Bird flu has killed more than a thousand sea lions in Argentina: they study what the contagion looks like

Single-haired sea lions living in a colony on Argentina’s Atlantic coast are affected by the highly pathogenic avian influenza virus (AP/Juan Macri)

this Avian Influenza More than 1,000 people have died sea ​​lion living in coastal areas Argentina.The first case of this species was discovered in early August fire nationthe infection was then picked up by animals further north, even in ports Quacken and mar del platainside Province of Buenos Aires.

Confirmed by the National Agricultural Food Health and Quality Service (Senasa) database That 1,091 sea lions died since the outbreak. Of this total, 12 two-haired sea lions. The rest are monohaired sea lions (which are different species).

“Since August we continue to see 300 dead mammals on the coast, mainly on the coast of Rio Negro,” he told reporters. database General Coordinator of Epidemiology senassa, Andrea Marcos.In addition, it was also found 2 elephant seals They’re also dying from the virus on the reservation. tombo pointin Chubut Province.

Since the outbreak of avian influenza in February, the National Ministry of Health track people People who have close contact with affected animals.They are currently registered 21 suspected cases, has been studied, but they were all discardedaccording to the latest Health Combination Epidemiological Bulletin.

In February last year, Argentina detected its first cases of avian influenza in wild birds and poultry. The epidemic was under control in July

Outbreaks of this pathogen began Wild birds last February. Then they expanded to poultry from different provinces. For the first time, Argentina has lost the “avian flu-free” category for poultry. But there was a recovery last August after outbreaks in places such as commercial farms were found to be under control.

The great unknown is today How the avian influenza virus spreads and affects so many sea lions. “We don’t know yet. In order to answer this question, experimental studies should be conducted.” Marcos replied.

In conversation databaseveterinarians and researchers Plaza Pablo in Conisette He commented that there are several hypotheses that could explain this situation. “this hypothesis More likely, the infection is By infected wild birds cohabiting with sea lions. This can also happen in Peru. However, it is necessary to assess whether the virus has adapted and is spreading among sea lions. This possibility has been demonstrated in other mammals.In fact Mutation discovered in Chile Viruses isolated from sea lions may indicate some degree of adaptation. This has also been observed in mink in Spain,” he said.

In other words, one possibility is Sea lions may become infected through contact with wild birds that are sick or may be asymptomatically infected with the virus. Another possibility is wolf-to-wolf transmission, but this has not yet been confirmed. “Another factor to consider is Environmental persistence of virusesDr. Plaza emphasized that under certain salinity and temperature conditions, the virus can remain infectious for several days.

Senasa prepares a report on known effects of avian influenza on humans sea ​​lion in every 5 provinces in Argentina affected.

It’s unclear how the avian flu virus infected so many sea lions. Scientists have several hypotheses (AP/Juan Macri)

In the province of Buenos Aires, sea lion colonies once existed in quacken harbor and In the port of Mar del Plata. They have historically appeared on tourist postcards in these areas.According to Senasa, these habitats are home to 4,000 sea lions and 7% died. That is, at least within Buenos Aires 280 wolves.

Further south, in province of rio negrooutbreaks were detected among sea lions in the towns of San Antonio Oeste, near the colony of Punta Villariño, and in Lobería de Lobería. punta bermeja. The latter is believed to be the largest fur seal colony in South America. It permanently consists of 4,000 people.The mortality rate for this group is approximately 2% (80 persons).

Positive cases of avian influenza have also been reported in wolf packs in Puerto Piramides, Puerto Madryn, Camarones, Ciudad Commodore Rivadavia, Radatili and Punta Tombo. Chubut Province.

The strain affecting sea lions belongs to a strain called clade, which has been spreading throughout Asia, Africa, Europe and the Middle East since late 2020 and into 2021. It arrived in South America last year (Senasa)

It was found that within the protected area tombo point At least three penguins, two emperor cormorants, one giant petrel, two fur seals and two elephant seals died. All the birds tested negative for avian influenza, but one wolf and two elephants were infected with the virus. Senasa experts clarified: “The number of dead animals in Chubut province is very small, less than 4, with the exception of Camarones, where 84 sea lion carcasses were found.”

exist Santa Claus Wolves from towns such as Punta Loyola, Caleta Olivia and Puerto de Seado are affected. A similar situation occurred in Chubut Province, with less than 10 dead individuals.

in the province fire nation, the positive case occurred in Rio Grande Beach, 10 kilometers from Isla Lobos. 28 sea lion carcasses were found. With the exception of the first outbreak in Tierra del Fuego, there were no poultry farms within 10 kilometers of where sea lions appeared.

“However, Wolves unlikely to come into contact with commercial birds And in no case has the virus been detected in wild birds. “Experts pointed out.

Bird flu kills farmed mink in Spain

The spread of the avian influenza virus in Argentina occurred against the backdrop of its spread to the Americas, Europe and Asia. During 2022-2023, the Americas region has been suffering from avian influenza epidemics associated with: Subtype A (H5N1).

Evolutionarily speaking, circulating strains belong to a group called Clade Its genetic changes are similar to groups spreading throughout Asia, Africa, Europe and the Middle East in late 2020 and 2021. At the end of the same year, the virus was also discovered in North America. It spreads with “alarming speed” and has a high mortality rate, as warned Pan American Health Organization.

In addition to birds, the virus can also spread to mammal, like a sea lion Peru, Chile and Argentina even spanish mink. 18,000 sea lions died in Chile and more than 5,000 died in Peru.The virus has also been found in Uruguay.

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