Avian Influenza in Germany: University of Bremen Virologist Assesses Its Significance for Wild and Domestic Birds

The topic of avian influenza is currently occupying science, agriculture, and the public. We therefore spoke with virologist Dr. Andreas Dotzauer from the University of Bremen about risks, protective measures, and current findings.

Here is his expert opinion:

Avian influenza is an infectious disease caused by viruses that normally occurs in wild waterfowl. The virus, which is related to human influenza A viruses, can, however, be easily transmitted through the excretions of infected animals to other bird species, such as chickens, turkeys, and geese, when the same water sources and feeding areas are used. The viruses that are constantly present in wild birds do not cause any symptoms, but — as is the case now — can mutate into a highly contagious, fatal animal disease, also referred to as avian plague, in various bird species. Such dangerous mutations can also occur in poultry farms infected with viruses that are actually harmless and can be transmitted back to wild birds from there.

Mandatory housing along migration routes

Since early September, outbreaks in poultry farms with a highly pathogenic H5N1 virus strain have been increasing rapidly. At the same time, countless migratory birds across the country have died from this highly contagious virus strain, which has triggered mass mortality particularly among cranes. Where and how the virus entered the crane population is unknown. The risk of further spread among wild birds and of introduction into poultry farms, especially along bird migration routes, is high. To contain the epidemic, several hundred thousand animals in commercial poultry farms have already been culled, and mandatory housing has been imposed in many federal states.

Risk to humans considered low

Through direct contact with infected birds, including already dead ones, or with virus-containing particles, these viruses can also be transmitted to humans and to mammals such as cows and pigs, and in rare cases can then cause fatal illness. While symptoms in birds are nonspecific (fatigue, ruffled feathers, lethargic behavior), humans usually develop mild, flu-like symptoms and more rarely conjunctivitis. Because this is a virus adapted to birds, the risk to humans is considered low. Although the flu vaccine protects only to a limited extent against the avian virus (H5N1), as it targets human influenza A viruses (H1N1 and H3N2), there is currently no cause for concern.

About the person: Prof. Dr. Andreas Dotzauer is a nationally known virologist and lecturer at the University of Bremen. The virology department was founded in 1990 and has been headed by him since 2014. The native Hessian’s research focuses on hepatitis viruses and the pathogenesis of viral infections.