Peruvian sea lions die from bird flu – worrying signs are rising

Bird flu is currently raging in large parts of the world and is decimating bird populations, including in Peru. More than 55,000 dead birds have been found in protected areas in the South American country, including pelicans, penguins and gannets.

While it is known that avian flu, as the virus is also known, can wreak havoc on bird populations, there is another fact that is currently giving experts a headache: in addition to the thousands of birds found in Peru up to February 15, 634 dead sea lions on the coast.

A team of Peruvian and Argentinian researchers has now confirmed that the massive deaths of the animals are also due to bird flu, the Spanish newspaper “El País” reports. Sea lions are mammals and thus do not belong to the actual “target group” targeted by the bird flu virus.

It is precisely this fact that worries the scientists. In itself, the fact that mammals can contract bird flu is nothing new. In the past, infections in wild animals such as bears, foxes or martens have been reported. The difference, however, is that they contracted an infection from eating infected birds or coming into contact with their faeces.

The current case of Peruvian seals is different. Large groups of dead animals were sometimes found, their carcasses floating together in the water. Argentine biologist Sergio Lambertucci therefore questions the fact that all these animals were individually infected: “It wouldn’t be strange if some of them ate infected birds, but all of them?” he asks rhetorically in an interview with “El País”. . Thijs Kuiken, a Dutch expert on emerging animal diseases, also considers it likely that direct transmission between the sea lions took place.

In recent weeks there have been more and more reports that more and more mammals are affected by a virus infection. In particular, the case of a Spanish mink farm caused a stir – it was then that the suspicion arose for the first time that the avian flu virus could have evolved. However, the difference with the current case of seals in Peru is that the infections occurred in the wild – where the transmission conditions for a virus are significantly less favorable than with factory-bred minks.

Barbara Wieland, director of the Swiss Institute of Immunology and Virology, recently told SRF that the risk of bird flu infection for humans is low. The World Health Organization (WHO) also stated in a risk assessment in January that the virus is fundamentally incapable of being permanently transmitted between people.

However, if it turns out that the pathogen has actually evolved and that infections of South American sea lions have passed from one living animal to another, that would be concerning. Expert Kuiken told El País: “This is the second episode of mass mortality, suggesting that the virus has adapted to efficient mammal-to-mammal transmission. If it can happen to minks and sea lions, why couldn’t it happen to humans?”

In Peru, authorities are currently trying to keep people away from the dead animals to prevent the potential new strain of the virus from settling in human bodies. However, several scientists criticize the authorities’ response as too hesitant, fearing that people will come into contact with the virus sooner or later.

Biologist Lambertucci says: “Because of the worrying situation, we wanted to raise the alarm as soon as possible. It is the first case of mass extinction in wild mammals in South America and may be the first event of intraspecific transmission in wild mammals worldwide.” The researchers now want to test the hypothesis of direct animal-to-animal transmission using genetic testing.