So you’re walking down the street, minding your own business, when a dead pigeon falls right out of the sky. Well, it’s not just the stuff of science fiction any more. Moscow residents have been crying fowl (forgive me) about a plague of zombie pigeons that’s descended upon the city. Their street birds are dying in droves, and disturbingly, the government and public health agencies appear to be at a bit of a loss in terms of what to do about the situation.
Testing of the remains indicates that the birds aren’t dying of parrot fever or bird flu, which is good news. Both of these conditions are dangerous and highly infectious. Bird flu in particular could be a huge problem if it made the leap into another species, and it could potentially reach into humans. If a strain of virulent bird flu managed to infect Moscow’s pigeons, it could spread rapidly across the city and into the rest of Russia, causing a major epidemic that would be hard to put in check.
What the birds do appear to have is severe salmonella infections, and the bacterial infection is making them behave very strangely. Anyone who’s spent time in a city with pigeons (which is pretty much every city on Earth) knows that the birds tend to be lively and engaged with their environment. They flutter when people walk by, go through garbage in search of food, and are agile when it comes to finding good perches and checking out the view.
Not so in Moscow, where the “pecking dead” are staggering around drunkenly, going in circles, stumbling and finding it difficult to fly in a straight line. The listless and indifferent birds aren’t even going after crumbs on the streets, and they’re tumbling when they try to fly through windows or up to high roosts. Clearly, the intestinal infection is weakening the birds and may be causing neurological problems for them.
Aggressive salmonella is bad news, because this bacteria doesn’t need to evolve to strike humans too: it’s already fully equipped. Residents are being advised to avoid contact with the birds, and those who do inadvertently handle dead pigeons (we can’t imagine the circumstances involved there) should definitely wash their hands thoroughly afterwards and again before preparing food (of course, washing hands before preparing food is good practice anyway). If the outbreak doesn’t stay limited to birds, Moscow’s hospitals could be loaded with frantic patients experiencing nausea, vomiting and diarrhea. The result could be a public health crisis as the city rushes to meet the needs of people with the infection.
Curiously, government officials and agencies appear to have conflicting opinions on what’s causing the infection and what to do about it. In addition to salmonella, Newcastle disease has been put forward as a potential culprit. This infection is also zoonotic, meaning it can spread to humans, and it can cause severe eye infections. Officials aren’t taking any firm action in terms of quarantining birds, trying to control the spread of disease, or taking other measures for veterinary health, while citizens are receiving mixed information about their safety.
Some officials are assuring Moscow residents that the birds won’t harm them, while others are advising them to stay away from clearly ill birds, which is some confusing and contradictory messaging. This isn’t the first time Moscow has experienced a bird die-off, so the city may view it as routine, but it definitely shouldn’t. Such events aren’t normal, and could be a sign of an underlying public health issue that needs to be resolved.
Photo credit: Frédéric BISSON.