Of 375 infectious diseases, 218 experienced a worsening due to climatic hazards, underlines an American study published in the journal Nature Climate Change this August 8, 2022. The latter points the finger at the link between climate change and the impact of allergic or infectious diseases in humans: 58% of them would have become more dangerous. Among them, 160 were aggravated by warming alone, 81 by droughts or 21 by fires.
The impact of diseases such as Lyme, dengue, or even malaria has been analyzed by measuring climatic hazards due to the emission of greenhouse gases, resulting in droughts, fires, floods, heat waves or storms. The researchers came to the conclusion that environmental change and the worsening of infectious diseases were linked and that these meteorological events tended to amplify the impact of these pathologies.
More transmission vectors
On the one hand, with global warming, these diseases are transmitted by more vectors, they note, on the other hand, greater diversity of pathogen types now affecting humans (viruses, bacteria, fungi, animals…). The authors thus identified more than 1,000 transmission routes, “such as mosquitoes, ticks or fleas“, indicates Yannick Simonin, virologist at Inserm, at World. With warming, certain diseases can also be transmitted by water, such as gastroenteritis or certain meningoencephalitis.
If the 58% figure is an estimate, the researchers claimed that conversely, 16% of these diseases have been mitigated with climate change that we have known in recent years. “The rate of 58% must be put into perspective, but it has the merit of giving an order of magnitude and alerting to the importance of climate change in the increase in human diseases linked to pathogens, whether these diseases are emerging or more old“, concludes the virologist.
Sources:
- Over half of known human pathogenic diseases can be aggravated by climate change, Nature Climate ChangeAugust 8, 2022
- More than half of human infectious diseases would be aggravated by climate change, The worldAugust 8, 2022
