Stefan Schmiedel

A Case of Severe Ebola Virus Infection Complicated by Gram-Negative Septicemia

Ebola virus disease (EVD) developed in a patient who contracted the disease in Sierra Leone and was airlifted to an isolation facility in Hamburg, Germany, for treatment. During the course of the illness, he had numerous complications, including septicemia, respiratory failure, and encephalopathy. Intensive supportive treatment consisting of high-volume fluid resuscitation (approximately 10 liters per day in the first 72 hours), broad-spectrum antibiotic therapy, and ventilatory support resulted in full recovery without the use of experimental therapies. Discharge was delayed owing to the detection of viral RNA in urine (day 30) and sweat (at the last assessment on day 40) by means of polymerase-chain-reaction (PCR) assay, but the last positive culture was identified in plasma on day 14 and in urine on day 26. This case shows the challenges in the management of EVD and suggests that even severe EVD can be treated effectively with routine intensive care.

Phase 1 Trials of rVSV Ebola Vaccine in Africa and Europe.

BACKGROUND The replication-competent recombinant vesicular stomatitis virus (rVSV)-based vaccine expressing a Zaire ebolavirus (ZEBOV) glycoprotein was selected for rapid safety and immunogenicity testing before its use in West Africa. METHODS We performed three open-label, dose-escalation phase 1 trials and one randomized, double-blind, controlled phase 1 trial to assess the safety, side-effect profile, and immunogenicity of rVSV-ZEBOV at various doses in 158 healthy adults in Europe and Africa. All participants were injected with doses of vaccine ranging from 300,000 to 50 million plaque-forming units (PFU) or placebo. RESULTS No serious vaccine-related adverse events were reported. Mild-to-moderate early-onset reactogenicity was frequent but transient (median, 1 day). Fever was observed in up to 30% of vaccinees. Vaccine viremia was detected within 3 days in 123 of the 130 participants (95%) receiving 3 million PFU or more; rVSV was not detected in saliva or urine. In the second week after injection, arthritis affecting one to four joints developed in 11 of 51 participants (22%) in Geneva, with pain lasting a median of 8 days (interquartile range, 4 to 87); 2 self-limited cases occurred in 60 participants (3%) in Hamburg, Germany, and Kilifi, Kenya. The virus was identified in one synovial-fluid aspirate and in skin vesicles of 2 other vaccinees, showing peripheral viral replication in the second week after immunization. ZEBOV-glycoprotein-specific antibody responses were detected in all the participants, with similar glycoprotein-binding antibody titers but significantly higher neutralizing antibody titers at higher doses. Glycoprotein-binding antibody titers were sustained through 180 days in all participants. CONCLUSIONS In these studies, rVSV-ZEBOV was reactogenic but immunogenic after a single dose and warrants further evaluation for safety and efficacy. (Funded by the Wellcome Trust and others; ClinicalTrials.gov numbers, NCT02283099, NCT02287480, and NCT02296983; Pan African Clinical Trials Registry number, PACTR201411000919191.).

Comprehensive Analysis of Frequency and Phenotype of T Regulatory Cells in HIV Infection: CD39 expression of FoxP3+ T regulatory cells correlates with progressive disease.

ABSTRACT There are conflicting data about the frequency and role of regulatory T cells (Tregs) during the course of HIV infection. Peripheral blood of a large cohort of HIV-infected patients (n = 131) at different stages of disease, including 15 long-term nonprogressors and 21 elite controllers, was analyzed to determine the frequency and phenotype of Tregs, defined as CD4+, CD25high, CD127low, FoxP3high cells. A significantly increased relative frequency of Tregs within the CD4+ compartment of HIV+ patients compared to that of healthy controls (P < 0.0001) was observed. Additionally, the relative frequency of Tregs directly correlated with HIV viral load and inversely with CD4+ counts. However, the absolute Treg number was reduced in HIV-infected patients versus healthy controls (P < 0.0001), with the exception of elite controllers (P > 0.05). The loss of absolute Treg numbers coincided with rising markers of immune activation (P < 0.0006). The initiation of antiviral therapy significantly increased absolute Treg numbers (P < 0.0031). We find that the expression of CD39, a newly defined ectonucleotidase with immunomodulatory functions on Tregs, correlated with progressive HIV disease, HIV viral load, and immune activation. Of note, when tested in peripheral blood mononuclear cells of healthy volunteers, the in vitro capacity to suppress T-cell proliferation was limited to CD4+, CD25high, CD39+ T cells. Interestingly, Tregs of elite controllers exhibited not only the highest expression of CCR5, CTLA-4, and ICOS but also the lowest level of CD39. The data presented here reconcile the seemingly contradictory results of previous studies looking at Tregs in HIV and highlight the complexity of Treg-mediated immunoregulation during human viral infections.

Clinical Management of Ebola Virus Disease in the United States and Europe

BACKGROUND Available data on the characteristics of patients with Ebola virus disease (EVD) and clinical management of EVD in settings outside West Africa, as well as the complications observed in those patients, are limited. METHODS We reviewed available clinical, laboratory, and virologic data from all patients with laboratory-confirmed Ebola virus infection who received care in U.S. and European hospitals from August 2014 through December 2015. RESULTS A total of 27 patients (median age, 36 years [range, 25 to 75]) with EVD received care; 19 patients (70%) were male, 9 of 26 patients (35%) had coexisting conditions, and 22 (81%) were health care personnel. Of the 27 patients, 24 (89%) were medically evacuated from West Africa or were exposed to and infected with Ebola virus in West Africa and had onset of illness and laboratory confirmation of Ebola virus infection in Europe or the United States, and 3 (11%) acquired EVD in the United States or Europe. At the onset of illness, the most common signs and symptoms were fatigue (20 patients [80%]) and fever or feverishness (17 patients [68%]). During the clinical course, the predominant findings included diarrhea, hypoalbuminemia, hyponatremia, hypokalemia, hypocalcemia, and hypomagnesemia; 14 patients (52%) had hypoxemia, and 9 (33%) had oliguria, of whom 5 had anuria. Aminotransferase levels peaked at a median of 9 days after the onset of illness. Nearly all the patients received intravenous fluids and electrolyte supplementation; 9 (33%) received noninvasive or invasive mechanical ventilation; 5 (19%) received continuous renal-replacement therapy; 22 (81%) received empirical antibiotics; and 23 (85%) received investigational therapies (19 [70%] received at least two experimental interventions). Ebola viral RNA levels in blood peaked at a median of 7 days after the onset of illness, and the median time from the onset of symptoms to clearance of viremia was 17.5 days. A total of 5 patients died, including 3 who had respiratory and renal failure, for a mortality of 18.5%. CONCLUSIONS Among the patients with EVD who were cared for in the United States or Europe, close monitoring and aggressive supportive care that included intravenous fluid hydration, correction of electrolyte abnormalities, nutritional support, and critical care management for respiratory and renal failure were needed; 81.5% of these patients who received this care survived.

Management of Accidental Exposure to Ebola Virus in the Biosafety Level 4 Laboratory, Hamburg, Germany

A needlestick injury occurred during an animal experiment in the biosafety level 4 laboratory in Hamburg, Germany, in March 2009. The syringe contained Zaire ebolavirus (ZEBOV) mixed with Freunds adjuvant. Neither an approved treatment nor a postexposure prophylaxis (PEP) exists for Ebola hemorrhagic fever. Following a risk-benefit assessment, it was recommended the exposed person take an experimental vaccine that had shown PEP efficacy in ZEBOV-infected nonhuman primates (NHPs) [12]. The vaccine, which had not been used previously in humans, was a live-attenuated recombinant vesicular stomatitis virus (recVSV) expressing the glycoprotein of ZEBOV. A single dose of 5 × 10(7) plaque-forming units was injected 48 hours after the accident. The vaccinee developed fever 12 hours later and recVSV viremia was detectable by polymerase chain reaction (PCR) for 2 days. Otherwise, the person remained healthy, and ZEBOV RNA, except for the glycoprotein gene expressed in the vaccine, was never detected in serum and peripheral blood mononuclear cells during the 3-week observation period.

Absence of Erythrocyte Sequestration and Lack of Multicopy Gene Family Expression in Plasmodium falciparum from a Splenectomized Malaria Patient

Background To avoid spleen-dependent killing mechanisms parasite-infected erythrocytes (IE) of Plasmodium falciparum malaria patients have the capacity to bind to endothelial receptors. This binding also known as sequestration, is mediated by parasite proteins, which are targeted to the erythrocyte surface. Candidate proteins are those encoded by P. falciparum multicopy gene families, such as var, rif, stevor or PfMC-2TM. However, a direct in vivo proof of IE sequestration and expression of multicopy gene families is still lacking. Here, we report on the analysis of IE from a black African immigrant, who received the diagnosis of a malignant lymphoproliferative disorder and subsequently underwent splenectomy. Three weeks after surgery, the patient experienced clinical falciparum malaria with high parasitemia and circulating developmental parasite stages usually sequestered to the vascular endothelium such as late trophozoites, schizonts or immature gametocytes. Methodology/Principal Findings Initially, when isolated from the patient, the infected erythrocytes were incapable to bind to various endothelial receptors in vitro. Moreover, the parasites failed to express the multicopy gene families var, A-type rif and stevor but expression of B-type rif and PfMC-2TM genes were detected. In the course of in vitro cultivation, the parasites started to express all investigated multicopy gene families and concomitantly developed the ability to adhere to endothelial receptors such as CD36 and ICAM-1, respectively. Conclusion/Significance This case strongly supports the hypothesis that parasite surface proteins such as PfEMP1, A-type RIFIN or STEVOR are involved in interactions of infected erythrocytes with endothelial receptors mediating sequestration of mature asexual and immature sexual stages of P. falciparum. In contrast, multicopy gene families coding for B-type RIFIN and PfMC-2TM proteins may not be involved in sequestration, as these genes were transcribed in infected but not sequestered erythrocytes.

Unique human immune signature of Ebola virus disease in Guinea

Despite the magnitude of the Ebola virus disease (EVD) outbreak in West Africa, there is still a fundamental lack of knowledge about the pathophysiology of EVD. In particular, very little is known about human immune responses to Ebola virus. Here we evaluate the physiology of the human T cell immune response in EVD patients at the time of admission to the Ebola Treatment Center in Guinea, and longitudinally until discharge or death. Through the use of multiparametric flow cytometry established by the European Mobile Laboratory in the field, we identify an immune signature that is unique in EVD fatalities. Fatal EVD was characterized by a high percentage of CD4+ and CD8+ T cells expressing the inhibitory molecules CTLA-4 and PD-1, which correlated with elevated inflammatory markers and high virus load. Conversely, surviving individuals showed significantly lower expression of CTLA-4 and PD-1 as well as lower inflammation, despite comparable overall T cell activation. Concomitant with virus clearance, survivors mounted a robust Ebola-virus-specific T cell response. Our findings suggest that dysregulation of the T cell response is a key component of EVD pathophysiology.

Artesunate versus quinine in the treatment of severe imported malaria: comparative analysis of adverse events focussing on delayed haemolysis

BackgroundSevere malaria is a potentially life-threatening infectious disease. It has been conclusively shown that artesunate compared to quinine is superior in antiparasitic efficacy and in lowering mortality showing a better short-term safety profile. Regarding longer-term effects, reports of delayed haemolysis after parenteral artesunate for severe malaria in returning travellers have been published recently. So far, delayed haemolysis has not been described after the use of parenteral quinine.MethodsIn this retrospective study, all patients treated for severe malaria at the University Medical Centre Hamburg-Eppendorf were included between 2006 and 2012. The primary endpoint was the proportion of delayed haemolysis in patients treated with quinine versus those who received artesunate. As secondary endpoint, the proportion of any adverse event was assessed.ResultsA total of 36 patients with severe malaria were included in the analysis. Of these, 16 patients contributed sufficient data to assess the endpoint delayed haemolysis. Twelve were treated primarily with intravenous quinine – with four patients having received intrarectal artesunate as an adjunct treatment – and five patients were treated primarily with artesunate. Five cases of delayed haemolysis could be detected – two in patients treated with quinine and intrarectal artesunate and three in patients treated with artesunate. No case of delayed haemolysis was detected in patients treated with quinine alone.While adverse events observed in patients treated with artesunate were limited to delayed haemolysis (three patients, 60%) and temporary deterioration in renal function (three patients, 60%), patients treated with quinine showed a more diverse picture of side effects with 22 patients (71%) experiencing at least one adverse event. The most common adverse events after quinine were hearing disturbances (12 patients, 37%), hypoglycaemia (10 patients, 32%) and cardiotoxicity (three patients, 14%).ConclusionsThis study provides further evidence on delayed haemolysis after artesunate and underlines the importance of a standardized follow-up of patients treated with artesunate for severe malaria.

Post-treatment haemolysis in severe imported malaria after intravenous artesunate: case report of three patients with hyperparasitaemia.

Parenteral artesunate has been shown to be a superior treatment option compared to parenteral quinine in adults and children with severe malaria. Little evidence, however, is available on long-term safety. Recently, cases of late-onset haemolysis after parenteral treatment with artesunate have been reported in European travellers with imported Plasmodium falciparum malaria. Therefore, an extended follow-up of adult patients treated for severe imported malaria was started in August 2011 at the University Medical Center Hamburg-Eppendorf. Until January 2012, three patients with hyperparasitaemia (range: 14-21%) were included for analysis. In all three patients, delayed haemolysis was detected in the second week after the first dose of intravenous artesunate. Reticulocyte production index remained inadequately low in the 7 – 14 days following the first dose of artesunate despite rapid parasite clearance. Post-treatment haemolysis after parenteral artesunate may be of clinical relevance in particular in imported severe malaria characterized by high parasite levels. Extended follow-up of at least 30 days including controls of haematological parameters after artesunate treatment seems to be indicated. Further investigations are needed to assess frequency and pathophysiological background of this complication.

Reduced cardiac output in imported Plasmodium falciparum malaria

BackgroundVolume substitution remains subject of controversy in the light of effusions and oedema potentially complicating this highly febrile disease. Understanding the role of myocardial and circulatory function appears to be essential for clinical management. In the present study, cardiac function and cardiac proteins have been assessed and correlated with parasitological and immunologic parameters in patients with imported Plasmodium falciparum malaria.MethodsIn a prospective case-control study, 28 patients with uncomplicated and complicated P. falciparum malaria were included and findings were compared with 26 healthy controls. Cardiac function parameters were assessed by an innovative non-invasive method based on the re-breathing technique. In addition, cardiac enzymes and pro- and anti-inflammatory cytokines were measured and assessed with respect to clinical symptoms and conditions of malaria.ResultsCardiac index (CI) as a measurement of cardiac output (CO) was 21% lower in malaria patients than in healthy controls (2.7 l/min/m2versus 3.4 l/min/m2; P < 0.001). In contrast, systemic vascular resistance index (SVRI) was increased by 29% (32.6 mmHg⋅m2/(l/min) versus 23.2 mmHg⋅m2/(l/min); P < 0.001). This correlated with increased cardiac proteins in patients versus controls: pro-BNP 139.3 pg/ml versus 60.4 pg/ml (P = 0.03), myoglobin 43.6 μg/l versus 27.8 μg/l (P = < 0.001). All measured cytokines were significantly increased in patients with malaria. CI, SVRI as well as cytokine levels did not correlate with blood parasite density.ConclusionsThe results support previous reports suggesting impaired cardiac function contributing to clinical manifestations in P. falciparum malaria. Findings may be relevant for fluid management and should be further explored in endemic regions.