Investigation of a Limited but Explosive COVID-19 Outbreak in a German Secondary School.

The role of schools as a source of infection and driver in the coronavirus-pandemic has been controversial and is still not completely clarified. To prevent harm and disadvantages for children and adolescents, but also adults, detailed data on school outbreaks is needed, especially when talking about open schools employing evidence-based safety concepts. Here, we investigated the first significant COVID-19 school outbreak in Hamburg, Germany, after the re-opening of schools in 2020.

SARS-CoV-2 Aerosol Transmission Indoors: A Closer Look at Viral Load, Infectivity, the Effectiveness of Preventive Measures and a Simple Approach for Practical Recommendations.

There is uncertainty about the viral loads of infectious individuals required to transmit COVID-19 via aerosol. In addition, there is a lack of both quantification of the influencing parameters on airborne transmission and simple-to-use models for assessing the risk of infection in practice, which furthermore quantify the influence of non-medical preventive measures. In this study, a dose-response model was adopted to analyze 25 documented outbreaks at infection rates of 4-100%.

Description of measles D4-Hamburg outbreak in Hamburg, Germany, December 2008 to June 2009, which disproportionally affected a local Roma community.

From December 2008 to June 2009 a measles outbreak occurred in the Federal State of Hamburg, Germany. The outbreak affected 216 persons and was caused by a new measles strain termed D4-Hamburg which led to consecutive outbreaks between 2009 and 2011 in at least 12 European countries. Here, we describe epidemiological characteristics of the outbreak and evaluate the control measures taken in Hamburg.

Genetic variation and recombination in Aichi virus.

Aichi virus (AiV), a member of the genus Kobuvirus in the family Picornaviridae, causes gastroenteritis in humans. It was noted that AiV differs from other picornaviruses in its unusually high C content and a very high degree of genome-ordered RNA secondary structures. However, the genetic variability and mutational restrictions on a full-genome scale have not been studied.

Human cardioviruses, meningitis, and sudden infant death syndrome in children.

Cardioviruses cause myocarditis and encephalomyelitis in rodents; human cardioviruses have not been ascribed to any disease. We screened 6,854 cerebrospinal fluid and 10 myocardium specimens from children and adults. A genotype 2 cardiovirus was detected from a child who died of sudden infant death syndrome, and 2 untypeable cardioviruses were detected from 2 children with meningitis.

Aichi virus shedding in high concentrations in patients with acute diarrhea.

We assessed Aichi virus shedding in patients with gastroenteritis and negative test results for other viral and bacterial infections. High concentrations of up to 1.32 × 1012 RNA copies/g stool were found in 10 (2.

Spread of measles virus D4-Hamburg, Europe, 2008-2011.

A new strain of measles virus, D4-Hamburg, was imported from London to Hamburg in December 2008 and subsequently spread to Bulgaria, where an outbreak of >24,300 cases was observed. We analyzed spread of the virus to demonstrate the importance of addressing hard-to-reach communities within the World Health Organization European Region regarding access to medical care and vaccination campaigns. The D4-Hamburg strain appeared during 2009-2011 in Poland, Ireland, Northern Ireland, Austria, Greece, Romania, Turkey, Macedonia, Serbia, Switzerland, and Belgium and was repeatedly reimported to Germany.

Differential host determinants contribute to the pathogenesis of 2009 pandemic H1N1 and human H5N1 influenza A viruses in experimental mouse models.

Influenza viruses are responsible for high morbidities in humans and may, eventually, cause pandemics. Herein, we compared the pathogenesis and host innate immune responses of a seasonal H1N1, two 2009 pandemic H1N1, and a human H5N1 influenza virus in experimental BALB/c and C57BL/6J mouse models. We found that both 2009 pandemic H1N1 isolates studied (A/Hamburg/05/09 and A/Hamburg/NY1580/09) were low pathogenic in BALB/c mice [log mouse lethal dose 50 (MLD(50)) >6 plaque-forming units (PFU)] but displayed remarkable differences in virulence in C57BL/6J mice.

Differential use of importin-α isoforms governs cell tropism and host adaptation of influenza virus.

Influenza A viruses are a threat to humans due to their ability to cross species barriers, as illustrated by the 2009 H1N1v pandemic and sporadic H5N1 transmissions. Interspecies transmission requires adaptation of the viral polymerase to importin-α, a cellular protein that mediates transport into the nucleus where transcription and replication of the viral genome takes place. In this study, we analysed replication, host specificity and pathogenicity of avian and mammalian influenza viruses, in importin-α-silenced cells and importin-α-knockout mice, to understand the role of individual importin-α isoforms in adaptation.

Comparative analysis of rabies virus reverse transcription-PCR and virus isolation using samples from a patient infected with rabies virus.

Definite and rapid diagnosis of rabies is required for individual case management as well as for public health. For the first time, a direct comparison of virus isolation with quantitative real-time reverse transcription (RT)-PCR on human rabies samples was conducted. RT-PCR was found to be more sensitive than virus isolation.

Management and outcomes after multiple corneal and solid organ transplantations from a donor infected with rabies virus.

Background: This article describes multiple transmissions of rabies via transplanted solid organ from a single infected donor. The empirical Milwaukee treatment regimen was used in the recipients.

Methods: Symptomatic patients were treated by deep sedation (ketamine, midazolam, and phenobarbital), ribavirin, interferon, and active and passive vaccination.

Genomic features and evolutionary constraints in Saffold-like cardioviruses.

This study identified the complete genomic sequence of four type 2 and type 3 human Saffold-like cardioviruses (SLCVs) isolated in Germany and Brazil. The secondary structures of the SLCV internal ribosome entry sites (IRESs) were deduced based on RNA base-pairing conservation and co-variation, using an established Theiler's murine encephalomyelitis virus (TMEV) IRES structure as a reference. The SLCV IRES was highly similar to that of TMEV, but motifs critical in TMEV for binding of the polypyrimidine tract-binding protein (PTB) were disrupted.

Detection of influenza A(H1N1)v virus by real-time RT-PCR.

Influenza A(H1N1)v virus was first identified in April 2009. A novel real-time RT-PCR for influenza A(H1N1)v virus was set up ad hoc and validated following industry-standard criteria. The lower limit of detection of the assay was 384 copies of viral RNA per ml of viral transport medium (95% confidence interval: 273-876 RNA copies/ml).

Incidence and risk factors for community-acquired acute gastroenteritis in north-west Germany in 2004.

In developed countries, acute gastroenteritis (AGE) is a major source of morbidity. However, only a few studies have estimated its incidence and the associated medical burden. This population-based study determined the incidence of community-acquired AGE patients seeking medical care and the relative role of various pathogens.

Circulation of 3 lineages of a novel Saffold cardiovirus in humans.

Cardioviruses cause serious disease, mainly in rodents, including diabetes, myocarditis, encephalomyelitis, and multiple sclerosis-like disseminated encephalomyelitis. Recently, a human virus isolate obtained 25 years ago, termed Saffold virus, was sequenced and classified as a cardiovirus. We conducted systematic molecular screening for Saffold-like viruses in 844 fecal samples from patients with gastroenteritis from Germany and Brazil, across all age groups.

Identification of a contemporary human parechovirus type 1 by VIDISCA and characterisation of its full genome.

Background: Enteritis is caused by a spectrum of viruses that is most likely not fully characterised. When testing stool samples by cell culture, virus isolates are sometimes obtained which cannot be typed by current methods. In this study we used VIDISCA, a virus identification method which has not yet been widely applied, on such an untyped virus isolate.

Effects of transgenic corn and Cry1Ab protein on the nematode, Caenorhabditis elegans.

The effects of the insecticidal Cry1Ab protein from Bacillus thuringiensis (Bt) on the nematode, Caenorhabditis elegans, were studied with soil from experimental fields cultivated with transgenic Bt corn (MON810) and with trypsinized Cry1Ab protein expressed in Escherichia coli. The content of Cry1Ab protein was above the detection limit of an ELISA test in only half of the soil samples obtained from transgenic plots, ranging from 0.19 to 1.

Prevalence, types, and RNA concentrations of human parechoviruses, including a sixth parechovirus type, in stool samples from patients with acute enteritis.

Parechovirus epidemiology and disease association are not fully understood. Real-time reverse transcriptase PCR (RT-PCR) for all human parechoviruses (HPeV) was applied on stool samples from two groups of patients. Both groups contained patients with acute enteritis of all age groups, seen during one full year.

Bacterial diversity of soils assessed by DGGE, T-RFLP and SSCP fingerprints of PCR-amplified 16S rRNA gene fragments: do the different methods provide similar results?

Bacterial communities of four arable soils--pelosol, gley, para brown soil, and podsol brown soil--were analysed by fingerprinting of 16S rRNA gene fragments amplified from total DNA of four replicate samples for each soil type. Fingerprints were generated in parallel by denaturing gradient gel electrophoresis (DGGE), terminal restriction fragment length polymorphism (T-RFLP), and single strand conformation polymorphism (SSCP) to test whether these commonly applied techniques are interchangeable. PCR amplicons could be separated with all three methods resulting in complex ribotype patterns.

[Frozen berries as a risk factor for outbreaks of norovirus gastroenteritis. Results of an outbreak investigation in the summer of 2005 in Hamburg].

An outbreak of acute gastroenteritis occurred in Hamburg among guests of a canteen in August 2005. A total of 241 persons were found ill. In stool samples of 16 of them Norovirus Genogroup I was identified.

Generic detection of coronaviruses and differentiation at the prototype strain level by reverse transcription-PCR and nonfluorescent low-density microarray.

A nonfluorescent low-cost, low-density oligonucleotide array was designed for detecting the whole coronavirus genus after reverse transcription (RT)-PCR. The limit of detection was 15.7 copies/reaction.

Field studies on the environmental fate of the Cry1Ab Bt-toxin produced by transgenic maize (MON810) and its effect on bacterial communities in the maize rhizosphere.

Field studies were done to assess how much of the transgenic, insecticidal protein, Cry1Ab, encoded by a truncated cry1Ab gene from Bacillus thuringiensis (Bt), was released from Bt-maize MON810 into soil and whether bacterial communities inhabiting the rhizosphere of MON810 maize were different from those of the rhizosphere of nontransgenic maize cultivars. Bacterial community structure was investigated by SSCP (single-strand conformation polymorphism) of PCR-amplified 16S rRNA genes from community DNA. Using an improved extraction and detection protocol based on a commercially available ELISA, it was possible to detect Cry1Ab protein extracted from soils to a threshold concentration of 0.

Re-examining the 16S rDNA sequence of Halomonas salina.

Previous reports of 16S rDNA sequencing of members of the family Halomonadaceae Franzmann et al. 1989 include two different sequences that were both attributed to the type strain of Halomonas salina (Valderrama et al. 1991) Dobson and Franzmann 1996 (basonym Deleya salina Valderrama et al.