The threat of future pandemics has been heightened by the emergence of new influenza viruses. In recent years, researchers from the Helmholtz Centre for Infection Research (HZI) and the Medical Center — University of Freiburg have made significant progress in understanding how these viruses interact with host cells.

Led by Professor Christian Sieben’s team at HZI, scientists have developed a novel method to study the initial contact between influenza viruses and host cells. This breakthrough allows researchers to investigate the complex process of viral entry in unprecedented detail.

The researchers immobilized individual viruses on microscopy glass surfaces and then seeded cells on top. This innovative “upside-down” experimental setup enables scientists to analyze the critical moment when viruses interact with cells but do not enter them, stabilizing the initial cell contact for further investigation.

Using high-resolution and super-resolution microscopy, the team demonstrated that contact between the virus and the cell surface triggers a cascade of cellular reactions. The accumulation of local receptors at the binding site, the recruitment of specific proteins, and the dynamic reorganization of the actin cytoskeleton are just some of the processes observed in this study.

What’s more remarkable is that researchers applied their method not only to an established influenza A model but also to a novel strain found in bats. The H18N11 virus, which targets MHC class II complexes rather than glycans on the cell surface, was shown to cluster specific MHCII molecules upon contact with the cell.

This groundbreaking research has significant implications for understanding alternative receptors used by new and emerging influenza viruses. The findings provide a critical basis for investigating potential pandemic pathogens in a more targeted manner, identifying new targets for antiviral therapies, and ultimately developing effective treatments against future pandemics.

The EU project COMBINE, launched in 2025 and coordinated by Professor Sieben’s team at HZI, aims to investigate the virus entry process of newly emerging viruses. This research has far-reaching implications for understanding and combating infectious diseases, making it a significant contribution to the global fight against pandemics.

“The world is witnessing a breakthrough in influenza management with the discovery that a single oral dose of baloxavir marboxil (baloxavir) can significantly reduce the transmission of influenza within households. This landmark study, published in The New England Journal of Medicine, sheds light on the first robust evidence that an antiviral treatment can curb the spread of influenza to close contacts.

Conducted by a team of international researchers including the LKS Faculty of Medicine at the University of Hong Kong (HKUMed), the CENTERSTONE trial enrolled 1,457 influenza-positive index patients and 2,681 household contacts across 15 countries from 2019 to 2024. The participants were randomly assigned to receive either baloxavir or a placebo within 48 hours of symptom onset.

The primary endpoint was laboratory-confirmed influenza transmission to household contacts by day 5. And the results are nothing short of remarkable.

‘These findings highlight baloxavir’s potential not only to treat influenza but also to reduce its spread within communities,’ said Professor Benjamin Cowling, co-author of the study and Helen and Francis Zimmern Professor in Population Health. ‘This dual effect could transform how we manage seasonal influenza and prepare for future pandemics.’

The study underscores the complementary role of antiviral drugs alongside vaccination, particularly in unvaccinated populations or during pandemics when vaccines may not be immediately available. The discovery opens doors to new possibilities in public health, where a single dose of baloxavir could become an essential tool in managing and containing outbreaks.

This groundbreaking research has far-reaching implications for the way we approach influenza management and pandemic preparedness. It’s a testament to human innovation and our unwavering commitment to protecting global health.”

Citizen science projects have been gaining popularity worldwide, allowing individuals to contribute to scientific research while promoting public awareness and engagement. Two such platforms, iNaturalist and eBird, encourage people to observe and document nature, but how accurate is the ecological data that they collect? A recent study published in Citizen Science: Theory and Practice offers a compelling answer.

Researchers from the University of California, Davis, conducted an analysis of data collected by participants on both platforms. They found that citizen science data from iNaturalist and eBird can reliably capture known seasonal patterns of bird migration in Northern California and Nevada. This demonstrates that even though the two platforms differ substantially in their data collection methods and user demographics, they can be combined to produce robust datasets.

The study began as a student capstone project in Laci Gerhart’s Wild Davis field course, which teaches students about urban ecology and California ecosystems. Cody Carroll, now an assistant professor at the University of San Francisco, took the course in 2020 while completing his doctorate in statistics at UC Davis. After Carroll graduated, the team regrouped and took the project a step further by combining the iNaturalist data with data from eBird.

The researchers compared data for 254 different bird species observed in Northern California and Nevada in 2019 and 2022. They found that the two platforms showed similar seasonal patterns for over 97% of bird species. To “ground truth” their findings, Gerhart and Carroll teamed up with Rob Furrow, an assistant professor of teaching in the Department of Wildlife, Fish and Conservation Biology.

The combined iNaturalist and eBird data recapitulated a variety of known bird seasonality patterns within the region. For example, California Scrub-Jays are present year-round, whereas Bufflehead ducks arrive in mid-fall and depart in early spring. Western Tanagers pass through in late spring when they journey south for winter, and again in late summer as they fly back northwards to breed.

This study shows that citizen science data can be trusted, despite differences between platforms and user demographics. The findings have significant implications for scientific research and conservation efforts. As Gerhart notes, “Contributors to multiple, smaller projects can help make real discoveries about bigger issues.”

The researchers made a point to publish their results in an open-access journal and created a dashboard that allows people to explore and visualize the seasonality patterns for all 254 bird species. This demonstrates a commitment to transparency and public engagement, essential principles of citizen science.

In conclusion, this study demonstrates the power of publicly generated data and the importance of combining multiple datasets to address broader scientific questions. It also highlights the potential of citizen science platforms like iNaturalist and eBird to inspire people to connect with nature while contributing to important biological research.