A scenario that we absolutely must prevent
In the USA, dairy cows are infected with the H5N1 virus and in turn infect people. A concerning development, says Charité infectious disease specialist Sander. For if the pathogen mixes with other influenza viruses, it could trigger a new pandemic - and that needs to be prevented now.
First, wild animals infect cows. Then, cows infect people. And finally, people infect other people. A terrifying scenario for the next pandemic - this time not through Corona, but through the Avian Flu Virus H5N1. Particularly concerning is the fact that we have already reached step two: H5N1 is currently spreading in dairy herds in the USA, hundreds of animals are affected. High virus loads have been detected in the milk, and several farm workers have already fallen ill. Is a Bird Flu Pandemic imminent?
No, says Leif Erik Sander, infectious disease specialist at the Berlin Charité, at least not yet. "It's not about spreading unnecessary fear of an imminent pandemic right now." But the risk should not be underestimated. "With the spread of H5N1 among cattle, we now have a situation where all precautions that can be taken should be taken." One of the greatest concerns of experts is that the Avian Flu Virus will continue to adapt, for example through a merger with common influenza viruses, making it more easily transmissible from person to person. "A scenario we must absolutely prevent," warns Sander.
"A change in the virus that we have been observing in Asia for decades has led to its worldwide spread in a relatively short time," says Sander. And then various new animal species were infected, from cats to alpacas to sea lions - and now dairy cows in the USA. "This means that adaptations can happen relatively quickly."
A Peek into the Glass Ball
How quickly H5N1 can adapt to humans is, according to the infectious disease specialist, an uncertain matter. "Nobody knows." However, it is particularly critical if the H5N1 virus mixes with seasonal influenza viruses. For the few infection cases in humans in the USA still run mild, comparable to a common cold. "But if the virus continues to adapt, it could attach to the cells in our upper respiratory tract," says Sander. Then it could lead to person-to-person transmissions and potentially severe disease symptoms.
Therefore, the infectious disease specialist calls for the outbreak among dairy cows in the USA to be tackled decisively. The good news: The world is not as helpless as it was at the beginning of the Corona pandemic. "The world has been preparing for a possible pandemic by influenza viruses (which also includes the H5N1 virus - Editor's note) for a long time," says Sander. "There are already approved vaccines that can be rapidly adapted to a virus once it triggers a pandemic."
As the first country in the world, Finland has been vaccinating against Bird Flu since the beginning of the month - even though there have been no reported cases of infection in humans there. However, the country had already experienced several large Bird Flu outbreaks on poultry and mink farms. Last year, almost half a million minks had to be killed out of fear of the virus spreading.
"Germany could have acted faster"
Germany could have acted faster, says Sander, looking back at the events of the past few weeks. "We have the knowledge and the means to prevent such a development," he says. "But it requires a coordinated effort from all parties involved, from politics to agriculture to research." And above all, it requires a high level of vigilance and a readiness to react quickly. "We have seen how quickly the situation can escalate," warns Sander. "We must not wait until it's too late."
For Germany, Sander sees no urgency. "Currently, there is no reason to vaccinate people." So far, there has been no confirmed case of H5N1 in livestock in this country, only isolated infections in wild birds. And the expert considers the risk of the virus being brought to Germany via US imports to be low. "We import very few milk products or cattle from the US." Moreover, milk viruses are reliably inactivated through pasteurization. "And consuming raw milk was also not a good idea before the H5N1 outbreak." Raw milk can not only transmit avian flu, but also other dangerous pathogens.
For cattle, there is no licensed vaccine available according to Sander. "This is because cattle were not on the radar for flu viruses until now." Moreover, the development of an H5N1 vaccine for cattle is complex and must be carried out under increased safety precautions. "But the work is in progress." Experts and experts assume that vaccinations could play an important role in protecting non-infected herds preventively.
And if an outbreak occurs in German livestock, the infectious disease expert can reassure: "Germany would probably have it under control much faster than the US." Therefore, there are established protocols for containing outbreaks among cattle and these would be implemented consistently in case of emergency - a legacy of BSE.
Despite the ongoing H5N1 outbreak in dairy cows in the USA, Sander stresses the importance of preventing a potential Bird Flu Pandemic through vaccination. He highlights the advancements made in preparing for such pandemics, as evidenced by Finland's proactive vaccination against Bird Flu despite no human cases. Sander also suggests that Germany could have acted faster in response to the situation, emphasizing the need for a coordinated effort from all relevant parties to prevent such developments.
