Survival of Salmonella Typhimurium, Listeria monocytogenes, and ESBL Carrying Escherichia coli in Stored Anaerobic Biogas Digestates in Relation to Different Biogas Input Materials and Storage Temperatures

Anaerobic digestates derived from agricultural mesophilic biogas plants are mainly used as organic fertilizers. However, animal derived pathogens could persist in the anaerobic digestates (ADs) posing an epidemiological risk. The present study investigated whether storage of ADs could reduce Salmonella Typhimurium, Listeria monocytogenes, and ESBL carrying Escherichia coli and whether reduction rates are dependent on temperature and substrate. Quantified bacterial suspensions were used to inoculate ADs derived from five biogas plants using different input materials to investigate the substrate dependence of the pathogen reduction. ADs were stored over six months with four different temperature profiles each representing six consecutive months, and, thus, the four seasons. Pathogen reduction during storage was shown to be strongly dependent on the temperature but also on the type of AD. This influence was higher at low temperatures. At higher temperatures (spring and summer profiles), a 5-log reduction was achieved after twelve weeks for S. Typhimurium, after twenty weeks for E. coli (ESBL) and after twenty-four weeks for L. monocytogenes in all ADs, respectively. In contrast at lower temperatures (autumn and winter profiles), a 5-log reduction was reached after twenty-four weeks for S. Typhimurium and not reached for ESBL-E. coli and L. monocytogenes. In conclusion, storing the ADs after the biogas process improves the hygienic quality and reduce the risk of introducing pathogens to the environment, but each case should be evaluated individually considering the composition of the ADs and the storage temperatures.

Transfusion Transmissible Infections in Blood Donors in the Province of Bié, Angola, during a 15-Year Follow-Up, Imply the Need for Pathogen Reduction Technologies

Transfusion transmissible infections (TTIs), caused by hepatitis B virus (HBV), human immunode-ficiency virus (HIV), hepatitis C virus (HCV), and syphilis, have a high global impact, especially in sub-Saharan Africa. We evaluated the trend of these infections over time in blood donors in Angola. A retrospective cross-sectional study was conducted among blood donors in Angola from 2005 to 2020. Additionally, frozen samples obtained from blood donors in 2007 were investigated to identify chronic HCV carriers and possible occult HBV infection (OBI). The overall prevalence of HBV, HCV, HIV, and syphilis was 8.5, 3, 2.1, and 4.4%, respectively, among 57,979 blood donors. HBV was predominant among male donors, while the remaining TTIs were predominant among women. Donors >50 years had a significantly high prevalence for all TTIs. Chronic HCV infection was ab-sent in 500 samples tested and OBI was present in 3%. Our results show the continued high prev-alence of TTIs among blood donors in Angola. Most infections showed a significantly low preva-lence in years with campaigns seeking voluntary blood donors, thus, reinforcing the importance of this type of donor to ensure safe blood. Africa, with a high prevalence of diverse pathogens, should consider cost-effective pathogen reduction technologies, once they are commercially accessible, to increase the availability of safe blood.

The 4-Year Experience with Implementation and Routine Use of Pathogen Reduction in a Brazilian Hospital

(1) Background: We reviewed the logistics of the implementation of pathogen reduction (PR) using the INTERCEPT Blood System™ for platelets and the experience with routine use and clinical outcomes in the patient population at the Sírio-Libanês Hospital of São Paulo, Brazil. (2) Methods: Platelet concentrate (PC), including pathogen reduced (PR-PC) production, inventory management, discard rates, blood utilization, and clinical outcomes were analyzed over the 40 months before and after PR implementation. Age distribution and wastage rates were compared over the 10 months before and after approval for PR-PC to be stored for up to seven days. (3) Results: A 100% PR-PC inventory was achieved by increasing double apheresis collections and production of double doses using pools of two single apheresis units. Discard rates decreased from 6% to 3% after PR implementation and further decreased to 1.2% after seven-day storage extension for PR-PCs. The blood utilization remained stable, with no increase in component utilization. A significant decrease in adverse transfusion events was observed after the PR implementation. (4) Conclusion: Our experience demonstrates the feasibility for Brazilian blood centers to achieve a 100% PR-PC inventory. All patients at our hospital received PR-PC and showed no increase in blood component utilization and decreased rates of adverse transfusion reactions.

Pathogen Reduced Cryoprecipitate and Fibrinogen Concentrate Have Delayed Resuscitation of Simulated Dilutional Coagulopathy in a Microfluidic Model of Bleeding When Compared to Cryoprecipitate

Impaired fibrinogen function, one component of trauma-associated coagulopathy, is highly associated with increased mortality in patients with severe traumatic bleeding. Fibrinogen replacement is crucial for improving outcomes in bleeding patients. The two most common clinically-used hemostatic adjuncts for fibrinogen supplementation are fibrinogen concentrates (FibCon) and cryoprecipitate (Cryo), yet which of these products provides better hemostatic resuscitation remains controversial. Where FibCon is predominantly a source of fibrinogen, Cryo contains additional factors which may enhance hemostatic efficacy, such as FVIII and FXIII (inherent to clot strength and fibrin crosslinking) and von Willebrand factor (VWF, important for platelet adhesion and aggregation). Cryo poses more logistical challenges than FibCon, as Cryo is a frozen product that requires thawing (20 minutes) prior to use, and has a shelf life of 4-6 hours post thaw. FibCon is lyophilized, and can be reconstituted and used within 10 minutes, but with a cost roughly 3 times that of Cryo, use of FibCon can be cost-prohibitive. Ultimately, in the setting of hemostatic resuscitation, every minute matters and each minute delay in blood product transfusion is associated with a 5% increase in mortality. Moreover, Cryo is associated with an increased risk of transfusion transmitted infection (TTI).Thus, there is a need for an immediately available and safe fibrinogen source for use in hemostatic resuscitation. Pathogen reduction (PR) of blood products renders any nucleic acid-containing source replication incompetent via crosslinking using psoralens and ultraviolet light. PR was recently adapted for use with cryoprecipitate, yielding a novel hemostatic adjunct - pathogen reduced cryoprecipitated fibrinogen complex, or PR-Cryo FC. We have previously shown PR-Cryo FC stored out to 10 days performs similarly to Cryo and FibCon in current standard assays used to assess hemostatic function. However, as primary hemostasis is dictated by physiologically relevant flow conditions, we wanted to determine if PR of cryoprecipitate altered its hemostatic function during resuscitation of dilutional coagulopathy using a microfluidic model of hemorrhage. Healthy human whole blood (WB), Cryo, FibCon, and PR-Cryo FC were stained with fluorescent antibodies specific for VWF, CD41, fibrinogen, and FXIII. Stained WB was diluted 3:7 in 0.9% NaCl to induce dilutional coagulopathy (dWB). dWB was resuscitated 1:5 with stained adjuncts (Cryo:dWB, FibCon:dWB, or PR-Cryo FC:dWB) and perfused at three different shear rates (150, 500, 3500 1/s) through a microfluidic model of hemorrhage (a lumen that "bleeds" through an injury site into a collagen/tissue factor-coated extravascular space). Occlusion of the injury site was defined as the point at which clot formation sealed the injury site for > 3 minutes. The time from initial perfusion to occlusion was defined as the bleeding time (BT, seconds). If no seal was formed, the assay was stopped at 20 minutes, and the assay given a BT of 1200 seconds. Real-time phase and fluorescent images of the injury site were acquired. Data was extracted from real-time phase and fluorescent images using MATLAB. Both FibCon:dWB and PR-Cryo FC:dWB had significantly increased BT compared to Cryo:dWB at low shear (150 1/s). PR-Cryo FC:dWB had significantly increased BT compared to Cryo:dWB at medium shear (500 1/s), and at high shear (3500 1/s) there were no significant differences in BT between hemostatic adjuncts. However, kinetic analysis at high shear revealed there was a significant delay in clot formation and accumulation in the injury site, such that by 5 minutes, Cryo:dWB had filled 75% of the injury site and FibCon:dWB and PR-Cryo FC:dWB had only filled 50% of the injury site. Real-time fluorescent image analysis showed that both FibCon:dWB and PR-Cryo FC:dWB had reduced VWF deposition at the injury site compared to Cryo:dWB, and this led to a delays in platelet recruitment. FibCon has less VWF than Cryo, which would explain the delayed VWF deposition and platelet recruitment. In contrast, PR-Cryo FC and Cryo have similar amounts of VWF, suggesting that VWF from PR-Cryo FC has limited binding to the collagen-coated injury site, and as PR-Cryo FC:dWB phenocopies FibCon:dWB during clot formation at high shear, this suggests that pathogen reduction of Cryo may impair early VWF mediated capture of platelets at high shear. Disclosures Spinella: Secure Transfusion Services: Current Employment, Current holder of individual stocks in a privately-held company, Current holder of stock options in a privately-held company; Cerus Corporation: Consultancy, Research Funding.

Sewage Treatment through Constructed Wetland System Tailed by Nanocomposite Clay Filter: A Clean Green Initiative

Sewage treatment through constructed wetland is an ecofriendly and sustainable approach proven effective worldwide. Constructed wetland with appropriate species is capable of eliminating all pollutants in sewage, except pathogen removal. An additional polishing treatment is required to eliminate pathogen. Optimization of HLR in CWS was executed by applying first order kinetics. Nanocomposite clay filter with economically viable materials was synthesized and disinfection ability was evaluated. A novel approach integrating constructed wetland system tailed by nanocomposite clay filter was designed. Control was setup with constructed wetland system devoid of plants integrated with clay filter devoid of nanoparticles. The constructed wetland system devoid of plants was used as plants play a vital role in the removal of pollutants. The quality of the influent for (n=20) BOD, COD, TKN, TP, TSS, TDS, SO4, Cl, lead and iron were 248, 345, 26, 4.8, 350, 450, 50, 48, 0.2, 5 mg/L respectively. The quality of effluent in the control was 145, 225, 18, 3.8, 185, 345, 31, 30, 0.6, 2 mg/L for BOD,COD, TKN, TP, TSS, TDS, SO4, Cl, lead and iron respectively. While in the test, 10, 30, 2, 1, 30, 128, 13, 12, BDL, BDL mg/L for BOD, COD, TKN, TP,TSS, TDS, SO4, Cl, lead and iron respectively. The inlet concentration of T.C, F.C and E.coli were 42.1x106-6.3x108, 4.9x105-14.4x106 and 7.8x103-3.8x105 respectively. The pathogen reduction in log removal for test and control units were 5.4 and 1.1 for T.C, 4.4 and 1.2 for F.C and 3 and 1 for E.coli. Thus it is a clean green initiative combating the limitations of disinfection surpassing the existing barriers.