Risk factors for developing severe COVID-19 in China: an analysis of disease surveillance data.

Background: COVID-19 has posed an enormous threat to public health around the world. Some severe and critical cases have bad prognoses and high case fatality rates, unraveling risk factors for severe COVID-19 are of significance for predicting and preventing illness progression, and reducing case fatality rates. Our study focused on analyzing characteristics of COVID-19 cases and exploring risk factors for developing severe COVID-19.

Dynamics of Rodent and Rodent-borne Disease during Construction of the Three Gorges Reservoir from 1997 to 2012.

Objective: To investigate the impact of impoundment and active public health interventions on rodent populations and rodent-borne diseases in the Three Gorges reservoir region from 1997 to 2012.

Methods: Surveillance data from 1997 to 2012 were extracted from the Public Health Surveillance System of The Three Gorges established in 1997. Temporal changes in the incidences of hemorrhagic fever with renal syndrome (HFRS) and leptospirosis, rodent density, pathogen-carrying rates, and their correlations were analyzed.

[Epidemiological features of typhoid/paratyphoid fever in provinces with high incidence rate and in the whole country, in 2012].

Objective: Through analyzing the national statutory reporting data on typhoid, paratyphoid fever in 2012, we were trying to understand the whole picture of typhoid, paratyphoid fever at the national level as well as to understand the trends and characteristics of typhoid and paratyphoid fever in provinces with high incidence rate, so as to the development of prevention and control strategies of the diseases in those high-incidence rate provinces.

Methods: We descriptively analyzed the national typhoid and paratyphoid fever statutory reporting data which was reported through disease surveillance information reporting system in 2012.

Results: 11 998 cases with typhoid and paratyphoid fever were reported with 3 fatal ones, in 2012 in the whole country.

[Surveillance on the health status regarding vector-borne disease among people living in the Three Gorges Reservoir Area (1997 - 2009)].

Objective: To evaluate the impact on the health status of population in the area where the 'Three Gorges Reservoir Water Storage Project' had been operated and to provide references for the development of related disease control strategies.

Methods: In the Three Gorges Reservoir Area, 17 towns/streets in nine counties were chosen as surveillance points. Data on surveillance program would include infectious diseases, birth, death, biological agents etc.

[Epidemiological features of hand, foot and mouth disease in China, 2008 - 2009].

Objective: To clarify the seasonal and geographical difference and pathogen patterns so as to provide reference of prevention and control of the disease through analyzing the epidemic characteristics of reported hand-foot-mouth disease (HFMD) cases in China, 2008 - 2009.

Methods: We analysed the epidemiological data of HFMD from the Chinese national notifiable infectious diseases reporting system in 2008 and 2009.

Results: There were 488 955 and 1 155 525 reported HFMD cases in 2008 and 2009, in China, of which 1165 and 13 810 were severe and 126 and 353 were fatal, respectively.

[Outbreaks of noroviral gastroenteritis and their molecular characteristics in China, 2006 - 2007].

Objective: To acknowledge the epidemiology of gastroenteritis outbreaks caused by noroviruses and their genotypes.

Methods: Epidemiologic data and specimens were collected from 19 gastroenteritis outbreaks. 201 specimens were detected for norovirus, rotavirus, astrovirus, adenovirus and sapovirus by RT-PCR methods and PCR products were sequenced.

[Analysis on bacillary dysentery surveillance data collected from the National Surveillance System in 2007.].

Objective: To improve the national surveillance plan on bacillary dysentery and to increase the sensitivity of the surveillance system on the disease.

Methods: Data was collected through China Disease Reporting Information System (CDRIS) and National Sentinel Surveillance Sites on bacillary dysentery. Data from the CDRIS was compared with the data from the National Sentinel Surveillance to identify the exiting problems.

[Analysis of epidemiologic feature and genetic sequence of Sapovirus in China].

To investigate epidemiologic feature and genetic variance of Sapovirus among children in China, fecal specimens were collected from children under 5 years old with acute diarrhea from Feb 2006 to Jan 2007 in nine provinces including Anhui, Fujian et al. A total of 1,110 fecal samples were detected for Sapovirus by reverse transcriptase-PCR (RT-PCR). Ten samples (0.

[Identification and molecular study on vibrio cholerae in sea products].

Objective: To investigate the serologic type, phage-biotype and toxic factor of Vibrio cholerae isolated from different sea products, analyze the relation between the Vibrio cholerae in sea products and cholera epidemiology, and provide references for forecasting cholera epidemic situation and drawing out a preventing plan.

Method: The biotype of strains isolated was analyzed by using type and phage-biotype serological methods. The toxic gene was detected by PCR.

[Analysis on the status of Shigella spp antimicrobial resistance through data from the National Shigellosis Surveillance System in China, in 2005].

Objective: The Ministry of Public Health released the National Surveillance project on Shigellosis in August, 2005. This study was to reveal the antimicrobial resistance status of Shigella isolates through the National Shigellosis Surveillance System in 2005 in China, so as to provide evidence for the development of surveillance, prevention and cure of Shigellosis.

Methods: All the lab assistants received training from Chinese Center for Disease Control and Prevention.

[Investigation on status of pollution of vibrio cholera in seafood and aquatic products in 12 provinces of China in 2005].

Objective: To understand the pollution rates of vibrio cholera (V. cholera) in different seafood, aquatic products and their circulatory processes, so as to help making measures for cholera control and prevention.

Methods: Different seafood, aquatic products and breed water specimen collected from 12 provinces of China were tested from July to September in 2005.

[Preparation and characterization of monoclonal antibodies against SARS-associated coronavirus nucleocapsid protein].

Objective: To obtain monoclonal antibodies (McAbs) against severe acute respiratory syndrome (SARS) associated coronavirus (SARS-CoV) nucleocapsid (N) protein to develop diagnostic test for SARS and study the pathogenesis of the disease.

Methods: BALB/c mice were immunized with purified N protein of SARS-CoV. Hybridoma cell lines secreting monoclonal antibodies against SARS-associated coronavirus nucleocapsid were established after cell fusion with mouse splenic cells and SP2/0 cells.