Publications by authors named "Walter Haas"

Using participatory, virologic, and wastewater surveillance systems, we estimated when and to what extent reported data of adult COVID-19 cases underestimated COVID-19 incidence in Germany. We also examined how case underestimation evolved over time. Our findings highlight how community-based surveillance systems can complement official notification systems for respiratory disease dynamics.

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BackgroundNon-pharmaceutical interventions (NPIs) during the COVID-19 pandemic affected respiratory syncytial virus (RSV) circulation worldwide.AimTo describe, for children aged < 5 years, the 2021 and 2022/23 RSV seasons in Germany.MethodsThrough data and 16,754 specimens from outpatient sentinel surveillance, we investigated RSV seasonality, circulating lineages, and affected children's age distributions in 2021 and 2022/23.

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BackgroundEvaluating tuberculosis (TB) notification completeness is important for monitoring TB surveillance systems, while estimating the TB disease burden is crucial for control strategies.AimWe conducted an inventory study to assess TB reporting completeness in Poland in 2018.MethodsUsing a double-pronged inventory approach, we compared notifications of culture-positive TB cases in the National TB Register to records of diagnostic laboratories.

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The Russian invasion of Ukraine in 2022 caused a large migration to other European countries, including Germany. This movement impacted the TB epidemiology, as Ukraine has a higher prevalence of TB and multidrug-resistant TB rates compared to Germany. Our descriptive analysis of TB surveillance data reveals important information to improve TB care in people displaced from Ukraine.

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Article Synopsis
  • * In the German LeTriWa study, researchers worked with public health departments to pinpoint exposure sources 1-14 days before symptoms appeared, assigning weights to days of exposure to quantify risk.
  • * Findings showed a median incubation period of 5 days and a mode of 6 days, reinforcing the established 2-10 day range used for tracking Legionnaires' disease cases.
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Lightning discharges between charged clouds and the Earth's surface are responsible for considerable damages and casualties. It is therefore important to develop better protection methods in addition to the traditional Franklin rod. Here we present the first demonstration that laser-induced filaments-formed in the sky by short and intense laser pulses-can guide lightning discharges over considerable distances.

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Objective: To investigate SARS-COV-2 viral clearance and viral load kinetics in the course of infection in children aged 1-6 years in comparison with adults.

Methods: Prospective cohort study of infected daycare children and staff and their close contacts in households from 11/2020 to 06/2021. Adult participants took upper respiratory tract specimen from themselves and/or their children, for PCR tests on SARS-CoV-2.

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Background: The symptoms of SARS-CoV‑2 infections in children are mostly mild; however, the symptoms are highly variable. There are only a few studies on non-hospitalized children. The clinical picture described in hospitalized children cannot be transferred to non-hospitalized children and the frequency of certain symptoms in children may thus be overestimated.

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Background: During the five waves of the SARS-CoV-2 pandemic so far, German early childhood education and care (ECEC) centres implemented various protective measures, such as wearing a face mask, fixed children-staff groups or regular ventilation. In addition, parents and ECEC staff were increasingly vaccinated throughout 2021. During the 4th wave, variant of concern (VOC) Delta-driven transmission indicators reached record values at the end of 2021.

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In Germany tuberculosis is a rare disease and usually well treatable. Worldwide it is one of the most common infectious diseases with approximately 10 million new cases every year. Even with low incidences in Germany, tuberculosis is an important differential diagnosis especially due to international developments and migration movements.

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In daycare centres, the close contact of children with other children and employees favours the transmission of infections. The majority of children <6 years attend daycare programmes in Germany, but the role of daycare centres in the SARS-CoV-2 pandemic is unclear. We investigated the transmission risk in daycare centres and the spread of SARS-CoV-2 to associated households.

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Article Synopsis
  • This study investigated barriers and delays in preventing childhood tuberculosis (TB) through contact tracing and treatment in Berlin between 2009 and 2016.
  • It analyzed data from 48 children diagnosed with TB, revealing that most were identified through tracing, but many did not receive preventative treatment due to already having a prevalent infection.
  • The key finding suggests that timely diagnosis of adult TB cases is crucial for preventing childhood TB, along with better management of exposed children.
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Background: Comprehensive pathogen genomic surveillance represents a powerful tool to complement and advance precision vaccinology. The emergence of the Alpha variant in December 2020 and the resulting efforts to track the spread of this and other severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern led to an expansion of genomic sequencing activities in Germany.

Methods: At Robert Koch Institute (RKI), the German National Institute of Public Health, we established the Integrated Molecular Surveillance for SARS-CoV-2 (IMS-SC2) network to perform SARS-CoV-2 genomic surveillance at the national scale, SARS-CoV-2-positive samples from laboratories distributed across Germany regularly undergo whole-genome sequencing at RKI.

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German national surveillance data analysis shows that hospitalisation odds associated with Omicron lineage BA.1 or BA.2 infections are up to 80% lower than with Delta infection, primarily in ≥ 35-year-olds.

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Based on our national outpatient sentinel surveillance, we have developed a novel approach to determine respiratory syncytial virus (RSV) epidemic seasons in Germany by using RSV positivity rate and its lower limit of 95% confidence interval. This method was evaluated retrospectively on nine RSV seasons, and it is also well-suited to describe off-season circulation of RSV in near real time as observed for seasons 2020/21 and 2021/22 during the COVID-19 pandemic. Prospective application is of crucial importance to enable timely actions for health service delivery and prevention.

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As of December 31, 2019, initial reports circulated internationally of an unusual cluster of pneumonia of unknown cause in China. By the end of January 2020, the virus affected Germany with the first case confirmed on January 27, 2020. Intensive contact tracing and infection control measures contained the first two clusters in the country.

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Background: During the SARS-CoV-2 pandemic, German early childhood education and care (ECEC) centres organised children's attendance in different ways, they reduced opening hours, provided emergency support for a few children, or closed completely. Further, protection and hygiene measures like fixed children-staff groups, ventilation and surface disinfection were introduced in ECEC centres. To inform or modify public health measures in ECEC, we investigate the occurrence of SARS-CoV-2 infections among children and staff in ECEC centres in light of social determinants (i.

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Until today, the role of children in the transmission dynamics of SARS-CoV-2 and the development of the COVID-19 pandemic seems to be dynamic and is not finally resolved. The primary aim of this study is to investigate the transmission dynamics of SARS-CoV-2 in child day care centers and connected households as well as transmission-related indicators and clinical symptoms among children and adults. COALA ("Corona outbreak-related examinations in day care centers") is a day care center- and household-based study with a case-ascertained study design.

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Background: Enhancing tuberculosis (TB) prevention and care in a post-COVID-19-pandemic phase will be essential to ensure progress towards global TB elimination. In low-burden countries, asylum seekers constitute an important high-risk group. TB frequently arises post-immigration due to the reactivation of latent TB infection (LTBI).

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Background: Daycare centers are of substantial sociopolitical and pedagogical relevance; at the same time, the close contact of children in daycare groups among each other and with employees favors the transmission of infections. In the COVID-19 pandemic, questions arose about how infection events occur in daycare centers, what role daycare children play in the pandemic, and what protective and hygienic measures are implemented in daycare centers. From 06/2020 to 12/2021, we conducted the "Corona Day Care Study," in which we address pedagogical and infection epidemiological topics in a joint approach.

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The first case of coronavirus SARS-CoV‑2 infection in Germany was diagnosed on 27 January 2020. To describe the pandemic course in 2020, we regarded four epidemiologically different periods and used data on COVID-19 cases from the mandatory reporting system as well as hospitalized COVID-19 cases with severe acute respiratory infection from the syndromic hospital surveillance.Period 0 covers weeks 5 to 9 of 2020, where mainly sporadic cases of younger age were observed and few regional outbreaks emerged.

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