JR・ボーンさんのインスタグラム写真 - (JR・ボーンInstagram)「Another informative post by @seed “...rethink our relationship with all other living things and be mindful of our own spillover on the planet.” #Repost @seed ・・・ According to the NIH, zoonotic diseases (illnesses that pass from animals to humans) account for roughly 60% of known infectious diseases, and those carried by bats—including rabies, Ebola, and the latest SARS-CoV-2—have some of the highest fatality rates. Yet bats themselves rarely experience symptoms of these diseases. But why?⁠ ⁠ Bats are one of the oldest mammals and the only to have developed powered flight. Flight isn’t an easy adaptation. To “break away” from other land mammals, bats had to develop not only wings, but also a supercharged metabolism. In any other mammal, especially such a small one, an elevated metabolic rate = shorter lifespan.⁠ ⁠ Yet in bats, the opposite is true. Bats can live up to 40 years, while other mammals their size might live fewer than 5. A recent study¹ found that the adaptation that enables flight in bats also appears to reduce stress, repair DNA damage, manage inflammation, and tolerate uniquely destructive viruses. These immune defenses also “block” viruses from entering bat cells without actually killing the virus, meaning the virus is able to linger and replicate at a rate not seen in other species.⁠ ⁠ But are bats to blame? Or are we?⁠ ⁠ When viruses like SARS-Cov-2 spillover from animals to humans, it’s almost always because humans have stressed or intruded on another species and its environment, through destructive practices like the illegal wildlife trade, deforestation, climate change, and urbanization.⁠ ⁠ COVID-19 is not just a pandemic, it’s a warning from nature. An urgent reminder of our place in a larger ecosystem. And a call for us to rethink our relationship with all other living things and be mindful of our own spillover on the planet. Until we do, another global outbreak is a matter of when, not if.⁠ ⁠ _____⁠ ⁠ ¹ Brook et al, “Accelerated viral dynamics in bat cell lines, with implications for zoonotic emergence.” University of California, Berkeley. eLife 2020;9:e48401 DOI: 10.7554/eLife.48401」4月15日 4時49分