Epidemiological features and viral shedding in children with SARS-CoV-2 infection.

A pandemic of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection broke out all over the world; however, epidemiological data and viral shedding in pediatric patients are limited. We conducted a retrospective, multicenter study, and followed-up with all children from the families with SARS-CoV-2 infected members in Zhejiang Province, China. All infections were confirmed by testing the SARS-CoV-2 RNA with real-time reverse transcription PCR method, and epidemiological data between children and adults in the same families were compared.

Risk factors for avian influenza virus in backyard poultry flocks and environments in Zhejiang Province, China: a cross-sectional study.

Background: Human infection of avian influenza virus (AIV) remains a great concern. Although live poultry markets are believed to be associated with human infections, ever more infections have been reported in rural areas with backyard poultry, especially in the fifth epidemic of H7N9. However, limited information is available on backyard poultry infection and surrounding environmental contamination.

Nosocomial transmission of avian influenza A (H7N9) virus in China: epidemiological investigation.

Study Question: Can avian influenza A (H7N9) virus be transmitted between unrelated individuals in a hospital setting?

Methods: An epidemiological investigation looked at two patients who shared a hospital ward in February 2015, in Quzhou, Zhejiang Province, China. Samples from the patients, close contacts, and local environments were examined by real time reverse transcriptase (rRT) polymerase chain reaction (PCR) and viral culture. Haemagglutination inhibition and microneutralisation assays were used to detect specific antibodies to the viruses.

Human infection and environmental contamination with Avian Influenza A (H7N9) Virus in Zhejiang Province, China: risk trend across the three waves of infection.

Background: The third wave of H7N9 cases in China emerged in the second half of 2014. This study was conducted to identify the risk trends of H7N9 virus in human infections and environment contamination.

Methods: A surveillance program for H7N9 virus has been conducted in all 90 counties in Zhejiang since March 2013.

Evidence for H5 avian influenza infection in Zhejiang province, China, 2010-2012: a cross-sectional study.

Background: The first outbreak of H5N1 highly-pathogenic avian influenza (HPAI) virus associated with several human deaths occurred in 1997 in Hong-Kong, China. While H5N1 virus infection in poultry workers has been studied in some detail, little is known about the environmental risk factors of the H5 avian influenza virus infection in China.

Methods: A cross-sectional study was performed to evaluate the environmental load of H5 viruses in poultry-contaminated environments and to explore potential risk factors associated with infection in poultry workers between October 2010 and March 2012.

[Analysis on coverage rate of primary immunization of measles vaccine among migrant children in Yiwu, Zhejiang province from 2007 to 2010].

Objective: To investigate the coverage rate of primary immunization of measles containing vaccine (MCV1) among migrant children in Yiwu,Zhejiang province.

Methods: Household cluster sampling survey and probability proportion to size sampling method were adopted. A total of 967 migrant children born from 1st July 2007 to 1st July 2010 and their caregivers were selected as target population.

[Clinical and epidemiological characteristics of the 6 confirmed human cases with novel influenza A (H7N9) virus infection in Zhejiang].

Objective: To explore the clinical spectrum, geographic location of human H7N9 avian influenza as well as the characteristics of population at high risk of infection, in order to develop strategies for the prevention and control of the infection. Clinical and epidemiological characteristics on the 6 confirmed human cases in Zhejiang were also analyzed.

Methods: Real-time fluorescent quantitative PCR was used to test the nucleic acid of human H7N9 avian influenza infection, from pharyngeal swabs of the patients and their close contacts.

Waning immunity to measles in young adults and booster effects of revaccination in secondary school students.

The increasing proportions of adult cases were observed in the recent measles outbreaks in Zhejiang Province, China. In order to identify the high-risk age groups of measles for targeted intervention, a seroprevalence survey of measles antibody was conducted among 1961 participants aged 0-60 years randomly selected by age-stratified purpose sampling, and the effect of revaccination program in secondary school was evaluated in Zhejiang Province. The adjusted overall seropositivity rate of measles was 88% (95% confidence interval [CI]: 86-89%) with geometric mean titers (GMT), 976±86 mIU/ml.

[Epidemiological effects of the A (H1N1) influenza vaccine immunization program on students].

Objective: To evaluate the epidemiological effects of vaccine immunization program related to A (H1N1) influenza in the middle school students.

Methods: Non-randomized clinical trial was designed to assess the A (H1N1) influenza vaccine on its efficacy. 14 883 students from 8 middle schools in Zhejiang province were recruited and classified into vaccinated or control groups, based on the status of immunization with A (H1N1) influenza vaccine.

[An outbreak of measles among unvaccinated migrant population in Zhejiang province, from June to August, 2010].

Objective: On July 6, 2010, the parents of a patient with confirmed measles reported several suspected measles patients with fever and rash in their village. An investigation was carried out to verify and understand the cause of the outbreak.

Methods: Several suspected cases had an onset of fever and rash in this and other neighboring villages during June 1 to August 3, 2010.

[Case-control study on epidemiology factors of measles in Zhejiang Province in 2008].

Objective: In order to analysis the main factors of measles prevalence in 2008, and to provide evidence for establishing scientific strategies on measles elimination.

Methods: 1:1 matched case-control study was conducted in 3 cities, and the conditional logistic regression was used to analyse the risk factor of measles.

Results: 358 matched pairs (716 objects) were investigated.

[Safety and immunogenicity of lyophilized live attenuated domestic varicella vaccine].

Objective: To evaluate the safety and immunogenicity of the lyophilized live attenuated domestic varicella vaccine of Oka strain in Zhejiang province.

Methods: 785 susceptible children aged 1-13 years, who had no history of VZV infection and had not been immunized, were observed. RESULTS The results showed that 2.

[A safety assessment on adverse reaction of recombinant B-subunit/inactivated whole cell oral cholera vaccine among non-infected population].

Objective: To observe the safety of recombinant B-subunit/inactivated whole cell (rBS/WC) oral cholera vaccine among non-infected population.

Method: A method of double-blind and case control was conducted randomly. 3041 non-infected persons who aged from 5- to 60-years-old were divided randomly into 3 groups, including 2 vaccine groups and 1 placebo group.

[Study on relationship between hepatitis B virus DNA load and genotype with large envelope protein].

Objective: To explore the relation between hepatitis B virus DNA load and genotype with the level of large envelope protein.

Methods: Serum HBV DNA was quantitively detected by using real time polymerase chain reaction (RT-PCR). The LHBs were detected by using enzyme linked immuno sorbent assay (ELISA) and HBV markers were detected by time differentiate immunofluorescence assay in 140 serum samples collected from chronic hepatitis B patients.

[The emergence of candidate pathogenicity island 89K DNA sequence of Streptococcus suis isolated from sporadic patients in Zhejiang province].

Objective: To identify the presence of candidate pathogenicity island 89K DNA sequence of Streptococcus suis serotype 2 (SS2) strains isolated from patient in Zhejiang province.

Methods: Genes and DNA fragments were amplified by PCR, using specific primers, and three amplified fragments of the 89K sequence were directly sequenced. The results were analyzed using software related to bioinformatics and epidemiology.

[Study on a 10-year protective effects of vaccination against hemorrhagic fever with renal syndrome].

Objective: To evaluate the epidemiological and serological efficacy after 10 years of vaccination against hemorrhagic fever with renal syndrome (HFRS) vaccines in Zhejiang province.

Methods: One county was randomly chosen as the research unit with all the healthy people between 16 and 60 years old were equally divided into study and control groups. The study group was vaccinated.

[Serological surveillance on vaccine against hemorrhagic fever with renal syndrome].

Objective: To observe the serological and epidemiological efficacy of hemorrhagic fever renal syndrome (HFRS) vaccine in Zhejiang province.

Methods: Immunofluorescent antibody assay and Mcro-CPE method were used to test specific IgG antibody and the titer of neutralizing antibody.

Results: Two weeks after the injection of the third dose, the sero-conversion rates by both immunofluorescent antibody test (IgG) and neutralization test were 100.