Molecular Dynamics-Assisted Design of High Temperature-Resistant Polyacrylamide/Poloxamer Interpenetrating Network Hydrogels.

Polyacrylamide has promising applications in a wide variety of fields. However, conventional polyacrylamide is prone to hydrolysis and thermal degradation under high temperature conditions, resulting in a decrease in solution viscosity with increasing temperature, which limits its practical effect. Herein, combining molecular dynamics and practical experiments, we explored a facile and fast mixing strategy to enhance the thermal stability of polyacrylamide by adding common poloxamers to form the interpenetrating network hydrogel. The blending model of three synthetic polyacrylamides (cationic, anionic, and nonionic) and poloxamers was first established, and then the interaction process between them was simulated by all-atom molecular dynamics. In the results, it was found that the hydrogen bonding between the amide groups on all polymers and the oxygen-containing groups (ether and hydroxyl groups) on poloxamers is very strong, which may be the key to improve the high temperature resistance of the hydrogel. Subsequent rheological tests also showed that poloxamers can indeed significantly improve the stability and viscosity of nonionic polyacrylamide containing only amide groups at high temperatures and can maintain a high viscosity of 3550 mPa·S at 80 °C. Transmission electron microscopy further showed that the nonionic polyacrylamide/poloxamer mixture further formed an interpenetrating network structure. In addition, the Fourier transform infrared test also proved the existence of strong hydrogen bonding between the two polymers. This work provides a useful idea for improving the properties of polyacrylamide, especially for the design of high temperature materials for physical blending.

Time lag effects of COVID-19 policies on transportation systems: A comparative study of New York City and Seattle.

The unprecedented challenges caused by the COVID-19 pandemic demand timely action. However, due to the complex nature of policy making, a lag may exist between the time a problem is recognized and the time a policy has its impact on a system. To understand this lag and to expedite decision making, this study proposes a change point detection framework using likelihood ratio, regression structure and a Bayesian change point detection method. The objective is to quantify the time lag effect reflected in transportation systems when authorities take action in response to the COVID-19 pandemic. Using travel patterns as an indicator of policy effectiveness, the length of policy lag and magnitude of policy impacts on the road system, mass transit, and micromobility are investigated through the case studies of New York City (NYC), and Seattle-two U.S. cities significantly affected by COVID-19. The quantitative findings show that the National declaration of emergency had no policy lag while stay-at-home and reopening policies had a lead effect on mobility. The magnitude of impact largely depended on the land use and sociodemographic characteristics of the area, as well as the type of transportation system.

Current risk factors for HIV infection among blood donors in seven Chinese regions.

BACKGROUND: In China, there is a rising concern on the increasing trends of HIV infections in high-risk groups, who make blood donations that might potentially challenge the blood safety. Analyses on current risk factors for HIV infection among Chinese blood donors are urgently needed for developing effective strategies to defer high-risk donors and to warrant the safety of the blood supply. STUDY DESIGN AND METHODS: We recruited 313 HIV-positive and 762 HIV-negative donors from seven study sites in China and evaluated donor demographic characteristics, current medical and behavioral risk factors associated with HIV infection in a case-control survey. Univariable analyses examined the relationship between HIV infection and donor and donation characteristics, medical and behavioral risks, living conditions, and lifestyles. Multivariable logistic regression analyses evaluated the association between selected individual risks and HIV infection. Regression tree analysis was used to select covariates correlated with both HIV infection and individual risks and thus need to be controlled for in logistic regression models. RESULTS: Being a man who has sex with men was associated with the highest odds of HIV infection. Not using a condom, having sex with HIV-infected individuals, having sex partners with sexually transmitted diseases (STDs), having more than two concurrent sex partners, or having an STD were all associated with more than five times higher odds of having HIV. Having remunerated sex was associated with a 2.4 increased odds of having HIV infection. CONCLUSION: High-risk sexual behaviors were among the major risks for HIV infection among Chinese blood donors.

HIV prevalence and incidence estimates among blood donors in five regions in China.

BACKGROUND: Previous data, although scant, indicated that the incidence of HIV in China has increased over the past decade. There is a growing concern about the impact of the HIV epidemic on blood safety. METHODS AND MATERIALS: We used donation data from five geographically-disperse blood centers in 2013-2016 participating in the Recipient Epidemiology and Donor Evaluation Study-III (REDS-III) China program to estimate HIV prevalence and incidence among blood donors. Multivariable logistic regression model was used to examine factors associated with HIV infection in Chinese blood donors. RESULTS: The overall HIV prevalence among first-time donors from 2013 through 2016 was 68.04 per 100,000 donors (95% CI 61.68-74.40). The HIV incidence rate was estimated to be 37.93 per 100,000 person-years (95% CI 30.62-46.97) among first-time donors and 20.55 per 100,000 person-years (95% CI 16.95-24.91) among repeat donors. There was substantial variation in HIV prevalence and incidence rates across blood centers. Multivariable logistic regression results showed that among first-time donors, being male, older than 25 years, minority ethnicity, less than college education, and certain occupations (commercial services, factory workers, retired, unemployed, or self-employed) were associated with positive HIV confirmatory testing results. CONCLUSION: HIV prevalence and incidence among blood donors remain low in the selected five regions in China; however, an increasing trend is observed at some blood centers. It is important to monitor HIV epidemiology in Chinese blood donors on a continuous basis, especially among populations and regions of higher risk.

Estimation of hepatitis B-positive rates in Chinese blood donors by combining predonation and postdonation screening results.

BACKGROUND: Chinese blood centers use Hepatitis B surface antigen (HBsAg) rapid test (RT) in pre-donation and two rounds of screening with different enzyme-linked immunosorbent assays in post-donation. Nucleic acid testing (NAT) on screening non-reactive (SC-) donations has been gradually implemented since 2010. Yet RT+ and SC-/NAT+ donors are seldom included in hepatitis B virus (HBV) positive rate estimates in Chinese blood donors. METHODS: We performed HBsAg neutralization test (NT) on whole blood (WB) with pre-donation RT+ results and post-donation screening reactive (SC+) samples from Mianyang and Chongqing in 2015. The annual totals of pre- and post-donation NT+ donors were combined with the annual totals of SC-/NAT+ donors to derive the estimated HBV positive rates. RESULT: In Mianyang and Chongqing, 59.4% and 68.2% of RT+ donors in Jan-Aug 2015 contributed for NT, 95.5% and 97.2% of which were NT+ respectively. In 2015, 422 and 667 donors from Mianyang and Chongqing respectively were HBsAg RT+, yielding estimated 403 and 648 pre-donation RT+/NT+ deferrals. 411 and 668 post-donation SC+ samples were NT tested from Mianyang and Chongqing, of which 249 and 323 were NT+ respectively. An estimated 63 donors in Mianyang and 88 donors in Chongqing were SC-/NAT+. The estimated HBV confirmed positive rate in blood donors are 1.59% in Mianyang and 1.01% in Chongqing. CONCLUSION: Pre-donation HBsAg RT effectively intercepts donations from HBV infected donors. Using NT confirmatory results from RT+, SC+ and SC-/NAT+ donors, this study provides a model for more accurate estimation for HBV positive rates in China.

Hepatitis C virus prevalence and incidence estimates among Chinese blood donors.

BACKGROUND: Hepatitis C virus (HCV) is an important transfusion-transmitted virus with global significance. The objective of this study was to evaluate the HCV prevalence and incidence among Chinese blood donors from 2013 to 2016. STUDY DESIGN AND METHODS: Whole blood and apheresis platelet donations collected from five Chinese blood centers from June 1, 2013, to December 31, 2016, were screened in parallel by two different enzyme-linked immunosorbent assays for anti-HIV 1/2, hepatitis B surface antigen, anti-HCV, and syphilis. Screening-reactive samples were further confirmed by western blot. Confirmatory positive rates among first-time and repeat donors were used to estimate the prevalence and incidence rates. Multivariable logistic regression modeling was used to examine factors associated with HCV infection. RESULTS: A total of 1,276,544 donations were collected from five Chinese blood centers, of which an estimated 1203 were confirmed HCV positive. The overall HCV prevalence among first-time donors was 166.56 per 100,000 donors (95% confidence interval, 156.04-177.08). The HCV incidence rate was estimated to be 15.21 (95% confidence interval, 11.83-19.56) per 100,000 person-years among repeat donors. Multivariable logistic regression results showed that increased age, lower educational levels, ethnicity, and occupation were all important factors associated with HCV confirmatory status among first-time donors (p < 0.01). CONCLUSIONS: HCV infection is still an important concern for transfusion safety in China. Our findings indicate that continued strong efforts are needed to monitor and control the risk of transfusion-transmitted HCV infection in China. Moreover, to reduce unnecessary donor loss, HCV donor screening procedures should be improved by incorporating confirmatory testing into routine blood center operations.

Blood utilization in five Chinese hospitals shows low hemoglobin thresholds in medical patients.

BACKGROUND: The number of red blood cell units transfused per capita in China is lower than in western countries and the reason(s) for the difference is unknown. STUDY DESIGN AND METHODS: We randomly chose 5050 transfused patients from five Chinese hospitals. We compared transfused cases to nontransfused controls matched for the same underlying diagnosis. We assessed the pretransfusion hemoglobin (Hb) trigger and other clinical characteristics associated with transfusion. After stratifying by underlying disease, we compared pretransfusion Hb level in Chinese hospitals to 12 US hospitals. RESULTS: In 5050 patients who received transfusion, the pretransfusion Hb levels were lower in medical (6.3 g/dL) compared to surgical patients receiving transfusion postoperatively (8.1 g/dL). In patients with nonsurgical diagnoses, the pretransfusion Hb was much lower than that in the United States; the difference in mean Hb level varied by underlying diagnosis from 0.4 to 1.8 g/dL. In case-control analysis of cases (n = 1356) compared to controls (n = 1201), the pretransfusion Hb showed the strongest association with transfusion. Compared to 10 g/dL, the odds ratio (95% confidence interval) for pretransfusion Hb of 7 to 7.9 g/dL was 37.7 (24.8-57.4). CONCLUSION: Transfusion triggers in five Chinese hospitals appear comparable to those in the United States for surgical patients; however, medical patients have lower pretransfusion Hb levels (approx. 6 g/dL). Of the factors assessed, the pretransfusion Hb was most strongly associated with transfusion. The clinical impact of lower transfusion thresholds used in China is unknown.

Extracting Trips from Multi-Sourced Data for Mobility Pattern Analysis: An App-Based Data Example.

Passively-generated data, such as GPS data and cellular data, bring tremendous opportunities for human mobility analysis and transportation applications. Since their primary purposes are often non-transportation related, the passively-generated data need to be processed to extract trips. Most existing trip extraction methods rely on data that are generated via a single positioning technology such as GPS or triangulation through cellular towers (thereby called single-sourced data), and methods to extract trips from data generated via multiple positioning technologies (or, multi-sourced data) are absent. And yet, multi-sourced data are now increasingly common. Generated using multiple technologies (e.g., GPS, cellular network- and WiFi-based), multi-sourced data contain high variances in their temporal and spatial properties. In this study, we propose a "Divide, Conquer and Integrate" (DCI) framework to extract trips from multi-sourced data. We evaluate the proposed framework by applying it to an app-based data, which is multi-sourced and has high variances in both location accuracy and observation interval (i.e. time interval between two consecutive observations). On a manually labeled sample of the app-based data, the framework outperforms the state-of-the-art SVM model that is designed for GPS data. The effectiveness of the framework is also illustrated by consistent mobility patterns obtained from the app-based data and an externally collected household travel survey data for the same region and the same period.

Development and validation of a real-time reverse transcriptase PCR assay for sensitive detection of SFTSV.

BACKGROUND: Severe fever with thrombocytopenia syndrome bunyavirus (sftsv) is an emerging tick-borne rna virus recently identified as the pathogen that causes severe fever with thrombocytopenia syndrome (sfts) in china. the existing commercial nucleic acid testing (comnat) assay with a relatively high claimed limit of quantitative detection (loqd) is not capable of sensitive detection and quantitation of sftsv. Thus, a new real-time reverse transcriptase (rt)-pcr assay with improved sensitivity is needed for clinical diagnosis; it could also be used to screen blood donors if necessary. MATERIALS AND METHODS: We developed a new sftsv rt-pcr nat assay (newnat). About 129 plasma samples from 93 suspected sfts patients with typical clinical symptoms were tested using an anti-sftsv total antibody elisa and both comnat and newnat. The test performance of the two nat assays was evaluated and compared. RESULTS: The newnat had a lower limit for quantitative testing compared to comnat. Twelve samples were comnat negative but newnat positive. Out of 35 suspected sfts patients who were comnat negative and anti-sftsv total antibody negative, four tested positive by the newnat assay and one of these four seroconverted within 2-4 days after testing newnat positive. A high correlation was observed between the cts of the newnat and comnat assays. CONCLUSION: The newnat assay was sensitive for quantitative detection of sftsv and may be applicable to clinical diagnosis and studies of the need for blood donor screening.

The characteristics of hepatitis B surface antigen (HBsAg)-negative hepatitis B virus (HBV) infection in Chinese blood donors: a follow-up study of donors tested negative for HBsAg and reactive for simultaneous nucleic acid testing of HBV, hepatitis C virus, and human immunodeficiency virus.

BACKGROUND: The real infection status of hepatitis B virus (HBV) of hepatitis B surface antigen (HBsAg)-negative yet nucleic acid test (NAT)-positive blood donors is difficult to clarify. Detailed follow-up study is needed for analyzing the infectivity of these blood donors. STUDY DESIGN AND METHODS: Blood donors who screened negative for HBsAg and reactive for simultaneous NAT of HBV, hepatitis C virus (HCV), and human immunodeficiency virus (HIV) were included in a follow-up epidemiologic questionnaire survey and contributed follow-up samples for further testing. The follow-up samples were tested repeatedly for the serologic markers and HBV DNA. The genotypes and sequence mutations of HBV infected by 11 HBV DNA-positive donors were analyzed through the amplification and sequencing of HBV S region. RESULTS: Of the 46 donors included in this study, 89.1% were infected with HBV (41/46), including one (2.2%) window period infection, three (6.5%) recovered infections, and 37 (80.4%) occult HBV infections (OBIs). The S region of HBV was successfully amplified and sequenced for seven donors, five infected with Genotype B (71.4%), one with Genotype C (14.3%), and one with Genotype D (14.3%). Mutations in the S region were detected in four donors (57.1%) CONCLUSIONS: This is the first detailed study with multiple follow-up testing of the HBV infection status among blood donors who were tested negative for HBsAg and reactive for simultaneous NAT of HBV, HCV, and HIV. Most of these donors were infected with HBV with very low viral load. Our findings indicate that it is important to improve the sensitivity of NAT so as to decrease the residual risk of transfusion-transmitted HBV infection.

The association of elevated alanine aminotransferase levels with hepatitis E virus infections among blood donors in China.

BACKGROUND: Transfusion transmission of hepatitis E virus (HEV) is an emerging health risk, yet blood donors are rarely screened for this pathogen. Many blood centers instituted screening of blood donors for elevated levels of alanine aminotransferase (ALT) levels to prevent hepatitis C virus, which has continued in China. We evaluated whether elevated ALT levels were associated with HEV among blood donors in China. STUDY DESIGN AND METHODS: Blood samples were collected from 9069 qualified volunteer blood donors from four blood centers in China. A total of 5023 had elevated ALT levels, that is, more than 40 IU/L, and 4046 samples had normal ALT. We tested all the 9069 samples for anti-HEV immunoglobulin (Ig)M, anti-HEV IgG, and HEV antigen. Those who were positive for anti-HEV IgM or HEV antigen were tested individually for HEV RNA by polymerase chain reaction. RESULTS: The prevalence of anti-HEV IgG in donors with elevated ALT levels (33.3%) was higher than those with normal ALT (24.9%; p < 0.01). The prevalence of anti-HEV IgM was similar in donations with increased ALT (1.41%) and normal ALT (1.46%). More ALT-elevated donations were HEV antigen positive, 62 of 5023 (1.23%), than were ALT-normal donations, seven of 4046 (0.17%; p < 0.01). Six donors with elevated ALT levels and acute HEV infection markers (anti-HEV IgM or HEV antigen) were HEV RNA positive. CONCLUSION: Markers of active infection including HEV antigen and HEV RNA are significantly more common among donors with elevated ALT levels in China. These data support the fact that ALT testing of donors to HEV antigen or HEV RNA would have greater specificity and exclude fewer acceptable donors.

Migration patterns of hepatitis C virus in China characterized for five major subtypes based on samples from 411 volunteer blood donors from 17 provinces and municipalities.

UNLABELLED: We investigated the migration patterns of hepatitis C virus (HCV) in China. Partial E1 and/or NS5B sequences from 411 volunteer blood donors sampled in 17 provinces and municipalities located in five large regions, the north-northeast, northwest, southwest, central south, and southeast, were characterized. The sequences were classified into eight subtypes (1a, n = 3; 1b, n = 183; 2a, n = 83; 3a, n = 30; 3b, n = 44; 6a, n = 55; 6n, n = 10; 6v, n = 1) and a new subtype candidate. Bayesian evolutionary analysis by sampling trees of the E1 sequences of the five major subtypes revealed distinct migration patterns. Subtype 1b showed four groups: one is prevalent nationwide with possible origins in the north-northeast; two are locally epidemic in the central south and northwest, respectively, and have spread sporadically to other regions; and the fourth one is likely linked to the long-distance dispersion among intravenous drug users from the northwest. Subtype 2a showed two groups: the larger one was mainly restricted to the northwest and seemed to show a trend toward migration via the Silk Road; the smaller one was geographically mixed and may represent descendants of those that spread widely during the contaminated plasma campaign in the 1990s. Subtype 3a exhibited three well-separated geographic groups that may be epidemically unrelated: one showed origins in the northwest, one showed origins in the southwest, and the other showed origins in the central south. In contrast, subtype 3b had a mixture of geographic origins, suggesting migrations from the southwest to the northwest and sporadically to other regions. Structurally resembling the tree for subtype 3a, the tree for subtype 6a showed four groups that may indicate migrations from the central south to southeast, southwest, and northwest. Strikingly, no subtype 6a strain was identified in the north-northeast. IMPORTANCE: With a population of greater than 1.3 billion and a territory of >9.6 million square kilometers, China has a total of 34 provinces and municipalities. In such a vast country, the epidemic history and migration trends of HCV are thought to be unique and complex but variable among regions and are unlikely to be represented by those observed in only one or at best a few provinces and municipalities. However, due to the difficulties in recruiting patients, all previous studies for this purpose have been based only on data from limited regions, and therefore, geographical biases were unavoidable. In this study, such biases were greatly reduced because we utilized samples collected from volunteer blood donors in 17 provinces and municipalities. To our knowledge, this is the first study in which the HCV isolates represented such a large portion of the country, and thus, the results should shed light on the current understanding of HCV molecular epidemiology.

A study of seroprevalence and rates of asymptomatic viremia of severe fever with thrombocytopenia syndrome virus among Chinese blood donors.

BACKGROUND: Severe fever with thrombocytopenia syndrome virus (SFTSV), an emerging tick-borne pathogen that can cause fatal severe fever with thrombocytopenia syndrome, was first identified in China in 2009. Limited evidence suggests that SFTSV can be transmitted between humans via blood contact, raising concerns over transfusion safety. A study of donor samples from three Chinese blood centers was conducted to investigate the seroprevalence and rate of SFTSV viremia among Chinese blood donors. STUDY DESIGN AND METHODS: From April 16 to October 31, 2012, a total of 17,208 plasma samples were collected from donors at Xinyang (located in an SFTSV-endemic area), Mianyang, and Luoyang Blood Centers. Assessment of anti-SFTSV total antibody was performed on all samples using enzyme-linked immunosorbent assay. Repeat-reactive samples were tested for SFTSV RNA using reverse transcription (RT)-real-time polymerase chain reaction (PCR) assay with Taqman probes. In addition, 9960 of the Xinyang samples were tested in pools of 4 by the same PCR method and each of the samples in a reactive pool was tested individually. RESULTS: Donor seroreactivity rates were as follows: Xinyang, 0.54% (80/14,752); Mianyang, 0.27% (3/1130); and Luoyang, 0.28% (3/1326). All seroreactive samples were negative on RT-PCR single-sample testing. Two RT-PCR-reactive donor samples were identified, both with estimated viral load of less than 20 plaque-forming units/mL. The RNA prevalence rate for SFTSV among donors in Xinyang was 0.02%. CONCLUSION: This was the first multiregion study of SFTSV sero- and viral prevalence among Chinese blood donors. Viral prevalence was low and no seroreactive sample was viremic, suggesting a limited impact of SFTSV on blood safety in China.

Risk factors for hepatitis B and C infection among blood donors in five Chinese blood centers.

BACKGROUND: Few studies were conducted on hepatitis B and C virus (HBV and HCV, respectively) risk factors among Chinese blood donors in recent years since voluntary donors replaced commercial donors. STUDY DESIGN AND METHODS: A case-control survey was conducted in HBV- or HCV-positive and -negative donors from five blood centers in China between September 2009 and April 2011. Case status was defined by having a reactive result on Monolisa HBsAg Ultra (Bio-Rad) for HBV and Ortho anti-HCV EIA 3.0 (Johnson & Johnson) for HCV. Controls were randomly selected qualified blood donors matched to cases by donation month and blood center. Specific test-seeking, medical-related, and behavioral risk factors were compared by HBV and HCV status using chi-square tests or Fisher's exact tests with Bonferroni correction. RESULTS: A total of 364 HBV cases, 174 HCV cases, and 689 controls completed the survey; response rates were 66.2, 47.3, and 82%, respectively. HCV-positive donors were significantly more likely to report having a blood transfusion history (23.4% vs. 3.0%, p < 0.0001) and ever living with a person with illegal drug injection (6.0% vs. 0.5%, p < 0.0001) than controls. Having intravenous and intramuscular injections in the past 12 months and ever having a tattoo are marginal risk factors for HCV (p values < 0.01). No specific risk factor for HBV was identified. CONCLUSION: History of previous transfusion and living with illegal drug users are risk factors for HCV infection among Chinese blood donors from five regions. Test-seeking behavior is not associated with HBV or HCV infections.

Blood transfusion practice: a survey in Sichuan, China.

OBJECTIVE: To get full knowledge of current conditions and development in the past seven years of clinical transfusion practice in Sichuan, China. STUDY DESIGN AND METHODS: This survey was performed by means of a questionnaire which consisted of three parts of questions including basic conditions of blood banks in the hospitals, procedures for clinical blood transfusion and the utilization of different types of blood products. Thirty-five representative hospitals from different geographic locations in Sichuan province participated in this survey. RESULTS: All of the 35 hospitals returned the questionnaires and 33 hospitals (94.3%) answered the questions completely. The blood bank information system began to be used by more hospitals from 2006 (21.21%, 7/33) to 2012 (48.48%, 16/33). Automated grouping and cross-matching systems have not been used in level 2 hospitals and only 3 level 3 hospitals used automated systems in 2012. Still less common were procedures for evaluation of blood order forms for appropriateness (2/33, 6.06%) and evaluation of appropriateness and effect of blood component transfusion (8/33, 24.2%), and all the hospitals having these procedures are level 3 hospitals. The percentage of whole blood usage in the volume of all types of blood products used decreased a lot from 7.45% in 2006 to 0.16% in 2010. Technological instruments for bedside checking are not used by any of the hospitals. CONCLUSIONS: The transfusion service degree of the hospitals in Sichuan, China, has developed a lot in the past seven years; however, there are still some problems including whole blood still being used, albeit decreasing; lack of independent blood banks within the hospitals; lack of dedicated personnel for the transfusion services; lack of education; lack of blood bank information systems and automation; lack of screening for appropriateness for blood orders. Thus, the quality control center of clinical blood transfusion (QCCCBT) of Sichuan province should help the transfusion departments to attract more investment in staffing, equipment and information system from the hospitals, enhance the training of transfusion department staffs, and emphasize the supervision of transfusion department's work on directing clinical blood utilization and evaluating clinical transfusion appropriateness.

Hepatitis B virus infection in a cohort of HIV infected blood donors and AIDS patients in Sichuan, China.

BACKGROUND: Co-infections of HBV and HIV are frequent due to similar routes of transmission. In that transmission through blood is an important route for both HBV and HIV, evaluation of the prevalence of HBV in HIV infected blood donors may be important for transfusion safety. In addition, because the epidemiological characteristics of HBV in HIV infected patients and blood donors may differ from each other, understanding of it could be significant for therapy and prevention of HBV in HIV infected adults. However, data reported on these in Chinese people remains limited. METHODS: 614 HIV confirmed positive samples were collected from blood donors and patients and were screened for HBsAg and HBV DNA. The samples screened reactive for HBsAg or positive for HBV DNA were tested for the other serological markers of HBV including anti-HBs, HBeAg, anti-HBe and anti-HBc. For the samples tested positive for HBV DNA, the S region of HBV was amplified by nested PCR and the HBV genotypes were determined. RESULTS: HBV coinfections were found in 12.9% (79/614) HIV infected individuals including 42/417(10.1%) blood donors and 37/197 (18.8%) AIDS patients. In the HBsAg positive individuals, 80.0% were HBeAg negative in which 10.0% were HBV DNA negative and 38.3% with HBV DNA lower than 2000 IU/ml. The average HBV DNA levels were lower in donors than in patients. In the HBV DNA positive populations, HBV genotypes B, A and C accounted for 48.1%, 22.8% and 8.86% respectively. Mutations related to the failure of HBsAg detection were found in 2 of the 4 HBsAg-/HBV DNA + subjects. CONCLUSIONS: High prevalence of HBV in HIV infected individuals was found in this study. Hence, we recommend routine testing of HBV for patients newly diagnosed with HIV/AIDS in China. Some HIV-HBV co-infected patients remain undiagnosed if only conventional serological markers for HBV are used and it's important to detect HBV DNA for HIV infected patients. HBV DNA levels were relatively low in HBeAg negative patients, thus this serologic marker may be useful in prioritizing patients on their need for HBV treatment in settings in which HBV DNA is not available.

Blood safety and availability: continuing challenges in China's blood banking system.

Social and economic development, along with increased health care coverage, has caused a sharp increase in the clinical demand for blood in China. Whole blood collection has increased rapidly in the past decade but has failed to keep pace with the ever-increasing demand. Overall, the country's blood safety has been improved with 99% of whole blood donations collected from voluntary unpaid donors. However, the unmet clinical demand for blood and the increasing incidence of human immunodeficiency virus and syphilis in the general population pose new challenges to China's blood banking system. To ensure a safe and adequate blood supply, continued efforts are required to recruit and retain a sufficient number of low-risk voluntary blood donors, improve donor prescreening and blood testing process, ease donor restrictions, and strengthen patient blood management.

Hepatitis E virus seroprevalence and molecular study among blood donors in China.

BACKGROUND: The risk of hepatitis E virus (HEV) infection from blood transfusion has aroused increasing concern in many countries. The aim of this study was to analyze the potential risk of HEV infection through blood transfusion in China. STUDY DESIGN AND METHODS: Qualified blood donations and donations with isolated alanine aminotransferase (ALT) elevations from five geographically diverse Chinese regions were tested for anti-HEV immunoglobulin (Ig)M and IgG and HEV antigen. The positive samples for anti-HEV IgM and HEV antigen were tested for HEV RNA. HEV open reading frame (ORF)2 partial sequences were analyzed from HEV RNA-positive samples. RESULTS: The seroprevalence rates of HEV antigen and anti-HEV IgM and IgG among qualified donations were 0.06% (6/10,741), 1.02% (109/10,741), and 27.42% (2945/10,741), respectively. Samples with isolated ALT elevations had higher prevalence of HEV markers, namely, HEV antigen of 0.25% (2/797), anti-HEV IgM of 2.76% (22/797), and anti-HEV IgG of 40.02% (319/797). The HEV antibody prevalence varied significantly by age, sex, and geographic region. All 131 samples that were anti-HEV IgM positive were negative for HEV RNA, whereas four of eight (50%) samples positive for HEV antigen were HEV RNA positive. HEV ORF2 sequences from three of four HEV RNA-positive samples were determined and grouped with Genotype 4. CONCLUSION: Qualified donations after routine blood donor screening still carry potential risk for transmitting HEV. HEV antigen screening could be one measure to reduce the risk of HEV transmission by blood transfusion.

Blood donor management in china.

Despite a steady increase in total blood collections and voluntary non-remunerated blood donors, China continues to have many challenges with its blood donation system. The country's donation rate remains low at 9%o, with over 60% of donors being first-time donors. Generally there is a lack of adequate public awareness about blood donation. The conservative donor selection criteria, the relatively long donation interval, and the small donation volume have further limited blood supply. To ensure a sufficient and safe blood supply that meets the increasing clinical need for blood products, there is an urgent need to strengthen the country's blood donor management. This comprehensive effort should include educating and motivating more individuals especially from the rural areas to be involved in blood donation, developing rational and evidence-based selection criteria for donor eligibility, designing a donor follow-up mechanism to encourage more future donations, assessing the current donor testing strategy, improving donor service and care, building regional and national shared donor deferral database, and enhancing the transparency of the blood donation system to gain more trust from the general public. The purpose of the review is to provide an overview of the key process of and challenges with the blood donor management system in China.

Interleukin-28B genetic variations and spontaneous clearance of hepatitis C antibody-positive blood donors in China.

BACKGROUND: Single-nucleotide polymorphisms (SNPs) near the interleukin (IL)28B gene have been shown to be associated with spontaneous clearance of hepatitis C virus (HCV) infection in western populations. Anti-HCV-reactive and HCV RNA-negative samples were often found in Chinese blood donors. This study was to determine whether the IL28B gene variant is also associated with the natural outcome of HCV infection in Chinese blood donors. STUDY DESIGN AND METHODS: A total of 111 anti-HCV-negative blood donors and 100 anti-HCV-reactive subjects were enrolled in this study. HCV-infected blood donors were classified into spontaneous clearance group and chronic infection group through HCV RNA detection. IL28B genetic variations (rs8099917 and rs12979860) were genotyped by polymerase chain reaction and direct sequencing. RESULTS: A total of 24 (24.0%) donors spontaneously cleared HCV. The rs12979860 C allele frequency was 90.3% and the rs8099917 T allele frequency was 96.7% in our study. The rs12979860 CC genotype was strongly associated with spontaneous HCV clearance. Female blood donors had a higher rate of spontaneous HCV clearance than male donors (15/42 [35.7%] vs. 9/58 [15.5%], p = 0.02). CONCLUSIONS: The rs12979860 CC variant upstream of IL28B gene is associated with spontaneous clearance of HCV in Chinese blood donors and female donors are more likely to clear HCV infection than male donors.