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Hu et al. show that sumoylation of the viral RNA sensors RIG-I and MDA5 by TRIM38 in uninfected and early-infected cells, and their desumoylation by SENP2 in the late phase of infection, ensure efficient innate immune responses to RNA viruses and their timely termination upon resolution of infection., Sensing of viral RNA by the cytosolic receptors RIG-I and melanoma differentiation-associated gene 5 (MDA5) leads to innate antiviral response. How RIG-I and MDA5 are dynamically regulated in innate antiviral response is not well understood. Here, we show that TRIM38 positively regulates MDA5- and RIG-I–mediated induction of downstream genes and acts as a SUMO E3 ligase for their dynamic sumoylation at K43/K865 and K96/K888, respectively, before and after viral infection. The sumoylation of MDA5 and RIG-I suppresses their K48-linked polyubiquitination and degradation in uninfected or early-infected cells. Sumoylation of the caspase recruitment domains of MDA5 and RIG-I is also required for their dephosphorylation by PP1 and activation upon viral infection. At the late phase of viral infection, both MDA5 and RIG-I are desumoylated by SENP2, resulting in their K48-linked polyubiquitination and degradation. These findings suggest that dynamic sumoylation and desumoylation of MDA5 and RIG-I modulate efficient innate immunity to RNA virus and its timely termination.

Objective Since July 1, 2011 antiviral therapy for hepatitis B virus infection has been listed as a reimbursable expense for medical insurance in Beijing. This study aimed to assess the impact of this program on liver-related death for patients with chronic hepatitis B (CHB). Methods Profiles of patients with CHB discharged between January 2008 and December 2015 were retrieved from the Beijing hospital discharge database. Liver-related deaths in these patients occurring between January 2008 and December 2017 were retrieved by linking them to the death certification database. Liver-related mortality (number of deaths divided by the observed person-years) before and after this program was launched was calculated and compared. A Poisson regression was performed to assess the strength of association (risk ratio [RR]) between the reimbursement program and liver-related mortality. Results Information on 35 943 discharged patients (17 114 patients with non-cirrhotic and 18 829 with compensated cirrhotic CHB) was retrieved. Altogether 3 832 liver-related deaths during the 190 695 person-years were observed. After the reimbursement program was launched, liver-related mortality per 100 person-years dropped from 0.38% to 0.16% for patients with non-cirrhotic CHB, and from 4.03% to 3.39% for those with compensated cirrhosis. The program was associated with a lower risk of developing liver-related death for patients with non-cirrhotic CHB (RR 0.40, 95% confidence interval [CI] 0.30-0.52) and those with compensated cirrhosis (RR 0.84, 95% CI 0.78-0.89). Conclusion Coverage of antiviral therapy by basic medical insurance reduced the risk of developing liver-related death for patients with non-cirrhotic and with compensated cirrhotic CHB.

During viral infection, sensing of cytosolic DNA by the cyclic GMP-AMP synthase (cGAS) activates the adaptor protein STING and triggers an antiviral response. Little is known about the mechanisms that determine the kinetics of activation and deactivation of the cGAS-STING pathway, ensuring effective but controlled innate antiviral responses. Here we found that the ubiquitin ligase Trim38 targets cGas for sumoylation in uninfected cells and during the early phase of viral infection. Sumoylation of cGas prevented its polyubiquitination and degradation. Trim38 also sumoylated Sting during the early phase of viral infection, promoting both Sting activation and protein stability. In the late phase of infection, cGas and Sting were desumoylated by Senp2 and subsequently degraded via proteasomal and chaperone-mediated autophagy pathways, respectively. Our findings reveal an essential role for Trim38 in the innate immune response to DNA virus and provide insight into the mechanisms that ensure optimal activation and deactivation of the cGAS-STING pathway.

The current paper presents an outdoor monitoring system for elderly people, which can transmit information on physiological signals and falling events to a healthcare center at any time and from any place. To detect simultaneously the occurrence of any falling event, as well as the relative electrocardiogram (ECG) signal of the user, a multi-thread method is proposed with the objective of enhancing the response time and the accuracy of detection. A healthcare box is used to determine the relative position of the patient through a global positioning system for fall detection; moreover, an ECG signal acquisition thread is adopted to increase the precision of the fall detection system. Integrating a precise map into the monitoring system facilitates understanding of a client user of the correct location and surrounding environment using the portable display. According to experimental results based on 4,000 samples, successful detection time with the multi-thread method was reduced by 38%, thereby increasing rescue opportunities for elderly patients who are at risk1.

Tripartite motif (TRIM)38 is an E3 ubiquitin ligase that was reported to regulate signaling in innate immune and inflammatory responses in certain cell lines. In this study, we show that Trim38 deficiency markedly increased TLR3- and TLR4-mediated induction of type I IFNs and proinflammatory cytokines, such as TNF-α, IL-1β, and IL-6, in immune cells and in vivo. Trim38 deficiency also caused the mice to be more susceptible to death triggered by polyinosinic-polycytidylic acid, LPS, and Salmonella typhimurium. Mechanistically, TRIM38 catalyzed K48-linked polyubiquitination of the TLR3/4 adapter protein TIR domain–containing adapter-inducing IFN-β at K228 and promoted its proteasomal degradation in immune cells. Moreover, Trim38 was highly induced by type I IFNs, which then negatively regulated TNF-α/IL-1β signaling in IFN-β–primed immune cells, but not unprimed immune cells, by mediating degradation of Tab2 in a lysosomal-dependent process. These results suggest that Trim38 negatively regulates TLR3/4-mediated innate immune and inflammatory responses by two sequential and distinct mechanisms. This study increases our understanding of how the innate immune response is initiated during the early phase of infection to defend against microbial invasion and is efficiently terminated during the late phase to prevent excessive and harmful inflammatory responses.

Autophagy is a highly conserved process, representing the major eukaryotic degradative pathway of cellular components. Autophagy-mediated recycling of cellular materials contributes to cell differentiation, tissue remodelling and proper development. In fungi, autophagy is required for normal growth and cell differentiation. The entomopathogenic fungus Beauveria bassiana and its invertebrate targets represent a unique model system with which to examine host-pathogen interactions. The ATG5 gene is one of 17 involved in autophagosome formation, and the B. bassiana homologue (BbATG5) was identified. The role of autophagy in B. bassiana growth and virulence was investigated via construction of a targeted gene knockout of BbATG5. The mutant strain displayed increased sensitivity to nutrient limitation, with decreased germination and growth as compared with the wild-type parent. Conidiation was severely compromised and conidia derived from the ΔBbATG5 strain were altered in morphology. Cell differentiation into blastospores was also greatly reduced. Despite the significant growth and developmental defects, insect bioassays using the oriental leafworm moth, Spodoptera litura, indicated a modest (~40 %) decrease in virulence in the ΔBbATG5 strain. The phenotypic defects of the ΔBbATG5 strain could be restored by introduction of an intact copy of BbATG5. These data suggest that unlike several plant and animal pathogenic fungi, where ATG5 is required for infection, in B. bassiana it is dispensable for pathogenesis.

Ras1 and Ras2 are two distinct Ras GTPases in Beauveria bassiana, an entomopathogenic fungus whose biocontrol potential against insect pests depends largely on virulence and multi-stress tolerance. The functions of both proteins were characterized for the first time by constructing dominant-active (GTP-bound) Ras1(G19V) and dominant-negative (GDP-bound) Ras1(D126A) and integrating them and normal Ras1 into wild type and ΔRas2 for a series of phenotypic and transcriptional analyses. The resultant mutants showed gradient changes of multiple phenotypes but little difference in conidial thermotolerance. Expression of Ras1(D126A) caused vigorous hyphal growth, severely defective conidiation, and increased tolerances to oxidation, cell wall disturbance, fungicide and UV-A/UV-B irradiations, but affected slightly germination, osmosensitivity and virulence. These phenotypes were antagonistically altered by mRas1(G19V) expressed in either wild type or ΔRas2, which was severely defective in conidial germination and hyphal growth and displayed intermediate changes in other mentioned phenotypes between paired mutants expressing Ras1(G19V) or Ras1(D126A) in wild type and ΔRas2. Their growth, UV tolerance or virulence was significantly correlated with cellular response to oxidation or cell wall disturbance. Transcriptional changes of 35 downstream effector genes involved in conidiation and multi-stress responses also related to most of the phenotypic changes among the mutants. Our findings highlight that Ras1 and Ras2 regulate differentially or antagonistically the germination, growth, conidiation, multi-stress tolerance and virulence of B. bassiana, thereby exerting profound effects on the fungal biocontrol potential.

This paper presents an electrocardiogram (ECG) feature extraction with wavelet algorithm for personal healthcare monitoring. Developing a wireless ECG examination system employed to monitor the cardiovascular disease (CVD) is signification, especially uses a low-power device anywhere and anytime detecting the real-time ECG signal for self-examination applications. The continuous time Mexican-Hat wavelet transform (CTMHWT) algorithm is quickly and easily applied to analyze the approximation of P-QRS-T complex fiducial points. The database, MIT-BIH discrete points, is adopted to efficiently extract the ECG signal according to CTMHWT algorithm with Matlab simulator. Moreover, the simulation result reveals that the feature extraction of ECG signal is satisfied to the required error range.

Background With market-oriented economic and health-care reform, public hospitals in China have received unprecedented pressures from governmental regulations, public opinions, and financial demands. To adapt the changing environment and keep pace of modernizing healthcare delivery system, public hospitals in China are expanding clinical services and improving delivery efficiency, while controlling costs. Recent experiences are valuable lessons for guiding future healthcare reform. Here we carefully study three teaching hospitals, to exemplify their experiences during this period. Methods We performed a systematic analysis on hospitalization costs, health-care quality and delivery efficiencies from 2006 to 2010 in three teaching hospitals in Beijing, China. The analysis measured temporal changes of inpatient cost per stay (CPS), cost per day (CPD), inpatient mortality rate (IMR), and length of stay (LOS), using a generalized additive model. Findings There were 651,559 hospitalizations during the period analyzed. Averaged CPS was stable over time, while averaged CPD steadily increased by 41.7% (P

To survey the incidence of acute coronary events and its trend in three years, and explore the distribution of the incidence across Beijing residents aged 25 years and more from 2007 to 2009.The present study incorporated and linked the routinely collected data from the Hospital Discharge Information System and Cause of Death Register System in Beijing, estimated the incidence of acute coronary events, and analyzed the distribution of the incidence across gender, age groups and regions. Acute coronary event was defined as non-fatal myocardial infarction and death from coronary heart disease. Numbers of residents by age, gender and area were obtained from the Beijing Statistics Bureau.A total of 68 390 acute coronary events were identified among permanent residents of Beijing aged 25 years and more from 2007 to 2009. The age-standardized incidence was 166.4 per 100 000 people in overall population, with 218.5 in males and 115.2 in females. The age-standardized incidence was 144.3, 154.7, and 195.8 per 100 000 people in urban, suburban, and exurban area, respectively. The incidence was the highest in Huairou district (263.8 per 100 000), while was the lowest in Haidian district (121.5 per 100 000). The age-standardized incidence was 158.4, 169.4, and 171.2 per 100 000 in 2007, 2008, and 2009, respectively. The age-standardized incidence increased by 8.1% in 2009 compared to 2007, increase in men (11.1%) was greater than in women (2.5%). The incidence increased significantly with age in each year. The incidence raised by 30.3% in 2009 compared to 2007 for men aged 35 - 44 years. In 2009, the incidence was 146.7, 155.9, and 207.4 per 100 000 people in urban, suburban, and exurban area, respectively. The rates increased by 3.2% in both urban and suburban areas, and 16.4% in exurban areas in 2009 compared to 2007.The incidence of acute coronary events increased from 2007 to 2009 among the permanent residents of Beijing aged 25 years and over, especially in young men, and people living in the exurban areas.

To examine the distribution and trends of hospitalization rates for coronary heart disease (CHD) from 2007 to 2009 in Beijing.We calculated hospitalization rates for CHD using data from Beijing Hospital Discharge Information System. Information of census registered population in Beijing was obtained from Beijing Municipal Bureau of Statistics. CHD includes acute myocardial infarction, unstable angina and other forms of CHD. Age-standardized hospitalization rates for CHD per 100 000 population aged 25 years or more were calculated.During 2007 - 2009, a total of 248 049 patients aged 25 years or more hospitalized in Beijing with the primary discharge diagnosis of CHD were enrolled, of whom 73.7% were permanent registered Beijing citizens. The average hospitalization rate for CHD in 2007 - 2009 was 651.2/100 000 for the permanent residences in Beijing (741.2/100 000 in men, 560.9/100 000 in women). The highest average hospitalization rate (671.9/100 000) was seen in exurban area compared to other areas in Beijing. The average hospitalization rate for acute myocardial infarction, unstable angina, and other CHD was 126.4/100 000, 226.4/100 000 and 298.4/100 000, respectively. The hospitalization rate for CHD increased 18.1% from 2007 to 2009 (from 598.1/100 000 to 706.5/100 000). The same trend was seen in women (20.2%) and men (16.6%). The hospitalization rates of CHD in the urban, suburban, and exurban areas of Beijing all increased in the three years, and the greatest increase (36.6%) was found in exurban area. Hospitalization rates of acute myocardial infarction and unstable angina increased 24.5% and 55.3%, respectively, in the three years, while hospitalization rates of other CHD decreased 5.7%.The hospitalization rate of CHD is higher in men than in women in Beijing. The hospitalization rates for CHD increased from the observation period, especially in those living in exurban area. Awareness of the magnitudes and trends of CHD hospitalization rates is of great importance in evaluating the burden of cardiovascular disease, allocating and utilizing health care resources, and estimating the health insurance for Beijing.

The ascomycete fungus Beauveria bassiana is a pathogen of hundreds of insect species and is commercially produced as an environmentally friendly mycoinsecticide. We sequenced the genome of B. bassiana and a phylogenomic analysis confirmed that ascomycete entomopathogenicity is polyphyletic, but also revealed convergent evolution to insect pathogenicity. We also found many species-specific virulence genes and gene family expansions and contractions that correlate with host ranges and pathogenic strategies. These include B. bassiana having many more bacterial-like toxins (suggesting an unsuspected potential for oral toxicity) and effector-type proteins. The genome also revealed that B. bassiana resembles the closely related Cordyceps militaris in being heterothallic, although its sexual stage is rarely observed. A high throughput RNA-seq transcriptomic analysis revealed that B. bassiana could sense and adapt to different environmental niches by activating well-defined gene sets. The information from this study will facilitate further development of B. bassiana as a cost-effective mycoinsecticide.

The biocontrol potential of entomopathogenic fungi against arthropod pests depends on not only their virulence to target pests but tolerance to outdoor high temperature and solar UV irradiation. Two Beauveria bassiana superoxide dismutases (SODs), BbSod2 and BbSod3, were characterized as cytosolic and mitochondrial manganese-cored isoenzymes (MnSODs) dominating the total SOD activity of the fungal entomopathogen under normal growth conditions. To probe their effects on the biocontrol potential of B. bassiana, ΔBbSod2, ΔBbSod3, and three hairpin RNA-interfered (RNAi) mutants with the transcripts of both BbSod2 and BbSod3 being suppressed by 91-97% were constructed and assayed for various phenotypic parameters in conjunction with ΔBbSod2/BbSod2, ΔBbSod3/BbSod3 and wild-type (control strains). In normal cultures, the knockout and RNAi mutants showed significant phenotypic alterations, including delayed sporulation, reduced conidial yields, and impaired conidial quality, but little change in colony morphology. Their mycelia or conidia became much more sensitive to menadione or H(2)O(2)-induced oxidative stress but had little change in sensitivity to the hyperosmolarity of NaCl and the high temperature of 45°C. Accompanied with the decreased antioxidative capability, conidial tolerances to UV-A and UV-B irradiations were reduced by 16.8% and 45.4% for ΔBbSod2, 18.7% and 44.7% for ΔBbSod3, and ∼33.7% and ∼63.8% for the RNAi mutants, respectively. Their median lethal times (LT(50)s) against Myzus persicae apterae, which were topically inoculated under a standardized spray, were delayed by 18.8%, 14.5% and 37.1%, respectively. Remarkably, the effects of cytosolic BbSod2 and mitochondrial BbSod3 on the phenotypic parameters important for the fungal bioncontrol potential were additive, well in accordance with the decreased SOD activities and the increased superoxide levels in the knockout and RNAi mutants. Our findings highlight for the first time that the two MnSODs co-contribute to the biocontrol potential of B. bassiana by mediating cellular antioxidative response.

Metarhizium spp. are being used as environmentally friendly alternatives to chemical insecticides, as model systems for studying insect-fungus interactions, and as a resource of genes for biotechnology. We present a comparative analysis of the genome sequences of the broad-spectrum insect pathogen Metarhizium anisopliae and the acridid-specific M. acridum. Whole-genome analyses indicate that the genome structures of these two species are highly syntenic and suggest that the genus Metarhizium evolved from plant endophytes or pathogens. Both M. anisopliae and M. acridum have a strikingly larger proportion of genes encoding secreted proteins than other fungi, while ∼30% of these have no functionally characterized homologs, suggesting hitherto unsuspected interactions between fungal pathogens and insects. The analysis of transposase genes provided evidence of repeat-induced point mutations occurring in M. acridum but not in M. anisopliae. With the help of pathogen-host interaction gene database, ∼16% of Metarhizium genes were identified that are similar to experimentally verified genes involved in pathogenicity in other fungi, particularly plant pathogens. However, relative to M. acridum, M. anisopliae has evolved with many expanded gene families of proteases, chitinases, cytochrome P450s, polyketide synthases, and nonribosomal peptide synthetases for cuticle-degradation, detoxification, and toxin biosynthesis that may facilitate its ability to adapt to heterogenous environments. Transcriptional analysis of both fungi during early infection processes provided further insights into the genes and pathways involved in infectivity and specificity. Of particular note, M. acridum transcribed distinct G-protein coupled receptors on cuticles from locusts (the natural hosts) and cockroaches, whereas M. anisopliae transcribed the same receptor on both hosts. This study will facilitate the identification of virulence genes and the development of improved biocontrol strains with customized properties., Author Summary Aside from playing a crucial role in natural ecosystems, entomopathogenic fungi are being developed as environmentally friendly alternatives for the control of insect pests. We conducted the first genomic study of two of the best characterized entomopathogens, Metarhizium anisopliae and M. acridum. M. anisopliae is a ubiquitous pathogen of >200 insect species and a plant growth promoting colonizer of rhizospheres. M. acridum is a specific pathogen of locusts. Important findings of this study included: 1) Both M. anisopliae and M. acridum have a very large number of genes encoding secreted proteins, and many of these play roles in fungus-insect interactions. 2) M. anisopliae has more genes than M. acridum, which may be associated with adaptation to multiple insect hosts. 3) Unlike M. acridum, the M. anisopliae genome contains many more transposase genes and shows no evidence of repeat-induced point mutations. The lack of repeat-induced mutations may have allowed the lineage-specific gene duplications that have contributed to its adaptability. 4) High-throughput transcriptomics identified the strategies by which these fungi overcome their insect hosts and achieve specificity. These genome sequences will provide the basis for a comprehensive understanding of fungal–plant–insect interactions and will contribute to our understanding of fungal evolution and ecology.

A superoxide dismutase (SOD) was characterized from Beauveria bassiana, a fungal entomopathogen widely applied to insect control. This 209-aa enzyme (BbSod2) showed no more than 71% sequence identity to other fungal Mn-SODs, sharing all conserved residues with the Mn-SOD family and lacking a mitochondrial signal. The SOD activity of purified BbSod2 was significantly elevated by Mn(2+), suppressed by Cu(2+) and Zn(2+) but inhibited by Fe(3+). Overexpressing the enzyme in a BbSod2-absent B. bassiana strain enhanced its SOD activity (107.2 +/- 6.1 U mg(-1) protein) by 4-10-fold in different transformants analyzed. The best BbSod2-transformed strain with the SOD activity of 1,157.9 +/- 74.7 U mg(-1) was 93% and 61% more tolerant to superoxide-generating menadione in both colony growth (EC(50) = 2.41 +/- 0.03 versus 1.25 +/- 0.01 mM) and conidial germination (EC(50) = 0.89 +/- 0.06 versus 0.55 +/- 0.07 mM), and 23% more tolerant to UV-B irradiation (LD(50) = 0.49 +/- 0.02 versus 0.39 +/- 0.01 J cm(-2)). Its virulence to Spodoptera litura larvae was enhanced by 26% [LT(50) = 4.5 (4.2-4.8) versus 5.7 (5.2-6.4) days]. Our study highlights for the first time that the Mn(2+)-cofactored, cytosolic BbSod2 contributes significantly to the virulence and stress tolerance of B. bassiana and reveals possible means to improving field persistence and efficacy of a fungal formulation by manipulating the antioxidant enzymes of a candidate strain.

To evaluate the quality of the infectious diseases reporting via network in Beijing hospitals and to filtrate factors that affect the reporting quality.We collected 5536 infectious disease cases randomly and investigated 52 medical treatment organizations. Information was collected by field questionnaire survey, interview and gathering routine reporting data for analyzing the quality.The result showed that the timeliness of the 52 medical treatment organizations was 94.18%, the consistency was 80.84%, the completeness was 88.47%, and the misreport was 13.73%. The reporting quality of the second level hospitals was higher than that of the first level hospitals, township health centers and the third level hospitals. The reporting quality of urban hospitals was higher than that of the suburb hospitals. The reporting quality of outpatient and inpatient departments was higher than that of the laboratory. The laboratory was the primary part of underreporting.Strengthening guidance, training and paying attention to each weak portion would certainly ameliorate the quality of infectious diseases reporting via network.

To summarize lessons learned from an outbreak of severe acute respiratory syndrome (SARS) in China during the spring of 2004.Data of SARS cases were officially reported by Beijing Municipal Center for Disease Control and Prevention (BCDC) and Anhui Provincial Center for Disease Control and Prevention (APCDC) and results of epidemiological investigations were collected and analyzed.Three generations of 11 cases of SARS were identified during the outbreak. Initial two cases were most likely to be infected in Diarrhea Virus Laboratory of National Institute of Virology, China Centers for Disease Control and Prevention and main mode of transmission was direct contact with SARS patients. Delay in detecting initial case resulted in spread of the illness at hospitals and communities with two generations of secondary cases.SARS outbreak in 2004 has yielded following lessons for public health globally. (1) Lab bio-safety programs should be made and should be strictly abided by. Studies in highly pathogenic viruses such as SARS coronavirus should be utmost cautious. (2) Management systems of occupational exposure to virus and disease surveillance need to be strengthened to take all risk factors into account so as to detect potential patients with infectious disease as early as possible.

To study the potential risk factors for severe acute respiratory syndromes (SARS)-related deaths in Beijing.Epidemiological data were collected among the confirmed SARS patients officially reported by Beijing Centers for Disease Control and Prevention (BCDC), and information was also supplemented by a follow-up case survey. Chi-square test and multivariate stepwise logistic regression analysis were performed.Old age (over 60 years) was found to be significantly associated with SARS-related deaths in the univariate analysis. Also, history of contacting SARS patients within 2 weeks prior to the onset of illness, health occupation, and inferior hospital ranking as well as longer interval of clinic consulting (longer than 1 day) were the risk factors for SARS-related deaths. Multivariate stepwise logistic regression analysis found four risk factors for SARS-related deaths.Old age (over 60 years) is the major risk factor for SARS-related deaths. Moreover, hospital health workers, the designated hospitals for SARS clinical services and the interval of consulting doctors (less than 1 day) are protective factors for surviving from SARS.

To describe the case fatality rate of SARS in Beijing.Data of SARS cases notified from Beijing Center for Disease Control and Prevention (BCDC) and supplemented by other channels were collected. The data were analyzed by rate calculation.The case fatality rate of SARS in Beijing was 7.66%, and had an ascending trend while the age of cases was getting older, and a descending trend while the epidemic development. The case fatality rate in Beijing was lower than that in other main epidemic countries or regions.The risk of death increases with the increment of age of SARS patients. Beijing is successful in controlling and treating SARS.

To analyze the ageing and related risk factors affecting the death rate of diabetes mellitus in Beijing, and make a correct assessment of risk factors in changing the death rate of diabetes mellitus.The changes of death rate on diabetes mellitus in the past 10 years, from 1991 to 2000 were analyzed and calculated as to making clear what is the effects resulting from the ageing and the risk factors.The death rate of diabetes mellitus was increased to 117.55%, from 1991 to 2000, in which 53.28% were attributing to the ageing and 46.72% to the risk factors.The effects of ageing and risk factors on death rate of diabetes mellitus should be different and the ageing should be a factor more important than the other risk factors.

To assess the impacts of public health interventions on the outbreak of SARS in Beijing by analyzing the intervals between symptom onset, hospital admission and notification of its cases.Data of SARS cases reported from the Beijing Municipal Centers for Disease Prevention and Control (BCDC) were collected and analyzed by descriptive epidemiology.In the early epidemic period, the intervals between the disease onset and the hospital admission seemed irregular, so was the intervals between the hospital admission and the notification. After the middle ten days of April, the intervals turned out to be more regular, and the disordered situation in terms of the hospital admission and the case notification was gradually brought under control.Public health interventions against SARS has revealed positive impacts on SARS control program in Beijing. The timing and sensitivity of epidemic information reporting systems has been greatly improved in Beijing as a result of successful fight against this disease.

To describe the specific features of the contact history of probable cases of severe acute respiratory syndrome (SARS) in Beijing.Data of SARS cases notified from the Beijing Municipal Center for Disease Control and Prevention (BCDC) and supplemented by other channels were collected. All the data were analyzed by descriptive epidemiology.(1) The number of probable cases with contact history was significantly higher than the excluded cases. (2) The proportion of probable cases with contact history descended with epidemic development, but this situation did not occur in health care workers (HCWs). (3) The fatality rate of probable cases with contact history was significantly higher than the cases without contact history (OR = 1.489). (4) The proportion of probable cases with contact history was 85.86% among health care workers, which was significantly higher than that of non-health care workers (85.86% v.s. 56.44%, OR=4.69).(1) The susceptible persons with contact history may not get infected, and the contact history is just a sufficient condition of infecting SARS; (2) There are 3 conceivable reasons for the descending trend of the proportion in probable cases with contact history; (3) The contact history is one of the risk factors of the death of SARS cases; (4) The risk of contacting with SARS among health care workers is approximately 5 times higher than that of non-HCWs.