Stefan Schilling

Rapid Detection and Quantification of RNA of Ebola and Marburg Viruses, Lassa Virus, Crimean-Congo Hemorrhagic Fever Virus, Rift Valley Fever Virus, Dengue Virus, and Yellow Fever Virus by Real-Time Reverse Transcription-PCR

ABSTRACT Viral hemorrhagic fevers (VHFs) are acute infections with high case fatality rates. Important VHF agents are Ebola and Marburg viruses (MBGV/EBOV), Lassa virus (LASV), Crimean-Congo hemorrhagic fever virus (CCHFV), Rift Valley fever virus (RVFV), dengue virus (DENV), and yellow fever virus (YFV). VHFs are clinically difficult to diagnose and to distinguish; a rapid and reliable laboratory diagnosis is required in suspected cases. We have established six one-step, real-time reverse transcription-PCR assays for these pathogens based on the Superscript reverse transcriptase-Platinum Taq polymerase enzyme mixture. Novel primers and/or 5′-nuclease detection probes were designed for RVFV, DENV, YFV, and CCHFV by using the latest DNA database entries. PCR products were detected in real time on a LightCycler instrument by using 5′-nuclease technology (RVFV, DENV, and YFV) or SybrGreen dye intercalation (MBGV/EBOV, LASV, and CCHFV). The inhibitory effect of SybrGreen on reverse transcription was overcome by initial immobilization of the dye in the reaction capillaries. Universal cycling conditions for SybrGreen and 5′-nuclease probe detection were established. Thus, up to three assays could be performed in parallel, facilitating rapid testing for several pathogens. All assays were thoroughly optimized and validated in terms of analytical sensitivity by using in vitro-transcribed RNA. The ≥95% detection limits as determined by probit regression analysis ranged from 1,545 to 2,835 viral genome equivalents/ml of serum (8.6 to 16 RNA copies per assay). The suitability of the assays was exemplified by detection and quantification of viral RNA in serum samples of VHF patients.

Hantavirus Disease Outbreak in Germany: Limitations of Routine Serological Diagnostics and Clustering of Virus Sequences of Human and Rodent Origin

ABSTRACT In Europe, hemorrhagic fever with renal syndrome results mainly from infection with Puumala virus (PUUV) or Dobrava virus. For 31 patients from a hantavirus disease outbreak in Lower Bavaria, a district in southeast Germany, serodiagnosis was undertaken by enzyme-linked immunosorbent assay, immunofluorescence assay, and immunoblot analysis. In a few of these cases, however, PUUV-specific typing of antibodies by these standard assays failed and a virus neutralization assay under biosafety level 3 conditions was required to verify the infection by this virus type. PUUV RNA was amplified by reverse transcription-PCR from acute-phase sera of three patients and was found to be very closely related to virus sequences obtained from bank voles (Clethrionomys glareolus) trapped in the same area. These findings link the outbreak with a novel PUUV lineage, “Bavaria,” circulating in the local rodent population. The Bavaria lineage associated with the outbreak is only distantly related to other PUUV lineages from Germany.

Serological Differentiation of Infections with Dengue Virus Serotypes 1 to 4 by Using Recombinant Antigens

ABSTRACT The B domains of dengue virus serotypes 1 to 4 were expressed in Escherichia coli. The purified proteins were applied to immunoblot strips to detect serotype-specific antibodies in paired serum samples from 41 patients with primary and secondary dengue infections. A close correlation between the results obtained with the immunoblot strips and by type-specific reverse transcription-PCR (T. Laue, P. Emmerich, and H. Schmitz, J. Clin. Microbiol. 37:2543-2547, 1999) was observed.

Acute liver failure, multiorgan failure, cerebral oedema, and activation of proangiogenic and antiangiogenic factors in a case of Marburg haemorrhagic fever

A woman developed Marburg haemorrhagic fever in the Netherlands, most likely as a consequence of being exposed to virus-infected bats in the python cave in Maramagambo Forest during a visit to Uganda. The clinical syndrome was dominated by acute liver failure with secondary coagulopathy, followed by a severe systemic inflammatory response, multiorgan failure, and fatal cerebral oedema. A high blood viral load persisted during the course of the disease. The initial systemic inflammatory response coincided with peaks in interferon-γ and tumour necrosis factor-α concentrations in the blood. A terminal rise in interleukin-6, placental growth factor (PlGF), and soluble vascular endothelial growth factor receptor-1 (sVEGF-R1) seemed to suggest an advanced pathophysiological stage of Marburg haemorrhagic fever associated with vascular endothelial dysfunction and fatal cerebral oedema. The excess of circulating sVEGF-R1 and the high sVEGF-R1:PlGF ratio shortly before death resemble pathophysiological changes thought to play a causative part in pre-eclampsia. Aggressive critical-care treatment with renal replacement therapy and use of the molecular absorbent recirculation system appeared able to stabilise--at least temporarily--the patients condition.

Infection control management of patients with suspected highly infectious diseases in emergency departments: data from a survey in 41 facilities in 14 European countries

BackgroundIn Emergency and Medical Admission Departments (EDs and MADs), prompt recognition and appropriate infection control management of patients with Highly Infectious Diseases (HIDs, e.g. Viral Hemorrhagic Fevers and SARS) are fundamental for avoiding nosocomial outbreaks.MethodsThe EuroNHID (European Network for Highly Infectious Diseases) project collected data from 41 EDs and MADs in 14 European countries, located in the same facility as a national/regional referral centre for HIDs, using specifically developed checklists, during on-site visits from February to November 2009.ResultsIsolation rooms were available in 34 facilities (82,9%): these rooms had anteroom in 19, dedicated entrance in 15, negative pressure in 17, and HEPA filtration of exhausting air in 12. Only 6 centres (14,6%) had isolation rooms with all characteristics. Personnel trained for the recognition of HIDs was available in 24 facilities; management protocols for HIDs were available in 35.ConclusionsPreparedness level for the safe and appropriate management of HIDs is partially adequate in the surveyed EDs and MADs.

EuroNHID checklists for the assessment of high‐level isolation units and referral centres for highly infectious diseases: results from the pilot phase of a European survey

Healthcare settings have been identified as preferential for the transmission of many agents causing highly infectious diseases (HIDs). Infection control procedures strongly reduce the risk of transmission of HIDs in hospital settings, when adequately applied. The main objective of the European Network for Highly Infectious Diseases (EuroNHID), a network co-funded by the European Commission, is to assess the current capabilities for dealing with HIDs in Europe, specifically in the context of infection control and healthcare worker (HCW) safety, through conducting an on-the-field survey of high-level isolation units (HLIUs)/referral centres for the management of HIDs in participating countries. During the first year of the projects activities, specifically designed, evidence-based checklists were developed. This review introduces the EuroNHID checklists as a standard tool for the assessment of hospital capabilities concerning infection control and HCW safety in the management of patients with HIDs, and presents preliminary results from five HLIUs.

Infection control practices in facilities for highly infectious diseases across Europe

Summary Background The management of patients with highly infectious diseases (HIDs) is a challenge for healthcare provision requiring a high level of care without compromising the safety of other patients and healthcare workers. Aim To study the infection control practice in isolation facilities participating in the European Network for Highly Infectious Diseases (EuroNHID) project. Methods A survey was conducted during 2009 of 48 isolation facilities caring for patients with HIDs in 16 European countries. Checklists and standard evaluation forms were used to collect and interpret data on hand hygiene, routine hygiene and disinfection, and waste management. Findings Forty percent of HIDs had no non-hand-operated sinks or alcohol-based antiseptic distributors, while 27% did not have procedures for routine hygiene, final disinfection, or safe discarding of non-disposable objects or equipment. There was considerable variation in the management of waste and in the training of housekeeping personnel. EuroNHID has developed recommendations for hand hygiene, disinfection, routine hygiene, and waste management. Conclusions Most aspects of hand hygiene, routine hygiene and disinfection, and waste management were considered at least partially adequate in the majority of European isolation facilities dedicated for the care of patients with HIDs. But considerable variability was observed, with management of waste and training of housekeeping personnel being generally less satisfactory.

European concepts for the domestic transport of highly infectious patients

Highly infectious diseases involve clinical syndromes ranging from single to multiorgan infections and pose a constant threat to the public. In the absence of a definite treatment for most causative agents, patients benefit from maximum supportive care as clinical conditions may deteriorate in the short term. Hence, following initial case identification and isolation, rapid transportation to a specialized treatment unit must be considered in order to minimize the risk of secondary infections, but this is limited by available infrastructure, accessible care en route and the patients clinical condition. Despite the development of consensus curricula for the clinical management of highly infectious patients, medical transportation lacks a common European approach. This article describes, as examples, three current European concepts for the domestic relocation of highly infectious patients by ground vehicles and aircraft with respect to national legislation and geography.

Continued vigilance – development of an online evaluation tool for assessing preparedness of medical facilities for biological events

Objective: Effective response to biological events necessitates ongoing evaluation of preparedness. This study was a bilateral German–Israeli collaboration aimed at developing an evaluation tool for assessing preparedness of medical facilities for biological events. Methods: Measurable parameters were identified through a literature review for inclusion in the evaluation tool and disseminated to 228 content experts in two modified Delphi cycles. Focus groups were conducted to identify psychosocial needs of the medical teams. Table-top and functional exercises were implemented to review applicability of the tool. Results: One hundred seventeen experts from Germany and Israel participated in the modified Delphi. Out of 188 parameters that were identified, 183 achieved a consensus of >75% of the content experts. Following comments recommended in the Delphi cycles, and feedback from focus groups and hospital exercises, the final tool consisted of 172 parameters. Median level of importance of each parameter was calculated based on ranking recommended in the Delphi process. Computerized web-based software was developed to calculate scores of preparedness for biological events. Conclusion: Ongoing evaluation means, such as the tool developed in the study, can facilitate the need for a valid and reliable mechanism that may be widely adopted and implemented as quality assurance measures. The tool is based on measurable parameters and indicators that can effectively present strengths and weaknesses in managing a response to a public health threat, and accordingly, steps can be implemented to improve readiness. Adoption of such a tool is an important component of assuring public health and effective emergency management.

Diagnostic issues and capabilities in 48 isolation facilities in 16 European countries: data from EuroNHID surveys

BackgroundHighly infectious diseases (HIDs) are defined as being transmissible from person to person, causing life-threatening illnesses and presenting a serious public health hazard. The sampling, handling and transport of specimens from patients with HIDs present specific bio-safety concerns.FindingsThe European Network for HID project aimed to record, in a cross-sectional study, the infection control capabilities of referral centers for HIDs across Europe and assesses the level of achievement to previously published guidelines. In this paper, we report the current diagnostic capabilities and bio-safety measures applied to diagnostic procedures in these referral centers. Overall, 48 isolation facilities in 16 European countries were evaluated. Although 81% of these referral centers are located near a biosafety level 3 laboratory, 11% and 31% of them still performed their microbiological and routine diagnostic analyses, respectively, without bio-safety measures.ConclusionsThe discrepancies among the referral centers surveyed between the level of practices and the European Network of Infectious Diseases (EUNID) recommendations have multiple reasons of which the interest of the individuals in charge and the investment they put in preparedness to emerging outbreaks. Despite the fact that the less prepared centers can improve by just updating their practice and policies any support to help them to achieve an acceptable level of biosecurity is welcome.