To provide a safe environment, behavioral health settings must adhere to "ligature-resistant" protocols for patients at risk of harm to themselves or others. However, certain bathroom ligature-resistant fixtures alter environmental controls, such as sinks and showerheads, and increase the risk of water-borne pathogens due to low water output settings, highlighting the importance of an interdisciplinary water management program. We describe how ligature-resistant water fixtures may have been associated with a possible case of hospital-associated Legionellosis.

Objective: To determine if the high-level personal protective equipment used in the treatment of high-consequence infectious diseases is effective at stopping the spread of pathogens to healthcare personnel (HCP) while doffing.Background: Personal protective equipment (PPE) is fundamental to the safety of HCPs. HCPs treating patients with high-consequence infectious diseases use several layers of PPE, forming complex protective ensembles. With high-containment PPE, step-by-step procedures are often used for donning and doffing to minimize contamination risk to the HCP, but these procedures are rarely empirically validated and instead rely on following infection prevention best practices.Methods: A doffing protocol video for a high-containment PPE ensemble was evaluated to determine potential contamination pathways. These potential pathways were tested using fluorescence and genetically marked bacteriophages.Results: The experiments revealed existing protocols permit contamination pathways allowing for transmission of bacteriophages to HCPs. Updates to the doffing protocols were generated based on the discovered contamination pathways. This updated doffing protocol eliminated the movement of viable bacteriophages from the outside of the PPE to the skin of the HCP.Conclusions: Our results illustrate the need for quantitative, scientific investigations of infection prevention practices, such as doffing PPE.

Background: Aeromonas hydrophila is a gram-negative bacterium that is found in water and can cause infections in hospitalized patients. Since May 2020, 13 Aeromonas Bloodstream Infections (BSI) were identified by infection prevention in patients undergoing Continuous Renal Replacement Therapy (CRRT) in a surgical Intensive Care Unit (ICU). A multidisciplinary team was formed to develop strategies and solutions for appropriate dialysis wall box use and maintenance.

Abstract Background Personal protective equipment (PPE) is the cornerstone of healthcare worker (HCW) safety and prevention of the spread of pathogens. To limit the potential risk to HCWs, healthcare institutions have employed infection control policies and procedures. When treating patients with high consequence infectious diseases, such as Ebola virus disease, HCWs wear complex personal protective equipment (PPE) ensembles that cover their entire body with multiple layers. These layers build redundancy to ensure protection of the HCWs' skin and clothing. Manufacturers typically provide recommendations for donning and doffing individual PPE pieces, but protocols differ between healthcare institutions for PPE ensembles. These PPE ensembles and their associated doffing protocols are rarely tested empirically. Methods We reviewed footage of the doffing protocol currently employed at a Regional Emerging Special Pathogen Treatment Center. From this analysis we identified potential contamination pathways which we verified by using a fluorescent pathogen proxy. To account for viable pathogen susceptibility to alcohol-based disinfectant, HCWs donned the PPE ensemble and were then contaminated with three genetically marked bacteriophages (phage). After completing the doffing protocol, the HCW’s skin and PPE were swabbed to test for the transfer of viable phage to the HCW. Results All four of the HCWs that completed the initial doffing protocol had a high recovery of phage from at least one sampling location. Subsequently, we implemented interventions to both the equipment and the doffing procedure. In nine trials with this modified protocol, no viable phage was recovered from any of the HCWs. Recovery of Bacteriophage Transferred to HCW during Doffing Before and After Protocol Interventions. N=4 subjects for original protocol, N=9 subjects for revised protocol. Percentage of HCW for whom bacteriophage PCR was positive, average density of recovered phage when available--% (avg density). X- PCR positive, phage inactivated Conclusion Our experiments revealed potential contamination pathways that allowed for high densities of viable phage to move from areas of the outermost layers of PPE to the skin and clothing of HCWs. While the individual PPE functioned correctly, the original ensemble and doffing procedure were not effective. Our updated protocol eliminated phage contamination. This study highlights the need for infection prevention protocols to be evaluated in an empirical manner in a framework such as this. Disclosures All Authors: No reported disclosures

Intrahost SARS-CoV-2 EvolutionIn this report, the evolution of SARS-CoV-2 in response to immunologic and monoclonal-antibody pressure is explored in five patients with B-cell deficiency.

Abstract Background Central line associated bloodstream infections (CLABSI) are a recognized complication of all central venous access devices including pulmonary artery catheters (PAC). At our institution, PACs are utilized frequently, often for prolonged durations, for patients with advanced heart failure in the cardiac care unit (CCU) who are awaiting heart transplant. In early summer 2018, our hospital infection prevention (IP) department detected an uptick in CLABSI attributable to the CCU. After 9 months of zero CLABSI, two CLABSIs attributable to the CCU were identified during a 3 month period from November 2017-January 2018. Four additional CLABSIs were identified between May-July 2018 prompting an investigation by IP. Review of the 9 CLABSIs attributed to the CCU from May 2018 – June 2019 led IP to prioritize improving PAC insertion practices in our cardiac catheterization lab as a mean to reducing CLABSI (see table 1). Methods IP performed 5 observations of PAC insertion in the cath lab. During the observations of skin preparation, the prep time was performed correctly 40% of the time, correct application 60% of the time and dry time 60% of the time (see table 2, Figure1). Interventions included scheduling a training day for all cath lab staff with the skin prep vendor, performing competency check-offs, and identifying super-users to train future staff. Furthermore, skin antiseptic utilization according the manufacturer's instructions for use was implemented, the coverage area for the applicator was reviewed and a chart for reference was provided.The staff was provided with posters on correct skin prep technique as a visual cue in the procedure room. Results Since the project was implemented in September 2019, there has been 1 CLABSI identified that was possibly related to a PAC inserted in the cath lab. During this time 3 CLABSIs were identified in the CCU but were felt to be unrelated to cath lab insertion. Conclusion Since the project was implemented in September 2019, there has been 1 CLABSI identified that was possibly related to a PAC inserted in the cath lab. During this time 3 CLABSIs were identified in the CCU but were felt to be unrelated to cath lab insertion. Disclosures All Authors: No reported disclosures

Abstract Background Most individuals diagnosed with mild to moderate COVID-19 are no longer infectious after day 10 of symptom onset and those with severe or critical illness from COVID are typically not infection after day 20 day of symptom onset. Recovered persons can continue to test positive for SARS-CoV-2 by PCR via detection of non-viable RNA in nasopharyngeal specimens for up to three months (or longer) after illness onset. It is also know known that severely immunocompromised patients may produce replication-competent virus greater than 20 days from symptom onset and may require, per CDC recommendations, “additional testing and consultation with infectious diseases specialists and infection control experts”. We aim to discuss four case studies of severely immunocompromised patients who exhibited signs of persistent COVID-19 infection of COVID and how we managed transmission-based precautions in our hospital through sequencing and evaluation of cycle thresholds (CT) values and subgenomic RNA detection. Methods Residual nasopharyngeal (NP) samples were collected on patients exhibiting persistent COVID like symptoms. These samples underwent N gene and N gene subgenomic RNA (sgRNA) real-time reverse transcription polymerase chain reaction (rRT-PCR) testing. Results Analysis of longitudinal SARS-CoV-2 sequence data demonstrated within-patient virus evolution, including mutations in the receptor binding domain and deletions in the N-terminal domain of the spike protein, which have been implicated in antibody escape. See Figures 1 and 2. Figure 1. Timelines of Identified Patients 1 and 2 Patient 1: 46-year-old woman with recently diagnosed stage IV diffuse large B-cell lymphoma for which she was treated with 2 cycles of R-CHOP. Patient 2: 38-year-old woman with history of myelodysplastic syndrome, peripheral blood stem cell transplant with chronic graft versus host disease of the GI tract, skin, and eyes as well as CMV enteritis, and she was maintained on rituximab, mycophenolate mofetil, prednisone, and monthly IVIG without recent changes to her immunosuppression. Figure 2. Timeline of Identified Patients 3 and 4 Patient 3: 44 year-old man with prior history of thymoma s/p thymectomy Patient 4: 46 year-old man who was initially diagnosed with marginal zone lymphoma approximately 2.5 years ago. He was initially treated with bendamustine and rituximab and achieved remission. He was then continued on maintenance rituximab without significant complications for a planned two years. Conclusion Differentiating between prolonged viral shedding of non-infectious RNA and persistent replicating viable virus can be difficult to determine without full evaluation of a patient’s clinical picture and timeline. Consultation between laboratory, infectious diseases, and infection prevention experts to provide appropriate level of guidance for precautions and treatment may be warranted. Testing by PCR and analysis of CT values may provide key findings of viral replication in immunocompromised hosts, indicating the need for evaluation of additional treatment and maintaining isolation status in healthcare settings. Disclosures All Authors: No reported disclosures

Abstract Background The COVID-19 pandemic required hospitals to care for influxes of patients in cohort locations during critical shortages of personal protective equipment (PPE). Safety zones can be used to protect healthcare workers caring for patients with infectious pathogens. During the COVID-19 pandemic, our hospital developed a Warm Zone model (WZM) to streamline the care of patients with COVID. We established specific areas in our COVID cohort units where staff were permitted to bridge between rooms without doffing gowns, but still doffing gloves and performing hand hygiene between patients. We recognized that a WZM could inadvertently increase risk of nosocomial transmission of pathogens if gowns acted as fomites. For this reason, patients with known infectious pathogens were excluded from the WZM. To measure for unintended harmful consequences of the WZM, our Infection Prevention (IP) department performed surveillance for hospital onset (HO) Clostridioides difficile (CDI), Carbapenem-resistant enterobacteriaceae (CRE) and Methicillin-resistant Staphyloccocus aureus (MRSA) bloodstream infections on units that implemented the WZM. Methods Two intensive care units and 3 wards where COVID positive patients were cohorted were included in surveillance. The timeframe for this analysis was 7/1/2020 - 3/31/2021. An electronic surveillance system was used to measure HO infections. The National Healthcare Surveillance Network (NHSN) LabID definitions were used when determining HO CDI and MRSA bloodstream infections (BSI). Results During the study period, there were no HO CRE, 1 HO CDI, and 2 HO MRSA BSI in cohort units. There was no evidence to suggest that the HO CDI or HO MRSA BSI were associated with use of a WZM. During this time period, there were 14 cases of community onset (CO) CDI, 2 cases of CO MRSA BSI, and one CO CRE. Conclusion During use of a WZM in COVID cohort units, IP did not identify significant increase in HO CDI, CRE, or MRSA BSI compared to non-cohort units. We were limited in our ability to measure acquisition of pathogens because active surveillance screening for colonization was not performed. However, we were able to safely employ a WZM to streamline patient care in COVID cohort areas without evidence of causing nosocomial infections via patient-to-patient transmission. Disclosures All Authors: No reported disclosures

To assess the prevalence of retinopathy and its association with systemic morbidity and laboratory indices of coagulation and inflammatory dysfunction in severe COVID-19. Retrospective, observational cohort study. Adult patients hospitalized with severe COVID-19 who underwent ophthalmic examination from April to July 2020 were reviewed. Retinopathy was defined as one of the following: 1) Retinal hemorrhage; 2) Cotton wool spots; 3) Retinal vascular occlusion. We analyzed medical comorbidities, sequential organ failure assessment (SOFA) scores, clinical outcomes, and laboratory values for their association with retinopathy. Thirty-seven patients with severe COVID-19 were reviewed, the majority of whom were female (n = 23, 62%), Black (n = 26, 69%), and admitted to the intensive care unit (n = 35, 95%). Fourteen patients had retinopathy (38%) with retinal hemorrhage in 7 (19%), cotton wool spots in 8 (22%), and a branch retinal artery occlusion in 1 (3%) patient. Patients with retinopathy had higher SOFA scores than those without retinopathy (8.0 vs. 5.3, p = .03), higher rates of respiratory failure requiring invasive mechanical ventilation and shock requiring vasopressors (p p = .03). Peak CRP was higher in patients with cotton wool spots versus those without cotton wool spots (354 mg/dL vs. 268 mg/dL, p = .03). Multivariate logistic regression modeling showed an increased risk of retinopathy with higher peak D-dimers (aOR 1.32, 95% CI 1.01–1.73, p = .04) and male sex (aOR 9.6, 95% CI 1.2–75.5, p = .04). Retinopathy in severe COVID-19 was associated with greater systemic disease morbidity involving multiple organs. Given its association with coagulopathy and inflammation, retinopathy may offer insight into disease pathogenesis in patients with severe COVID-19.

In total, 13 facilities changed C. difficile testing to reflexive testing by enzyme immunoassay (EIA) only after a positive nucleic acid-amplification test (NAAT); the standardized infection ratio (SIR) decreased by 46% (range, -12% to -71% per hospital). Changing testing practice greatly influenced a performance metric without changing C. difficile infection prevention practice.

Background Clostridiodes difficile infections (CDI) are a significant cause of morbidity in the early transplant period, with reported incidences in hematopoietic cell transplant (HCT) recipients as high as 33%. Previously published data from our center found that 650 of 781 (83.2%) HCTs performed from 2010 to 2013 had a stool sample submitted for CD testing in the peritransplant setting. Testing identified 86 (13.2%) cases with CDI (12% in autologous and 17.5% in allogeneic HCT recipients), the majority being diagnosed within a week after transplantation. In December of 2018, Infection Control at Emory University Hospital implemented a HCT-unit CD screening policy for all patients upon admission. This review was aimed to assess the effects the new screening policy had on healthcare-facility onset (HO) CDI rates in our transplant population. Methods This is a retrospective review of autologous and allogeneic HCT recipients admitted from January 1, 2019 to July 31, 2019. All HCT patients admitted during this time period were included. Per the CD screening policy, PCR based testing of stool samples would be performed for all patients within 3 calendar days of admission. Patients with positive screens that later develop symptoms of CDI were classified as community-onset (CO), whereas patients with negative or absent screening tests were considered HO if subsequently had positive testing. If positive screened patients developed CDI and had been hospitalized at our facility within the past 4 weeks then they were classified as community-onset healthcare facility-associated (CO-HCFA). Results A total of 210 patients were admitted for transplant during the time frame (155 autologous and 55 allogeneic). The median age was 57.6 years and 55.2% were male. One-hundred forty-three (68.1%) patients were screened within 3 calendar days of admission. Screening identified 20 (14%) positive screens with 15 being autologous HCT. There were 16 additional positive tests identified on days 4 through 30 with 10 being autologous HCT. The 36 cases were classified as 6.2% (13) HO, 8.1% (17) CO and 2.9% (6) CO-HCFA. Conclusion CD screening upon transplant admission allowed our facility to more clearly define the epidemiology of CDIs on our transplant unit. By identifying patients colonized with CD, our faculty reduced the number of CDI that would have historically been classified as HO. As only 68.1% of transplant recipients were screened upon admission, the opportunity exists to improve identification of colonized patients. A full analysis of CDI screening for all patients admitted to the transplant unit, which includes patients receiving chemotherapy and transplant readmissions, is planned for a later date.

AbstractObjective:To determine the effect of an electronic medical record (EMR) nudge at reducing total and inappropriate orders testing for hospital-onset Clostridioides difficile infection (HO-CDI).Design:An interrupted time series analysis of HO-CDI orders 2 years before and 2 years after the implementation of an EMR intervention designed to reduce inappropriate HO-CDI testing. Orders for C. difficile testing were considered inappropriate if the patient had received a laxative or stool softener in the previous 24 hours.Setting:Four hospitals in an academic healthcare network.Patients:All patients with a C. difficile order after hospital day 3.Intervention:Orders for C. difficile testing in patients administered a laxative or stool softener in <24 hours triggered an EMR alert defaulting to cancellation of the order (“nudge”).Results:Of the 17,694 HO-CDI orders, 7% were inappropriate (8% prentervention vs 6% postintervention; P < .001). Monthly HO-CDI orders decreased by 21% postintervention (level-change rate ratio [RR], 0.79; 95% confidence interval [CI], 0.73–0.86), and the rate continued to decrease (postintervention trend change RR, 0.99; 95% CI, 0.98–1.00). The intervention was not associated with a level change in inappropriate HO-CDI orders (RR, 0.80; 95% CI, 0.61–1.05), but the postintervention inappropriate order rate decreased over time (RR, 0.95; 95% CI, 0.93–0.97).Conclusion:An EMR nudge to minimize inappropriate ordering for C. difficile was effective at reducing HO-CDI orders, and likely contributed to decreasing the inappropriate HO-CDI order rate after the intervention.

Objective: Healthcare personnel (HCP) were recruited to provide serum samples, which were tested for antibodies against Ebola or Lassa virus to evaluate for asymptomatic seroconversion. Setting: From 2014 to 2016, 4 patients with Ebola virus disease (EVD) and 1 patient with Lassa fever (LF) were treated in the Serious Communicable Diseases Unit (SCDU) at Emory University Hospital. Strict infection control and clinical biosafety practices were implemented to prevent nosocomial transmission of EVD or LF to HCP. Participants: All personnel who entered the SCDU who were required to measure their temperatures and complete a symptom questionnaire twice daily were eligible. Results: No employee developed symptomatic EVD or LF. EVD and LF antibody studies were performed on sera samples from 42 HCP. The 6 participants who had received investigational vaccination with a chimpanzee adenovirus type 3 vectored Ebola glycoprotein vaccine had high antibody titers to Ebola glycoprotein, but none had a response to Ebola nucleoprotein or VP40, or a response to LF antigens. Conclusions: Patients infected with filoviruses and arenaviruses can be managed successfully without causing occupation-related symptomatic or asymptomatic infections. Meticulous attention to infection control and clinical biosafety practices by highly motivated, trained staff is critical to the safe care of patients with an infection from a special pathogen.

Background:Clostridium difficile infection (CDI) is the most common healthcare-associated infection (HAI) and is often associated with increased medical costs and longer lengths of hospital stay. Previous studies have highlighted that hematopoietic stem cell transplant (HSCT) recipients are at an increased risk for CDI of up to 33% from other hospitalized patients. Studies have also supported the prevalence of asymptomatic colonization with C. difficile among HSCT patients. Asymptomatic colonization with C. difficile is a significant risk factor for transmission of infection to other patients developing hospital onset (HO-CDI). Therefore, targeted infection prevention efforts, such as early identification of patients with community-onset (CO-CDI) and patients with asymptomatic colonization with CDI in HSCT patients, may be effective in reducing the occurrence of HO-CDI. We discuss the CDI admission screening protocol in Emory University Hospital’s (EUH) bone marrow transplant (BMT) unit. Methods: As part of an infection prevention initiative, a CDI screening protocol was implemented in December 2018 for all patients that admitted to the EUH inpatient BMT unit. Upon admission, patients were screened for CO-CDI symptoms, specifically loose or unformed stools. A C. difficile toxin assay PCR would be collected within the first 3 calendar days of admission for all patients screened. Patients with symptoms were placed on isolation precautions pending results of the C. difficile toxin assay. If a patient had a positive C. difficile toxin assay result, isolation precautions would be maintained for the duration of hospitalization regardless of symptoms. Patients who are were unable to produce a stool specimen on the first 3 days of admission were excluded from the screening protocol. Patients with positive C. difficile toxin assay PCRs were classified as CO-CDI and were treated. Results: Since implementation of the CDI screening protocol, 109 CDI events were identified from January 2019 to October 2019. Moreover, 79% of positive C. difficile toxin assays were collected within the first 3 calendar days of admission. HO-CDI has decreased from 78% in 2018 to 21% during the designated time frame. Conclusions: CDI screening upon admission of BMT populations has shown a decrease among HO-CDI by early identification of CO-CDI and CO asymptomatic colonization with C. difficile. This early identification has allowed rapid implementation of infection preventions precautions, thus reducing risk of unit-based transmission.Funding: NoneDisclosures: None

Background: Hospital-acquired methicillin-resistant Staphylococcus aureus bloodstream infections (MRSA BSIs) are associated with serious morbidity and mortality in immunocompromised patients. Of all MRSA BSIs at our academic medical center, 63% occurred in the oncology units. A multidisciplinary team was formed to address the improvement opportunity: the clinical nurse specialist, hospital epidemiologist, unit leaders, nurse champions and representatives from infection prevention, pharmacy and information technology. The goal was to decrease the incidence of hospital-onset MRSA BSI in the oncology wards by 10 infections in 2016 by implementing daily chlorohexidine (CHG) bathing and weekly nasal povidone-iodine antisepsis in July 2016. Methods: The strategically targeting oncology with povidone-iodine nasal antisepsis and bathing with CHG Staph reduction initiative (STOP-BSI) was a quality improvement project consisting of daily CHG baths for all oncology patients and nasal povidone-iodine on admission and weekly thereafter. Nurses and patient care technicians were trained on how to administer CHG treatments. Education was also provided to patients on how to use CHG bath wipes to self-administer the nasal antisepsis. Education resources were created to help answer concerns of the staff, patient, or family, and an escalation process was developed for treatment refusal. CHG bath audits were performed to measure compliance and to identify barriers to the process. Results: By the end of 2016, the number of infections decreased by 5 on the oncology units. The number of infections continued to decrease each year. The bone marrow transplant (BMT) unit decreased from 8 infections in 2015 to 3 in 2018. The hematology oncology unit infections decreased from 5 infections in 2015 to 0 in 2018. The medical oncology unit infections decreased from 2 infections in 2015 to 0 in 2018. The CLABSI rates per 1,000 line days trended downward after some time. Conclusions: Implementing daily CHG baths and weekly povidone-iodine nasal antisepsis reduced the number of MRSA BSI infections in the oncology population. The CLABSI rates decreased after barriers to the process were removed.Funding: NoneDisclosures: None

Background: US hospitals are required to report C. difficile infections (CDIs) to the NHSN as a performance measure tied to payment penalties for poor scores. Currently, only the charted CDI test results performed last in reflex testing scenarios are reported to the NHSN (CDI events). We describe the reduction in NHSN CDI events from the addition of a reflex toxin enzyme immunoassay (EIA) after a positive nucleic acid amplification test (NAAT) in teaching and nonteaching hospitals, and we estimate the impact on standardized infection ratios (SIR). Methods: Reporting of all CDI test results, by test method, occurred during April 2018–July 2019 to the Georgia Emerging Infections program (funded by the Centers for Disease Control and Prevention), which conducts active population-based surveillance in an 8-county Atlanta area (population, 4 million). Among facilities starting reflex EIA testing, results were aggregated by test method during months of reflex testing to calculate facility-specific reduction in NHSN CDI events (% reduction; 1-[no. EIA+/no. NAAT+]). Differences in percent reduction between facilities by characteristic were compared using the Kruskal-Wallis test. We simulated expected changes in the SIR for a range of reductions, assuming equal effect on both community-onset (CO) and hospital-onset (HO) tests. Each facility’s historical NHSN CDI events prior to reflex testing were used to estimate changes to facility-specific SIRs by reducing values by the corresponding facility’s percent reduction. Results: Overall, 13 acute-care hospitals (bed size, 52–633; ICU bed size, 6–105) started reflex testing during the study period (mean, 7 months, 15,800 admissions, 66,400 patient days), resulting in 550 +NAAT tests reflexing to 180 +EIA tests (pooled mean 58% reduction). Percent reduction varied (mean, 67%; range, 42%–81%) but did not differ between larger (≥217 beds) and smaller hospitals (61 vs 50% reduction; P > .05) or by outsourced versus inhouse testing (65% vs 54% reduction; P > .05). Simulations identified a threshold reduction at which point effect on HO counteract the effects on CO events enough to reduce the SIR; thresholds for nonteaching and teaching were 26% and 32% reduction, respectively (Fig. 1). The estimated reductions in facility-specific SIRs using measured percent reductions on historic NHSN CDI events closely paralleled the simulation, and the mean estimated change in SIR was −46% (range, −12% to −71%) (Fig. 1). Conclusions: Although the magnitude of the effect varied, all 13 facilities experienced dramatic reductions in CDI events reportable to NHSN due to reflex testing; applying these reductions to historical NHSN data illustrates anticipated reductions in their facility-specific SIRs due to this testing change.Funding: NoneDisclosures: Scott Fridkin, consulting fee, vaccine industry (various) (spouse)

Ebola virus disease (EVD) is associated with elevated cytokine levels, and hypercytokinemia is more pronounced in fatal cases. This type of hyperinflammatory state is reminiscent of 2 rheumatologic disorders known as macrophage activation syndrome and hemophagocytic lymphohistiocytosis, which are characterized by macrophage and T-cell activation. An evaluation of 2 cohorts of patients with EVD revealed that a marker of macrophage activation (sCD163) but not T-cell activation (sCD25) was associated with severe and fatal EVD. Furthermore, substantial immunoreactivity of host tissues to a CD163-specific antibody, predominantly in areas of extensive immunostaining for Ebola virus antigens, was observed in fatal cases. These data suggest that host macrophage activation contributes to EVD pathogenesis and that directed antiinflammatory therapies could be beneficial in the treatment of EVD.

Ebola virus disease (EVD) is associated with elevated cytokine levels, and hypercytokinemia is more pronounced in fatal cases. This type of hyperinflammatory state is reminiscent of 2 rheumatologic disorders known as macrophage activation syndrome and hemophagocytic lymphohistiocytosis, which are characterized by macrophage and T-cell activation. An evaluation of 2 cohorts of patients with EVD revealed that a marker of macrophage activation (sCD163) but not T-cell activation (sCD25) was associated with severe and fatal EVD. Furthermore, substantial immunoreactivity of host tissues to a CD163-specific antibody, predominantly in areas of extensive immunostaining for Ebola virus antigens, was observed in fatal cases. These data suggest that host macrophage activation contributes to EVD pathogenesis and that directed antiinflammatory therapies could be beneficial in the treatment of EVD.

We describe a strain of Lassa virus representing a putative new lineage that was isolated from a cluster of human infections with an epidemiologic link to Togo. This finding extends the known range of Lassa virus to Togo.

We describe a strain of Lassa virus representing a putative new lineage that was isolated from a cluster of human infections with an epidemiologic link to Togo. This finding extends the known range of Lassa virus to Togo.