 years who underwent blood sample collection in 2015, 2016, and 2018 was conducted from 2015 to 2018. The seropositivity and geometric mean concentration of mumps IgG antibodies over time were analyzed. RESULTS: A total of 3346 eligible children aged 3-7 years who underwent three rounds of blood sample collection were included. The overall seropositivity (79.6%) in 2015 was significantly higher than those recorded in 2016 (73.1%) and 2018 (71.4%). Approximately 11.6-15.9% of the participants were seropositive for mumps in 2015, and converted to negative in 2016. Meanwhile, 11.1-14.6% of the participants were seropositive for mumps in 2016, and the results converted to negative in 2018. Over 6.1-7.4% of the participants had asymptomatic infection from 2015 to 2016, while 9.0-9.9% of the participants were infected without clinical symptoms from 2016 to 2018. CONCLUSIONS: Kindergarten and primary school children who only received one dose of MMR were at higher risk of developing mumps. Waning immunity, seronegative conversion, and asymptomatic infection coexist in children who received one dose MMR. Determining the optimal age for administering the second dose of MMR in children should be prioritized to improve the control and prevention of mumps in China.