Epidemiological characteristics of norovirus acute gastroenteritis outbreaks and influencing factors in China, 2007-2021 / 中华流行病学杂志

Objective: To analyze the epidemiological characteristics of norovirus-caused acute gastroenteritis outbreaks in China, identify the factors influencing the scale of outbreaks, and provide scientific evidences for early control of norovirus infection outbreaks. Methods: The descriptive epidemiological analysis approach was applied to analyze the incidence of national norovirus infection outbreaks by using the data from the Public Health Emergency Event Surveillance System in China from January 1, 2007 to December 31, 2021. The unconditional logistic regression model was applied to analyze the risk factors that affected the outbreaks' scale. Results: A total of 1 725 norovirus infection outbreaks were recorded in China from 2007 to 2021, with an upward trend in the number of the reported outbreaks. The southern provinces had their annual outbreak peaks from October to March; the northern provinces had two outbreak peaks from October to December and from March to June annually. The outbreaks occurred mainly in southeastern coastal provinces with a trend of gradual spread to central, northeastern and western provinces. The outbreaks mainly occurred in schools and childcare setting (1 539 cases, 89.22%), followed by enterprises and institutions (67 cases, 3.88%) and community households (55 cases, 3.19%). Human to human transmission was the main infection route (73.16%), and norovirus GⅡ genotype was the predominate pathogen causing the outbreaks (899 cases, 81.58%). The time interval between the onset of the primary case and the outbreak reporting M (Q1, Q3) was 3 (2, 6) days and the case number of the outbreak M (Q1, Q3) was 38 (28, 62). The timeliness of outbreak reporting was improved in recent years and the scale of the outbreaks showed a decreasing trend over the years, the differences in reporting timeliness and outbreak scale among different settings were significant (P<0.001). The factors that affected outbreaks' scale included the outbreak setting, transmission route, outbreak reporting timeliness and type of living areas (P<0.05). Conclusions: From 2007 to 2021, the number of the norovirus-caused acute gastroenteritis outbreaks increased in China and the more areas were affected. However, the outbreak scale showed a decreasing trend and the outbreak reporting timeliness was improved. It is important to further improve the surveillance sensitivity and reporting timeliness for the effective control of the outbreak scale.

Epidemiological characteristics of typhoid fever and paratyphoid fever in China, 2004-2020 / 中华流行病学杂志

Objective: To analyze the incidence trend and epidemiological characteristics of typhoid fever and paratyphoid fever in China from 2004 to 2020, understand the high-incidence population and hotspot areas, and provide evidences to develop more targeted prevention and control measures. Methods: The descriptive epidemiological method and spatial analysis method were applied to analyze the epidemiological characteristics of typhoid fever and paratyphoid fever in China during this period by using the surveillance data collected from the National Notifiable Infectious Disease Reporting System of Chinese Center for Disease Control and Prevention. Results: A total of 202 991 cases of typhoid fever were reported in China from 2004 to 2020. More cases occurred in men than in women (sex ratio: 1.18∶1). Most cases were reported in adults aged 20-59 years (53.60%). The incidence rate of typhoid fever decreased from 2.54/100 000 in 2004 to 0.38/100 000 in 2020. The highest incidence rate was reported in young children aged <3 years after 2011, ranging from 1.13/100 000 to 2.78/100 000, and during this period the proportion of cases in this age group increased from 3.48% to 15.59%. The proportion of the cases in the elderly aged ≥60 years increased from 6.46% in 2004 to 19.34% in 2020. The hotspot areas existed in Yunnan, Guizhou, Guangxi and Sichuan Provinces and expanded to Guangdong, Hunan, Jiangxi, and Fujian Provinces. A total of 86 226 paratyphoid fever cases were reported from 2004 to 2020, the male to female ratio of the cases was 1.21∶1. Most cases were reported in adults aged 20-59 years (59.80%). The incidence rate of paratyphoid fever decreased from 1.26/100 000 in 2004 to 0.12/100 000 in 2020. The highest incidence rate of paratyphoid fever was in young children aged <3 years after 2007, ranging from 0.57/100 000 to 1.19/100 000, and during this period the proportion of the cases in this age group increased from 1.48% to 30.92%. The proportion of the cases in the elderly aged ≥60 years increased from 4.52% in 2004 to 22.28% in 2020. The hotspot areas expanded to the east, including Guangdong, Hunan and Jiangxi Provinces, from Yunnan, Guizhou, Sichuan, and Guangxi Provinces. Conclusions: The results showed a low level of incidence of typhoid fever and paratyphoid fever in China with a trend of decreasing per year. The hotspots were mainly in the of Yunnan, Guizhou, Guangxi and Sichuan Provinces, with an expanding trend to eastern China. It is necessary to strengthen the typhoid fever and paratyphoid fever prevention and control in southwestern China, among young children aged <3 years and the elderly aged ≥60 years.

Performance of screening of contacts of COVID-19 cases in same flight / 中华流行病学杂志

Objective: To understand the performance of 2019-nCoV nucleic acid detection in screening of contacts of COVID-19 cases in same flights and provide evidence for the effective screening of persons at high risk for the infection in domestic flights. Methods: The information of passengers who took same domestic flights with COVID-19 cases in China from April 1, 2020 to April 30, 2022 were retrospectively collected,and χ2 test was used to analyze positive nucleic acid detection rates in the passengers in different times before the onsets of the index cases, in different seat rows and in epidemic periods of different 2019-nCoV variants. Results: During the study period, a total of 433 index cases were identified among 23 548 passengers in 370 flights. Subsequently, 72 positive cases of 2019-nCoV nucleic acid were detected in the passengers, in whom 57 were accompanying persons of the index cases. Further analysis of the another 15 passengers who tested positive for the nucleic acid showed that 86.67% of them had onsets or positive detections within 3 days after the diagnosis of the index cases, and the boarding times were all within 4 days before the onsets of the index cases. The positive detection rate in the passengers who seated in first three rows before and after the index cases was 0.15% (95%CI: 0.08%-0.27%), significantly higher than in the passengers in other rows (0.04%, 95%CI: 0.02%-0.10%, P=0.007),and there was no significant difference in the positive detection rate among the passengers in each of the 3 rows before and after the index cases (P=0.577). No significant differences were found in the positive detection rate in the passengers, except the accompanying persons, among the epidemics caused by different 2019-nCoV variants (P=0.565). During the Omicron epidemic period, all the positive detections in the passengers, except the accompanying persons, were within 3 days before the onset of the index cases. Conclusions: The screening test of 2019-nCoV nucleic acid can be conducted in the passengers took the same flights within 4 days before the onsets of the index cases on board. Passengers who seated within 3 rows from the index cases can considered as the close contacts at high risk for 2019-nCoV, for whom screening should be conducted first and special managements are needed. The passengers in other rows can be classified as general risk persons for screening and management.

Epidemiological characteristics of amoebic dysentery in China, 2015-2018 / 中华流行病学杂志

To understand the characteristics and changes of the incidence of amoebic dysentery in China during 2015-2018, explore the causes of high incidence in some areas and provide a data base for the development of national prevention and control strategies and measures. Data were collected from the infectious disease reporting management information system from Chinese Disease Control and Prevention. To understand the seasonal, population and area distributions of amoebic dysentery, descriptive epidemiological method and software SPSS 16.0 were used to analyze the amoebic dysentery data. A total of 4 366 amoebic dysentery cases were reported without death in China during 2015-2018. The reported average annual incidence was 0.08/100 000, and the overall proportion of laboratory confirmed cases was 68.23(2 979/4 366). Amoeba dysentery mainly occurred during May to October. One seasonal peak was observed in 2015 and 2017 (July and June, respectively), and two seasonal peaks were observed in 2016 and 2018 (June and October). The patients were mainly children aged under 5 years (42.28, 1 846/4 366), and the incidence rate decreased with age in children aged under 10 years. Of these, children under 1 years of age had the highest incidence rate (1.28/100 000). The number of cumulative reported cases in Guangxi, Henan, Guangdong, Heilongjiang and Jiangxi provinces ranked top five from 2015-2018, accounting for 64.50 (2 816/4 366) of the total. The cumulative cases in Dongxing county, Guangxi, in Suixian county, Henan and in Ranghulu district, Heilongjiang, respectively accounted for more than 50.00 of the total number of cases in their provinces. The incidence rate of amoebic dysentery reported in China during 2015-2018 showed a decreasing trend, with a higher incidence in children under 5 years old and a higher number of cases in some areas. It is suggested to further investigate and analyze the diagnosis and reporting of amoeba dysentery in key areas and promote the update of the diagnostic standards for amoeba dysentery.

Dynamics of Rodent and Rodent-borne Disease during Construction of the Three Gorges Reservoir from 1997 to 2012 / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>The average indoor and outdoor rodent densities decreased overall from 1997 to 2012. The average densities decreased by 47.72% (from 4.38% to 2.29%) and 39.68% (from 4.41% to 2.66%), respectively, after impoundment (2003-2012) compared with before impoundment (1997-2002). The average annual incidence rates of HFRS and leptospirosis were 0.29/100,000 and 0.52/100,000, respectively, and decreased by 85.74% (from 0.68/100,000 to 0.10/100,000) and 95.73% (from 1.47/100,000 to 0.065/100,000), respectively, after impoundment compared with before impoundment. Incidences of HFRS and leptospirosis appear to be positively correlated with rodent density in the reservoir area.</p><p><b>CONCLUSION</b>This study demonstrated that rodent density and incidences of rodent-borne diseases decreased and were maintained at low levels during construction of the Three Gorges dam. Measures that reduce rodent population densities could be effective in controlling rodent-borne diseases during large-scale hydraulic engineering construction.</p>

Epidemiological features of typhoid/paratyphoid fever in provinces with high incidence rate and in the whole country, in 2012 / 中华流行病学杂志

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.The incidence rate was 0.89 per 100 000.Compared to the data gathered in 2011,the incidence rates of typhoid/paratyphoid fever increased by 1.20％.The total number of the confirmed cases on typhoid and paratyphoid fever was 6522 and was accounted for 54.36％ of the total cases,in which paratyphoid fever accounted for 36.86％.Cases were mainly involved farmers and followed by students and children.Incidence rates of typhoid and paratyphoid fever in children aged 0-4 years old appeared the highest (respectively 1.31/100 000 and 0.46/100 000).Yunnan,Guizhou,Guangdong,Guangxi,Zhejiang,Hunan and Xinjiang provinces (autonomous regions) were identified as provinces with high-incidence rates of typhoid and paratyphoid fever.During 2005-2012,the incidence rates in most of the above high-incidence provinces showed a downward trend,except for in Guangdong which had only showed a slight change.There were variations on peak period and highly-hit population in seven high-incidence provinces.Conclusion The incidence rate of typhoid/paratyphoid fever was in a relatively low level in China.Prevention and control strategies on the diseases in children under 5 years old remained a challenge,warranted more work to be done.The epidemiological situation is still severe in some high-incidence rate provinces.

Epidemiological features of hand,foot and mouth disease in China,2008-2009 / 中华流行病学杂志

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 epidemical 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 1155525 reported HFMD cases in 2008 and 2009,in China,of which 1165 and 13810 were severe and 126 and 353 were fatal,respectively.The notification rates were 50.09/10 million,68.47/10 million and 59.04/10 million in high,medium and low latitudes areas,respectively.The epidemic periods in Medium and Low latitude were from 12 to 24 weeks in 2009,and in high latitude it was from 23 to 35 weeks.HFMD cases were concentrated mainly in 5 year-old or even younger children,accounted for 92.23% of the total cases.The incidence rate of two years old appeared to be the highest.The features of severe and death case concentrated in lower age groups were more evident,and the proportion of severe case and case fatality rate under 1 vears old was higher than that in other age groups.We also noticed that with the increasing of age,the proportion of severe case and case fatality rate had a decreasing trend.There was a difference between the pathogens seen.The relative risk(RR)for an human enterovirus 71(HEV71)isolate was higher among severe case than in common cases(RR=1.82),whereas the RR for an EV71 isolate was higher among the death cases than in common cases (RR=2.11).There was seasonal variation of pathogen composition.There were 477 clusters of cases from 2008 to 2009,of which 389 found in preschools,47 in rural villages,outbreaks of clusters were mainly from April to July. Conclusion The HFMD epidemics was increasing in 2009.The epidemic of HFMD in different latitudes area and seasons was different.Children of five year old or under were the major population groups at risk,of HFMD.The younger ones had higher risk of becoming severe and death cases.HEV71 and coxsackievirus A16 were both the major etiologic agents of HFMD.The preschool and rural villages were the main senings of clusters of cases.

Surveillance on the health status regarding vector-borne disease among people living in the three gorges reservoir area (1997-2009) / 中华流行病学杂志

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.Methods related to time and spatial analysis and the comparison on pre- and post- water storage were used to analyze and describe the long-term changing trend of meteorological index,distribution of biological agent and diseases,and human health status.Relationships between number of infectious diseases and media biological density and meteorological parameters were also analyzed.Results When the water storage program came into being in 2003,the indoor (2.22％) and outdoor (2.76％) densities of rats were significantly lower than pre-water storage period (indoor 4.38％ vs.outdoor 4.43％) and the annual average density of mosquito (35.09 mosquitoes per room and per hour) was also lower than before (54.24 mosquitoes per room and per hour).The incidence rates of encephalitis B,malaria,leptospirosis,and hemorrhagic fever had reduces 22.88％,84.85％,95.03％ and 81.82％ than before.The incidence rates of malaria,leptospirosis,and hemorrhagic fever were all below 0.4/100 000 and the incidence of encephalitis B was below 2/100 000.The average infant mortality was 11.83‰.The annual infant mortalities,after adjusted by missing report numbers,were between 13.07‰ and 23.88‰ which were lower than the national annual average level.The thirteen year standard mortalities were 3.77‰-5.12‰,with the total rate lower than the national average level in the same years.Conclusion In 2003,the incidence rates of malaria,encephalitis B,leptospirosis,epidemic hemorrhagic fever kept going down in the surveillance sites in the Three Gorges Reservoir Area,and the overall population's health status was well enough to show that there was no negative impact on the health status of population living in the area after the water storage project was inplemented.

Analysis on bacillary dysentery surveillance data collected from the National Surveillance System in 2007 / 中华流行病学杂志

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. Results Data from the monitoring sites showed that the detection rate of infant cases of bacillary dysentery infection was 1%,less than that of other age groups. The highest rates were seen in children aged 3 through 9 years. Rate on misdiagnosis in all age group was 23.38%,when using the surveillance case definition of clinical cases and suspect case. The rate of misdiagnosis on infant cases of bacillary dysentery infection by clinical diagnosis was 50%. It showed that Shigella flexneri and Shigella sonnei were dominant with the positive rates as 57.21% and 42.41%,respectively. From the national sentinel surveillance sites,the confirmed cases taking up 43.39% which did not match the figure from the CDRIS. Conclusion The diagnostic criterion for bacillary dysentery fit well on other age groups in surveillance system except on infants. Active surveillance on bacillary dysentery that combining both clinical and laboratory diagnosis seems quite necessary on CDRIS,especially for infants.

Outbreaks of noroviral gastroenteritis and their molecular characteristics in China, 2006 -2007 / 中华流行病学杂志

Objective To acknowledge the epidemiology of gastroenteritis outbreaks caused by norobiruses 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. Sequence alignment and phylogenetic analysis were performed by Clustal X 1.83 and MEGA 4.0 programs.Results Noroviruses were one of the most predominant pathogens causing viral gastroenteritis outbreaks ( 12 of 19 outbreaks, accounting for 63.2% ). Variant G Ⅱ -4/2006b was the predominant strain responsible for 11 of the 12 NV-associated outbreaks. Other genotypes would include G Ⅱ -17,G Ⅱ -6 and G Ⅱ -3. The NV-associated gastrocnteritis outbreaks occurred mainly in winter and spring between December 2006 and April 2007. These gastroenteritis outbreaks caused by noroviruses would involve all age groups in various locations. Meantime, 2 out of 12 outbreaks were caused by norovirus or other viruses. In addition, multiple viruses and multiple genotypes of noroviruses were found in the same outbreak. Conclusion Noroviruses were one of the most major pathogens causing gastroenteritis outbreaks while G Ⅱ -4/2006b variant was identified as the predominant strain in China.

Analysis of epidemiologic feature and genetic sequence of Sapovirus in China / 病毒学报

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 (0.9%) were positive for Sapovirus. The PCR products were then sequenced and analysed by phylogenetic tree. The results indicated that the detected Sapovirus strains were classified into two genogroups and three genotypes, including G I/1, G I/3, G II/3.

Study on the health status and affecting factors among people living in the surveillance sites of Three Gorges Reservoir Areas. in 2007 / 中华流行病学杂志

Objective To understand the health status and potential impact resulted in the second stage of Three Gorges Reservoir Areas sluicing. Methods Data were collected on deaths, prevalence rates of infectious and endemic diseases, as well as on vector surveillance through the project entitled 'Three Gorges Population Health Survey System'. Results The main causes of death in the population living in the Three Gorges Reservoir Areas would include: circulatory system diseases, tumors, respiratory system diseases, injuries/poison and digestive system diseases. The number of deaths caused by the above said five kind of diseases accounted for 90.94% of the total number of deaths. The prevalence rates on Water-born diseases related to the sluicing of reservoir and zoonosis-bome diseases related to the changes of vectors were still low. The indoor and outdoor densities of rodents were 3.11% and 3.16%, both were higher than that in 2006 but lower than the average numbers in the five years prior to the sluicing. The constituent ratio of Apodemus agrarius had constantly risen since 2006. The density of mosquitoes found in livestock barns and human households was higher than that in 2006 but lower than the average number of the five-year studies prior to the sluicing. Conclusion Environment change after the sluicing of the Three Gorges Reservoir Areas did not seem to have obvious impact on the health status of the people living in the areas. However, to strengthen the surveillance on the biological features of the vectors which might have related to the transmission of diseases would be highly recommended.

Analysis on the status of Shigella spp antimicrobial resistance through data from the National Shigellosis Surveillance System in China, in 2005 / 中华流行病学杂志

<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>All the lab assistants received training from Chinese Center for Disease Control and Prevention. The project prescribed the uniform experimentation, quality control method, reagent, etc. Disc diffusion test(K-B) was carried out, following the CLSI methods. Data were analyzed by WHONET 5.4 software.</p><p><b>RESULTS</b>(1) 3 serotypes were identified and S. flexneri was common that accounted for 75.5% of all Shigella isolates followed by 24.4% of S. sonnei, but only 1 strain of S. dysenteriae was separated. (2) The resistant rates to tetracycline and ampicillin in Shigella spp were quite high, as over 90.0%. However, the resistant rate to Cefotaxime was the lowest, only 6.1%. The resistant rates were different between serotypes with the resistant rates of S. flexneri to ampicillin, ampicillin/clavulanate and ciprofloxacin were higher than those of S. sonnei (P < 0.001). (3) The multiple-antibiotic-resistance status in Shigella spp was quite serious and the resistant rate to five and more antimicrobials was 54.9%. The most common resistant patterns were seen on ampicillin, nalidixin, tetracycline and sulfamethoxazole. (4) There were some differences in subtypes and antimicrobial resistance among different provinces.</p><p><b>CONCLUSION</b>Cefotaxime seemed the best in curing Shigellosis at the clinic level. Programs regarding monitoring subtypes and antimicrobial resistance of Shigella should be in a continuous manner so as to understand the pathogens timely and to control the disease pertinently.</p>

Investigation on status of pollution of vibrio cholera in seafood and aquatic products in 12 provinces of China in 2005 / 中华预防医学杂志

<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>Different seafood, aquatic products and breed water specimen collected from 12 provinces of China were tested from July to September in 2005.</p><p><b>RESULT</b>A total of 12 104 samples of seafood and aquatic products were tested and the average pollution rate of vibrio cholera was 0.52%. The positive isolate rate of turtle sample (1.72%) was the highest among all samples. The second higher isolated rate was 1.14% in water specimen of turtle breed pool. The positive rate of bullfrog was 0.50%. The percentage of toxin strains was 47.54% and 79.31% of them were isolated from turtle and water samples of turtle breed pool. The important sector of the pollution of vibrio cholera was in turtle breed pool (2.38%).</p><p><b>CONCLUSION</b>The average pollution rate of vibrio cholera in seafood and aquatic products in 12 provinces of China was low. It should be very necessary to supervise the sanitation in turtle breed for controlling and preventing the vibrio cholera.</p>

Identification and molecular study on vibrio cholerae in sea products / 中华预防医学杂志

<p><b>OBJECTIVE</b>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.</p><p><b>METHOD</b>The biotype of strains isolated was analyzed by using type and phage-biotype serological methods. The toxic gene was detected by PCR.</p><p><b>RESULTS</b>The constituent ratio of V. cholerae O139, Ogawa and Inaba were, respectively, 48.44%, 20.31% and 31.25% in 64 strains of V. cholerae. The result of phage-biotype showed that the 26 strains of V. cholerae O1 were all non-epidemic strains. The result of toxic gene detecting showed that positive rate of V. cholerae O139 was higher than those of Ogawa and Inaba.</p><p><b>CONCLUSION</b>The positive rate of toxic gene in V. cholerae O139 was high and the V. cholerae O139 was mainly in turtle, breed aquatics water and crustacean, so these sea products were the important sectors in cholera prevention and control.</p>

Study on the RNA of severe acute respiratory syndrome (SARS) associated coronavirus in the blood and excretion of convalescent patients with SARS / 中华流行病学杂志

<p><b>OBJECTIVE</b>To examine the RNA of severe acute respiratory syndrome-associated coronavirus (SARS-CoV) in the blood and excretion of convalescent patient with SARS for prevention and treatment of the disease.</p><p><b>METHODS</b>A total of 276 samples, including plasma, urine, feces and sputum, obtained from 23 convalescent patients with SARS were studied at 3 time-points at least 21 days after the onset of symptoms. RNA was extracted and nested reverse transcription-polymerase chain reaction (RT-PCR) was carried out using SARS-CoV specific primers.</p><p><b>RESULTS</b>Among the 276 samples, SARS-CoV RNA was detected in 6 cases (38.8%) by nested RT-PCR. The positive rates of SARS-CoV RNA was 5.8% in feces and 2.9% in sputum samples but SARS-CoV RNA was not detectable in plasma and urine of all the cases.</p><p><b>CONCLUSION</b>The existence of SARS-CoV RNA in the excretion of some convalescent patients with SARS showed that the excretion from these patients should be carefully treated whilthe re-transmission of SARS by which, should be further studied.</p>

Preparation and characterization of monoclonal antibodies against SARS-associated coronavirus nucleocapsid protein / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>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. The specificity of the McAbs obtained was examined by Western blot and indirect fluorescence assay. Epitopes reacted with the McAbs were preliminarily located through Western blot by expressing truncated N proteins.</p><p><b>RESULTS</b>After cell fusion and three rounds of cell cloning, six hybridoma cell lines secreting monoclonal antibodies specifically against SARS-CoV nucleocapsid were obtained. Western blot and indirect fluorescence assay showed that the McAbs reacted specifically with nucleocapsid protein and SARS-CoV. Among the six McAbs, three recognize the epitopes located in the N-terminus of the protein, whereas the others reacted with those located in the C-terminus.</p><p><b>CONCLUSION</b>The anti-SARS-CoV nucleocapsid McAbs were developed and these McAbs may be useful in the development of diagnosis assays and basic research of SARS.</p>