One hot summer day in ancient Sicily thousands of years ago, Noble Damocles is guest at a banquet of his tyrant king Dionysius. Surrounded by magnificence, power and authority Damocles envies the ruler and exclaims: ‘My king, you are truly extremely fortunate’. Promptly Dionysius offers to switch chairs with Damocles, so that Damocles can taste that very fortune. When Damocles accepts the proposal and sits down in the throne surrounded by every extravagance, Dionysius had arranged a huge, razor-sharp sword hanging above the throne, held only by a single hair of a horse’s tail.
Sounds like quite a health risk to take, doesn’t it? Let’s have a closer look….
We can define risks as undesirable consequences of actions, where two things matter: the extent of the damage and the probability of occurrence. In Damocles’ case the potential damage of the risk is the highest possible, namely the loss of his life, while the probability of occurrence is extremely low, for according to the myth the thread did not break.
Whereas the ‘Sword of Damocles’ has become a byword for a happy situation overshadowed by danger, risks to our health don’t always have to be as extreme. Of course there might always be meteorite on its way to –very improbably- wipe all the life from our green Earth. Yet, everyday life health risks are much more tangible. For instance, to increase the probability of one’s death by one in a million, one can choose to travel 6 minutes by canoe, eat 40 tablespoons of peanut butter, fly 1.000 miles by jet, smoke 1.4 cigarettes or live 2 days in New York’s polluted air.
Your peanut butter eating habit aside, the latter gives an indication where many health risks in our lives come from: the environment. Environmental hazards are responsible for an estimated 25% of the total burden of disease worldwide.
Pollution from Pandora’s box
And air pollution ‘is the single biggest environmental health risk’ with around 7 million deaths a year, according to a report the World Health Organization WHO issued last month. However, much worse affected than New York is Southeast Asia – now the most polluted region in the world with more than 5 million deaths from air pollution. Does this pollution stink from Pandora’s box, we have opened?
Pandora was the first woman on Earth, created by Zeus, the Greek ‘Father of Gods and Men’. One day men didn’t behave well and Zeus is furious with vengeance. Thus he gives Pandora a wedding gift of a beautiful jar, with instructions to not open it under any circumstance. But urged by her curiosity, Pandora can’t help but open it and all evil contained therein escapes and spread over the Earth.
As such evil, the health risk of air pollution can be seen: once freed, it can have persistent and ubiquitous consequences.
Climate Change Oracles
Thousands of years after their creation, people in Greece are often in doubt about important questions in their lives. On such hesitations the blind seeress Pythia can shed light. She is the most famous oracle and lives in the city of Delphi. One day, a weary king comes to the temple and asks the oracle if he would win the battle. She smiles and tells him a great king would win the battle. That was exactly what he had wanted to hear and he goes away happily. However, when he leads his men into battle, they lose and he is killed by the other king – the great king.
Pythia’s prophecies are enigmatic and ambiguous. They might reveal that a major danger is impending, but they won’t tell how high its probability, severity or distribution might be. The oracle is characteristic for many environmental health risks nowadays, which have high uncertainty with regard to both risk dimensions. Take climate change, already causing estimated 150,000 deaths annually. These occur, for instance, from more frequent extreme weather conditions, like Typhoon Haiyan, or from affected patterns of food production, impacting on malnutrition.
The same is true for biodiversity loss and the degradation of ecosystems: for many of the world’s poor, one of the greatest environmental threats to health remains lack of access to safe water and sanitation. Water resources, are replenished and purified by water ecosystems. When they are lost human health and well-being is undoubtedly put at risk, while exact probabilities, the severity or distribution remain yet unclear.
While sailing home from the Trojan War, the hero Odysseus and his men come ashore to restock their food and water. They are thrilled to find a cave full of sheep, build a fire in the cave, and cook some sheep on a sharpened stick. ‘Uaaagh’, suddenly echoes through the cave and a one-eyed giant appears at the mouth of the cave, swinging a club. Swiftly Odysseus grabs a sharpened stick and blinds the Cyclops, who is restricted by his one eye. Odysseus and his men get safely away by pretending to be sheep making bah-bah sounds until they crawled to safety.
The Cyclops’ limitation to perceive only one part of reality with his one eye describes also many health risks. When viewing them, only one side can be ascertained while the other remains unsure. It is often the case that risks are greatly underestimated whose magnitude can be grasped but whose probability of occurrence is uncertain or continuously changes.
Prominent examples are vector-borne diseases. Mankind has always co-habited with innumerable other living forms. While many of them support us, some few can transmit infectious diseases between humans or from animals to humans. Such ‘vectors’, are for instance mosquitoes, ticks, flies, or fleas. These benefit from tropical climate, inefficient water management, low priority for health impact in development activities, unplanned urbanization and widespread poverty, but also factors of a changing environment. Altering temperature and rainfall conditions as well as deforestation and loss of biodiversity, affect both the transmission and control of the most common vector-borne diseases including malaria, dengue and leishmaniasis. Especially in Southeast Asia malaria is still endemic in 10 of 11 countries, making up 40% of the global population at risk of malaria. With 17% of all infectious diseases, causing more than 1 million deaths annually, also the global magnitude of vector-borne diseases is clear. ‘Vector-borne diseases have significant impact on socioeconomic status of communities, and they vigorously fuel the vicious circle of poverty,’ says Dr. Poonam Khetrapal Singh, Regional Director of the WHO Southeast Asia, indicating the severe effects of such environmental health risks. Nevertheless, cyclops-like, we can’t fully grasp the probabilities of environmental impact. But there is no need to turn to stone.
How to Kill the Beast
Medusa is a beautiful, young woman with magnificent long, silky hair. One day, while she is in goddess Athena’s temple, she fools around with the god Poseidon which angers Athena. She is so mad she changes Medusa’s beautiful hair into hissing serpents and makes her into a horrible looking monster. Medusa is now so horrible that any living thing that looks upon her turns to stone.
In ancient Greece, the world was full of dangers. Some novel phenomena affect people today with the same fear and dread. Instead of turning into stone, however, there are solutions at hand. Remember, Medusa was defeated in the myth with a smart strategy, using a mirror, rather than looking directly in her eyes. Such strategies are emphasized by the WHO, which is reinforcing the linkages between health and environment. An example is ‘Integrated Vector Management’, promoting greatest disease control benefit, while minimizing negative impacts on ecosystems e.g. from the excessive use of chemicals.
Fittingly, this year’s World Health Day on April 7th is inviting to ‘protect yourself from vector-borne diseases’, aiming to create necessary behavioral change. To do so, the WHO works with partners to provide education and improve awareness so that people know how to protect themselves and their communities. But even more important are the conservation of a healthy environment and the mitigation of climate change to minimize the environmental health risks in the first place. On this focuses the ‘Health and Environment Linkages Initiative’ by the WHO and the UN Environment Program, as does the ASEAN Centre for Biodiversity in the region. The Philippine-based Centre, supported by the GIZ (Deutsche Gesellschaft für Internationale Zusammenarbeit) since 2010, coordinates sustainable use and conservation of biodiversity. After all, the best risk management is prevention: Healthy ecosystems for healthy people. Let’s take this wakeup call seriously and avoid Cassandras’ destiny:
Cassandra was a beautiful young priestess at Apollo’s temple, with great ambition. One day, the mighty god Apollo swings by and is delighted by Cassandra. He is fond of making a deal. If Cassandra kisses him, he would give her the gift of prophecy so she could see into the future. Cassandra does not hesitate. As soon as she is able, she looks eagerly into the future. But she does not like what she sees: Apollo is helping to destroy her beloved city of Troy. She spits in his face. Apollo is furious, and since he could not take away his gift, he adds to it. From that time on, Cassandra could see the future, but no one believed a thing she said. Later, when Cassandra warned her people that the Trojan horse was a trap, nobody paid the slightest attention. They laughed at her and widely opened the doors…