Dead seabirds…yet another pandemic red flag

0

It was during a beach cleanup last week that we noticed them – first a dead guillemot, washed up on the sand, then another dead bird, further down a beach, and yet another, so run down that it was difficult for us to say what it was. I then wondered if it was avian flu, if this disease had already had a catastrophic impact on the seabird population of Shetland. Now here, killing the birds in the Firth of Forth?

But we did not report them to the DEFRA hotline, as I now realize we should have. Instead, we just stared at the bodies with sadness. Then news emerged that the epicenter of the outbreak had moved south and it seemed clear that those birds must have succumbed to the disease experts call highly pathogenic avian flu.

This current epidemic is primarily caused by a new, particularly deadly and pathogenic variant of the H5N1 avian influenza virus – and widely recognized as having originated in intensive animal husbandry in East Asia before being transmitted to wild birds. The result is, as Dr Peter Walton, species and habitats manager for RSPB Scotland, put it, a “new and unprecedented” impact on bird populations.

More than 383,000 bird deaths from the virus have been counted by the World Organization for Animal Health (WOAH) since October last year. This may seem relatively small, given that we are now accustomed to talking about global deaths of over 6 million humans from Covid, but it is devastating.

READ MORE: The Isle of May, home to 90,000 puffins – for how much longer?

Large numbers of barnacle geese have been killed by the virus in the Solway, with an estimated loss of around a third of Svalbard’s population. Some experts believe that 10% of UK gannets may have been killed by the disease. When a disease has this kind of impact, it can be difficult for the population to recover, especially when gannets live for 17 years and only lay one egg per year.

These seabirds, of course, are not only threatened by bird flu, but also by climate change and their changing food source, fishing and other human disturbances.

These wet carcasses washed up on our beaches are not only sad, they speak of a world that we have cultivated. Avian influenza may not be man-made, but as a recent report by the Food and Agriculture Organization of the United Nations described, these outbreaks of highly pathogenic avian influenza are usually associated with “domestic poultry production”. When the viruses spread through wild bird populations again – as they have done on numerous occasions since the 2000s – the disease can be carried across the continent by bird migrations.

Attempts, of course, have been made to try and stop the spread of the disease in and through poultry farming in the UK. It was only in May that after five months of mandatory indoor housing of poultry, farms were allowed to raise them outside again. The UK has recorded 121 cases of bird flu on farms since October, including ten in Scotland. The poultry sector understandably fears that restrictions will be imposed again

So far, this bird flu virus has remained entirely based in bird populations and the risk to humans is thought to be very low – but not zero. With so many viruses circulating in birds around the world, there is good reason to be concerned that, through mutations and genetic exchange, this virus may at some point acquire the ability to jump to humans. then to be transmitted between humans.

China, for example, reported 20 human cases of H5N6 avian influenza this year (almost all of which were exposed to live poultry), but no confirmed cases of human-to-human transmission.

The coronavirus pandemic has raised awareness of how interactions between humans, wild animals and intensive agriculture can all be part of the story of how disease mutates, spreads and spreads. Covid has alerted us to the amount of infectious disease rooted in ecological change and food production. Studies have shown that the emergence of zoonoses is often “linked to agricultural intensification and environmental changes”.

One of the questions we need to ask ourselves is whether it is how, globally, we raise poultry that is part of the problem. Another is whether climate change is part of this story. Many experts say so. Climatic and environmental changes create movements and migrations, generating situations where species make new contacts and pathogens jump more easily to new susceptible hosts.

Increasingly, the UN and WHO are talking about a “one health” strategy – in which the health of humans, our farm animals, wildlife and the planet at large are considered as one. and connected. Such a joint approach is vital. We are all connected, and bird flu is just another reminder of how we create the conditions for disease, not just for animals, but for ourselves.

Share.

Comments are closed.