By Athanasios Tsakris, professor of Microbiology at the School of Medicine of the Greek Academy of Sciences

One of the first studies to link global warming and environmental destruction to human health was by an Australian epidemiologist, Anthony McMichael, who in a 2003 study assessing the effects of flooding, malnutrition, polluted water and of malaria, estimated that 5.5 million DALYs—years lost to disease, disability, or premature death—were the cost of climate change in 2000 alone. and affecting more and more countries – including ours – the awareness and reflexes of governments and citizens (and the scientific community to some extent) to their public health consequences are not what one would expect based on the severity of the problem.

The World Health Organization has warned that climate change (already responsible, as an aggravating factor, for almost 1.5 million premature deaths annually in Europe) could be the most serious threat to health in the 21st century, leading to an increase in morbidity and mortality. By the end of this century, unless there is a drastic reduction in greenhouse gas emissions, 70% of Europeans could be exposed to weather-related disasters each year. The corresponding percentage of the period 1981-2010 was only 5%.

The puzzle has many pieces. The increasingly frequent heat waves burden those suffering from cardiovascular and respiratory diseases and cause deaths. Polluted atmosphere is also responsible for fatal diseases. Due to rising temperatures and the expansion of mosquito habitats, we are seeing the spread of dangerous tropical diseases in areas that have not experienced this threat until now. Plants produce more pollen for a longer period of time and trigger allergies and asthma. Heavy rainfall enhances the growth of bacterial and fungal pathogens on plants – some of which also infect humans. Next to these let’s think about the losses from extreme phenomena, drought, the reduction of drinking water supplies, the transmission of diseases through unclean water and contaminated food, the decline of productivity in rural areas, the shrinking of biodiversity.

All this requires the preparation of the health systems of the European countries and the development of strategies and mechanisms, so that they can respond to the new needs and threats. Heat waves, cyclones and abnormal rainfall, catastrophic floods, rising sea levels and infectious disease outbreaks will not be the exception for the foreseeable future – but, it seems, the new normal.

Decoding the complex interdependencies between climate change and our health – and the action that this entails – is one of the great challenges we must face as scientists and as societies in the coming years.