Hope injection: women with their pets at a rabies vaccination centre in India. Photo: Noah Seelam/AFP/Getty Images
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Preventing rabies: the dog jabs that can save humans

Responsibility for treatment of infected people falls on human health services. It is difficult to create an alliance against rabies until animal and human health experts co-ordinate.

By the time you read this, more than 3,000 people will have died in the current Ebola outbreak in West Africa. Barack Obama has said that the world is not doing enough to counter the disease. This may be true but there are other diseases more worthy of an international collaborative effort.

Ebola has a strange power over us. Its rapid spread and dramatic symptoms (bleeding from the eyes, for instance) and high kill rate evoke a panic response. But as Seth Berkley, who leads the Global Alliance for Vaccination and Immunisation (Gavi), has said, we should probably be more concerned about the resurgence of measles, the persistent killing power of dengue shock syndrome and the creeping number of cases of rubella and pertussis, also known as whooping cough. And then there’s rabies. The disease has an almost 100 per cent fatality rate, accounting for 69,000 deaths a year. It kills 75 children each day. The progression of the disease is, like Ebola, a slow agony that ends with multiple organ failure. But unlike Ebola, this disease is entirely preventable – and has been since 1885, when the first vaccine was developed.

In the 26 September issue of the journal Science, a group of researchers called for mass dog vaccination to counter the threat. Their pilot programme in Tanzania achieved 70 per cent immunity in the dog population by administering a rabies vaccine. This was enough to reduce the human rabies infection rate in the region from 50 per year to almost zero.

The main reason the rabies threat hasn’t been tackled is what the researchers term the “responsibility gap”. As they point out, the only infectious diseases we have ever eradicated are smallpox and rinderpest. One is an exclusively human infection; the other exclusively animal. Dogs, which are the main reservoir for the rabies virus, are the province of veterinarians. Responsibility for treatment of infected people (95 per cent of whom are in Africa and Asia) falls on human health services. It is difficult to create an alliance against rabies until animal and human health experts co-ordinate to pool funding.

It wouldn’t take vast resources. A dog vaccination programme would cost significantly less than is spent on treating people who have been exposed to the virus (the saving would be particularly valuable in Asia, where 90 per cent of such treatments take place). Initially, vaccination requires about $200 per square kilometre, the researchers estimate. Once the local pooches are rabies-free, the cost of maintaining the required 70 per cent immunity is about half that.

And don’t be sidelined by the myth that roaming packs of strays are a problem. Studies show that less than 11 per cent of dogs in African countries are ownerless and the trial programmes have successfully vaccinated what the researchers coyly term “community dogs”.

Not that rabies is an exclusively canine issue. The most recent death in the UK, which occurred in 2002, came from a bat bite. That’s also true of the US: in 2011, a woman in South Carolina died of rabies after being bitten by a bat that had flown into her bedroom. Yet bats are not big reservoirs for the virus. In the UK, the infection rate is about ten per 12,000. The last time a British bat was found to be carrying rabies was in 2008.

This low level of bat-borne infection may be because we have been so successful with our canine immunisation programmes. Research in Africa suggests that other animal species in the locality become rabies-free once local dogs are immunised.

What is needed now is a coalition committed to make that happen. Ebola can wait.

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At the Edge of Uncertainty: 11 Discoveries Taking Science by Surprise.

This article first appeared in the 30 September 2014 issue of the New Statesman, ISIS vs The World

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Not just a one-quack mind: ducks are capable of abstract thought

Newborn ducklings can differentiate between objects that are the same and objects that are different, causing scientists to rethink the place of abstract thinking.

There’s a particular loftiness to abstract thought. British philosopher and leading Enlightenment thinker John Locke asserted that “brutes abstract not” – by which he meant anything which doesn’t fall under the supreme-all-mighty-greater-than-everything category of Homo sapiens was most probably unequipped to deal with the headiness and complexities of abstract thinking.

Intelligence parameters tail-ended by “bird-brained” or “Einstein” tend to place the ability to think in abstract ways at the Einstein end of the spectrum. However, in light of some recent research coming out of the University of Oxford, it seems that the cognitive abilities of our feathery counterparts have been underestimated.

In a study published in Science, led by Alex Kacelnik – a professor of behavioural psychology – a group of ducklings demonstrated the ability to think abstractly within hours of being hatched, distinguishing the concepts of “same” and “different” with success.

Young ducklings generally become accustomed to their mother’s features via a process called imprinting – a learning mechanism that helps them identify the individual traits of their mothers. Kacelnik said: “Adult female ducks look very similar to each other, so recognising one’s mother is very difficult. Ducklings see their mothers from different angles, distances, light conditions, etc, so their brains use every possible source of information to avoid errors, and abstracting some properties helps in this job.”

It’s this hypothesised abstracting of some properties that led Kacelnik to believe that there must be more going on with the ducklings beyond their imprinting of sensory inputs such as shapes, colours or sounds.

The ability to differentiate the same from the different has previously been used as means to reveal the brain’s capacity to deal with abstract properties, and has been shown in other birds and mammals, such as parrots, pigeons, bees and monkeys. For the most part, these animals were trained, given guidance on how to determine sameness and differences between objects.

What makes Kacelnik’s ducklings special then, as the research showed, was that they were given no training at all in learning the relations between objects which are the same and object which are different.

“Other animals can be trained to respond to abstract relations such as same or different, but not after a single exposure and without reinforcement,” said Kacelnik.

Along with his fellow researcher Antone Martinho III, Kacelnik hatched and domesticated mallard ducklings and then threw them straight into an experiment. The ducklings were presented pairs of objects – either identical or different in shape or colour – to see whether they could find links and relations between the pairs.

The initial pairs they were presented served as the imprinting ones; it would be the characteristics of these pairs which the ducklings would first learn. The initial pairs involved red cones and red cylinders which the ducklings were left to observe and assimilate into their minds for 25 minutes. They were then exposed to a range of different pairs of objects: red pyramid and red pyramid, red cylinder and red cube.

What Kacelnik and his research partner found was that the ducklings weren’t imprinting the individual features of the objects but the relations between them; it’s why of the 76 ducklings that were experimented with, 68 per cent tended to move towards the new pairs which were identical to the very first pairs they were exposed to.

Put simply, if they initially imprinted an identical pair of objects, they were more likely to favour a second pair of identical objects, but if they initially imprinted a pair of objects that were different, they would favour a second pair of differing objects similar to the first.

The results from the experiment seem to highlight a misunderstanding of the advanced nature of this type of conceptual thought process. As science journalist Ed Yong suggests, there could be, “different levels of abstract concepts, from simple ones that young birds can quickly learn after limited experience, to complex ones that adult birds can cope with”.

Though the research doesn’t in any way assume or point towards intelligence in ducklings to rival that of humans, it seems that the growth in scientific literature on the topic continues to refute the notions that human being as somehow superior. Kacelnik told me: “The last few decades of comparative cognition research have destroyed many claims about human uniqueness and this trend is likely to continue.”